Abstract
Artificial Intelligence (AI) systems, particularly generative models, have demonstrated remarkable capabilities but are frequently beset by the phenomenon of “hallucinations”—outputs that are false, misleading, or nonsensical, yet appear plausible and are presented as factual. This report provides a comprehensive examination of AI hallucinations, beginning with a systems-level overview of their emergence from limitations in model training data, architectural design, and inference mechanisms. It delineates the broad landscape, defining AI hallucinations and their varied manifestations across Large Language Models (LLMs) and multimodal systems, including text-to-image and text-to-video generation. The core technical drivers, encompassing data quality issues, model overfitting, and deficiencies in grounding and common-sense reasoning, are analyzed. The report identifies high-risk domains such as healthcare, law, journalism, finance, and cybersecurity, where hallucinations pose significant threats. A deep dive into the real-world consequences and ethical risks of these phenomena reveals tangible negative impacts through detailed case studies. This focused section analyzes the profound ethical implications arising from the deployment of generative AI in high-stakes environments, discussing risks to trust, the amplification of misinformation, perpetuation of bias, and broader social harm. The critical importance of understanding and addressing AI hallucinations is emphasized as essential for fostering trustworthy AI. The report concludes by arguing for proactive intervention, including robust mitigation strategies, responsible development practices, and appropriate governance, to shape a future where human-AI collaboration can flourish responsibly, public trust is maintained, and innovation serves societal well-being.
1. Introduction: When AI Lies—But Sounds Like It Knows What It’s Talking About
The rise of generative AI has sparked awe and optimism. [cite: 3] Tools like ChatGPT, DALL-E, and Midjourney can produce fluent text, stunning visuals, and even code in seconds. [cite: 3] But beneath the surface lies a dangerous flaw: these systems often ” AI hallucinate”—producing information that is false, misleading, or entirely made up, but delivered with eerie confidence. [cite: 4] In sectors like healthcare, law, and finance, these AI hallucinations are more than quirks—they’re risks with real-world consequences. [cite: 5] This article unpacks what AI hallucinations are, how they arise, where the dangers lie, and why solving this problem is key to building trustworthy AI. [cite: 6]
🎥 Watch: Understanding AI Hallucinations
What Is an AI Hallucination? [cite: 7]
An AI hallucination occurs when an artificial intelligence system generates content that is plausible-sounding but false. [cite: 7] Unlike human errors, AI hallucinations are not simply slip-ups. They’re the result of how generative AI models work: by predicting patterns based on data—not verifying facts or understanding meaning. [cite: 8] Examples include: [cite: 9]
A chatbot citing fake scientific studies. [cite: 9]
A legal AI fabricating court cases. [cite: 9]
An image generator producing six-fingered humans. [cite: 9]
These aren’t rare glitches—they’re systematic flaws. [cite: 10]
Why Hallucinations Happen [cite: 10]
Data Problems : AI models learn from internet-scale data, which often includes noise, bias, and outdated or incorrect information. [cite: 11]
Architecture Limitations : Models optimize for fluency and coherence—not truth. [cite: 11] The more creative or open-ended the task, the higher the risk. [cite: 12]
Inference Mechanics : Generative models use probabilistic guessing. [cite: 13] When they lack information, they “fill in the gaps” with what seems likely, not necessarily what’s true. [cite: 13]
Lack of Grounding : Most models have no access to real-time or verified knowledge unless explicitly built in (e.g. via retrieval-augmented generation). [cite: 14]
The Real-World Fallout: Where Hallucinations Cause Harm [cite: 15]
- Healthcare [cite: 16]
An AI chatbot named “Tessa” was taken offline after it offered harmful advice to users with eating disorders. [cite: 16] Inaccurate AI-generated medical information—such as incorrect dosages or false diagnoses—can be life-threatening. [cite: 17]
- Law [cite: 18]
Several lawyers have faced penalties for submitting court filings based on AI-generated legal citations that simply didn’t exist. [cite: 18] In legal systems built on precedent, this undermines justice and professional accountability. [cite: 19]
- Finance [cite: 20]
When Google’s Bard chatbot made a factual error in a public demo, Alphabet lost $100 billion in market value. [cite: 20] Hallucinations in financial advice or customer service bots can trigger lawsuits and reputational damage. [cite: 21]
- Journalism and Media [cite: 22]
AI can generate fake news or deepfakes that look and sound real. [cite: 22] During the 2024 New Hampshire primary, AI-generated robocalls mimicked President Biden’s voice, misleading voters. Such hallucinations threaten democratic trust. [cite: 23]
- Cybersecurity [cite: 24]
AI tools used in security can hallucinate threats or miss real ones—either way, the impact can be catastrophic. [cite: 24] In code generation, hallucinated vulnerabilities can be unknowingly deployed in production systems. [cite: 25]
Ethical Risks and Public Trust [cite: 26]
AI hallucinations don’t just cause technical errors—they pose ethical risks: [cite: 26]
Bias Amplification : AI Hallucinations can perpetuate stereotypes or misrepresent marginalized groups. [cite: 26]
Disinformation : AI can be weaponized to produce false but convincing content at scale. [cite: 27]
Accountability Gaps : When things go wrong, it’s often unclear who’s responsible—developers, deployers, or users. [cite: 28]
Erosion of Trust : Once public trust is lost, it’s hard to regain. [cite: 29] One high-profile hallucination can cast doubt on legitimate applications. [cite: 29]
Can We Fix AI Hallucinations? [cite: 30]
There’s no silver bullet—but progress is being made. Approaches include: [cite: 30]
Better Data Curation : Cleaner, more representative training datasets. [cite: 31]
Human Feedback : Reinforcement Learning from Human Feedback (RLHF) to align outputs with truth. [cite: 32]
Retrieval-Augmented Generation (RAG) : Linking models to verified databases or live search. [cite: 33]
Fact-Checking Plugins : Integrating external validators into AI workflows. [cite: 30]
User Education : Teaching users to treat AI as a collaborator—not an oracle. [cite: 34]
However, each fix brings trade-offs. Increasing accuracy often means more computation, slower response times, or loss of creativity. [cite: 35]
What’s Next: Designing for Responsible AI [cite: 39]
To make AI genuinely useful and safe, we must design for responsibility: [cite: 39]
Transparency : Systems should signal uncertainty or cite sources. [cite: 36]
Governance : Clear legal frameworks for AI accountability. [cite: 39]
Human Oversight : Especially in high-stakes domains like health or law, humans must remain in the loop. [cite: 37]
Explainability : Users need to understand why the AI made a decision, not just the result. [cite: 38]
The future of AI depends not just on what it can generate—but whether we can trust it. [cite: 39]
Final Introduction Thought [cite: 40]
AI hallucinations are not bugs. They are features of the current generation of generative models. [cite: 40] As AI becomes more embedded in our lives, from customer service to clinical decision-making, these AI hallucinations must be addressed head-on. [cite: 41] Solving this challenge is not just about better code. It’s about aligning AI with human values, societal norms, and ethical principles. [cite: 42] That’s how we unlock AI’s potential—without losing trust in the process. [cite: 42]
1.1. Defining AI Hallucinations: Beyond Plausible Untruths
AI hallucinations are broadly understood as outputs generated by AI systems that are false, misleading, or nonsensical, yet are often presented with a veneer of plausibility that can make them appear factual.1 Microsoft Bing offers a definition wherein an AI, particularly a large language model (LLM), perceives patterns or objects that are non-existent or imperceptible to human observers, leading to the creation of nonsensical or inaccurate outputs.1 These errors are not merely random mistakes; they often stem from the fundamental way AI models, especially LLMs, operate—by using statistical patterns learned from vast datasets to predict sequences of text or other data, rather than engaging in true comprehension or reasoning about the information they process.4 Consequently, the generated content can appear coherent and linguistically fluent but may lack any reliable basis in reality or even in the model’s own training data.4
The term “hallucination,” borrowed from human psychology, is both illustrative and potentially problematic. It aptly captures the AI’s production of apparent non-realities. However, human hallucinations are complex perceptual experiences tied to consciousness and a subjective sense of reality, attributes that current AI systems do not possess. The analogy, therefore, while useful for conveying the “unreal” nature of the output to a broader audience, risks anthropomorphizing AI. This could obscure the underlying technical failures—such as flawed data processing, model miscalibration, or architectural limitations—and might lead to miscalibrated public expectations about AI’s “cognitive” abilities or its capacity for genuine understanding. Acknowledging the utility of the term while cautioning against its over-interpretation is crucial for a nuanced discussion.
A key characteristic of AI hallucinations is that the outputs “appear plausible”.1 This plausibility is a direct consequence of the models’ success in learning to generate human-like language and content. The very mechanisms that enable an LLM to produce fluent, coherent prose are the same ones that can lead it to construct elaborate, convincing falsehoods when not adequately constrained by factual grounding or when attempting to fill knowledge gaps. This deceptive plausibility makes hallucinations particularly insidious, as they can be difficult for users, especially non-experts, to detect without rigorous verification. The more sophisticated and human-like AI generation becomes, the greater the challenge in distinguishing veridical output from hallucinated content, thereby increasing the cognitive burden on users and heightening the need for built-in verification mechanisms or clear signaling of uncertainty by AI systems. The distinction from human imagination is also pertinent; AI models are not self-aware and cannot inherently distinguish between what is grounded in verifiable data and what is an “imagined” or confabulated extension based on learned patterns.7
1.2. A Systems-Level Overview: How Hallucinations Emerge in AI Models
AI hallucinations are not isolated bugs but rather systemic issues deeply rooted in the current paradigms of AI development and operation. They emerge from a complex interplay of factors that span the entire lifecycle of an AI model, from data collection and training to architectural design and inference-time generation.2 At their core, AI models, particularly deep learning systems, learn by identifying and internalizing patterns from the data they are trained on.2 If this training data is insufficient, biased, flawed, outdated, or poorly structured, the model may learn incorrect or incomplete patterns, which can subsequently manifest as hallucinations when the model generates outputs.2 The core objective for many generative models is often language fluency or visual coherence, which can be prioritized over strict factual accuracy, especially when faced with ambiguous inputs or topics for which training data is sparse.4 A critical contributing factor is the general lack of robust real-world grounding in many AI systems; models may excel at manipulating symbols and patterns but lack a deeper, causal understanding of the concepts these symbols represent.2
The widely cited “Garbage In, Garbage Out” (GIGO) principle, which posits that the quality of output is determined by the quality of input, is foundational to understanding one major source of AI errors. However, AI hallucinations reveal a more nuanced problem that can be described as “Garbage In, Plausible-Sounding Garbage Out,” or even “Adequate Data In, Peculiarly Specific or Contextually Inappropriate Garbage Out.” This suggests that AI hallucinations are not solely attributable to the quality of input data. They can also be emergent failure modes arising from the model’s learning process itself, its architectural choices, or the statistical nature of its generation mechanisms, even when the training data is not overtly “garbage.” For instance, a model might create novel, incorrect connections between concepts or fill knowledge gaps in a manner that is statistically plausible according to its learned patterns but factually erroneous or nonsensical in the real world. This implies that while meticulous data curation and cleaning are essential, they alone will not eradicate all forms of AI hallucination. Innovations in model architecture, the development of training objectives that go beyond mere sequence prediction to incorporate notions of truthfulness or verifiability, and robust inference-time checking mechanisms are equally critical.
Furthermore, the causes of AI hallucinations are often interconnected. For example, biases present in the training data 4 can lead a model to develop algorithmic biases 4, which then influence its inferences and outputs. A model with a poorly designed architecture 4 might be more susceptible to overfitting 4—memorizing specific patterns from the training data, including noise—which in turn makes it more likely to generate non-generalized, hallucinated content when presented with novel inputs. The inference mechanisms, which determine how the model generates an output based on what it has learned, act upon this learned representation, potentially amplifying existing flaws.4 This interconnectedness indicates that mitigating hallucinations effectively requires a holistic, multi-pronged strategy that addresses various stages of the AI lifecycle. A systems-thinking approach, considering the interactions between data, model, training, and deployment, is necessary rather than relying on isolated fixes to individual components.The Landscape of AI Hallucinations
Understanding the diverse ways AI hallucinations manifest and their underlying technical drivers is crucial for developing effective mitigation strategies and for appreciating their potential impact. This section explores these facets, providing a broad overview of the current landscape.
2. The Landscape of AI Hallucinations
2.1. Manifestations Across AI Modalities
AI hallucinations are not confined to a single type of AI model; they appear in various forms across different modalities, from text-generating Large Language Models (LLMs) to complex multimodal systems that process and generate images, video, and audio.
2.1.1. Hallucinations in Large Language Models (LLMs)
Large Language Models, renowned for their ability to generate human-like text, are particularly prone to a wide spectrum of hallucinations. These can range from subtle factual inaccuracies to elaborate, entirely fabricated narratives. Common manifestations include:
- Factually Incorrect Statements: LLMs may generate information that is demonstrably false, such as attributing incorrect dates to historical events, misstating scientific facts, or assigning false accomplishments to individuals.1 For instance, an LLM might incorrectly predict an event that is highly unlikely to occur or provide a summary of a news article that includes details not present in the original text, or even fabricates information entirely.2
- Nonsensical or Logically Incoherent Outputs: Models can produce text that, while grammatically correct, lacks logical coherence or makes no sense within the given context.1 This could involve generating irrelevant responses or answers that contradict common sense.
- Internal Inconsistencies: An LLM might contradict itself within a single response or across multiple turns in a conversation, indicating a lack of stable knowledge representation.1
- Fabricated Details and Sources: LLMs are known to invent specific details, such as names, statistics, awards, or entire events, that have no basis in reality.1 A particularly problematic form of this is the fabrication of citations or web page links that lead nowhere or to irrelevant content.2
- Emotional Manipulation: Some responses might be crafted to evoke strong emotional reactions, which, if not contextually appropriate, could be a sign of the model attempting to generate engaging content without a factual basis.1
- Lack of Verifiable Sources: When presenting factual claims, a reliable system should ideally provide or be ableable to point to its sources. LLMs that state “facts” without any attributable basis are often hallucinating.1
- Irrelevant or Overly Specific Trivia: The inclusion of out-of-place technical details or obscure, unverified trivia can also be an indicator of AI hallucination, where the model is filling space with statistically plausible but contextually inappropriate information.1
- False Positives/Negatives: In tasks that involve classification or prediction, LLMs can exhibit hallucinations in the form of false positives (e.g., flagging a legitimate financial transaction as fraudulent) or false negatives (e.g., failing to identify a cancerous tumor in a medical context, if the LLM is part of a diagnostic pipeline).2
The diverse range of these manifestations, from simple factual errors like incorrect dates to complex fabrications such as entirely non-existent legal precedents 9, suggests varying degrees of detachment from a grounded understanding. This spectrum may correlate with factors like the complexity of the user’s query, the ambiguity or sparsity of relevant training data, or the extent to which the model is forced to extrapolate beyond its learned knowledge. Simpler queries with ample, clear training data might result in minor errors, whereas complex, underspecified, or out-of-distribution queries could trigger more elaborate fabrications as the model attempts to “fill in” larger perceived gaps in information. This implies that the nature of the input prompt and the characteristics of the underlying data landscape relevant to that prompt are critical determinants of the type and severity of hallucinations. Consequently, robust uncertainty quantification—whereby a model indicates its level of confidence in an output—could be a key mitigation approach; the more a model has to invent or extrapolate, the less certain its output should be presented.
Moreover, manifestations such as “emotional manipulation” or the presentation of “overly specific trivia” 1 are particularly noteworthy. These mimic sophisticated, and sometimes flawed, human communication patterns. This suggests that the model is not only learning factual information (or misinformation) but also stylistic and rhetorical elements from its vast training corpus of human text. However, it learns these patterns without the corresponding human understanding of context, intent, or ethical appropriateness. An LLM might adopt an emotional tone or deploy a highly specific (but false) detail simply because such stylistic choices are statistically associated with persuasive or informative text in its training data, rather than from any genuine understanding or intent to deceive. This highlights a deeper challenge: as AI becomes more adept at mimicking not just the content but also the style of human communication, its capacity for unintentional (or potentially intentional, if misused) deception increases. This also makes the detection of such subtle AI hallucinations more difficult for users.
2.1.2.AI Hallucinations in Multimodal Systems (e.g., Text-to-Image, Text-to-Video, MLLMs)
Multimodal AI systems, which process and generate information across different data types (e.g., text, images, video, audio), introduce new dimensions to the AI hallucination problem. Here, hallucinations often manifest as inconsistencies or misalignments between modalities.
- Text-to-Image and Text-to-Video Generation: These models can produce visual content that deviates significantly from the textual prompt.12 In video generation, this can include 12:
- Unrealistic Motion: Objects moving in physically impossible ways.
- Object Inconsistency: Sudden changes in an object’s appearance, shape, or color across frames.
- Physics Violations: Scenes that contradict fundamental laws of physics.
- The ViBe benchmark provides a structured categorization of text-to-video hallucinations 12:
- Vanishing Subject: The primary subject or parts of it randomly disappear and reappear (e.g., a piece of food vanishing as a character attempts to eat it).
- Omission Error: Essential elements described in the prompt are missing from the generated video (e.g., a prompt asking for “a cat chasing a mouse” generates a video with only a cat).
- Numeric Variability: The number of objects or subjects depicted does not match the number specified in the prompt (e.g., a prompt for “three birds” results in a video with five birds).
- Subject/Temporal Dysmorphia: Objects undergo continuous and unnatural deformations in shape, size, or orientation over time (e.g., a person’s limbs elongating or shrinking bizarrely as they move).
- Visual/Physical Incongruity: The video depicts elements that violate physical laws or are contextually incongruous (e.g., an animal appearing to be made of stone and floating above a crowd, when the prompt described it walking among them).
- Multimodal Large Language Models (MLLMs) / Large Vision-Language Models (LVLMs): These models, designed for tasks like image captioning or visual question answering, can generate textual outputs that are inconsistent with the provided visual input.17 A key area of concern is object hallucination, which is often categorized as follows 17:
- Category Hallucination: The MLLM identifies or describes object categories that are non-existent in the image or misidentifies present objects. For example, a model might describe “benches and a fence” in an image of a park scene where no such objects are visible.18
- Attribute AI Hallucination: The model correctly identifies an object but incorrectly describes its attributes, such as color, shape, material, count, or associated actions. For instance, an MLLM might describe “pink blossoms” on a tree when the blossoms in the image are clearly white 18, or it might incorrectly state the number of objects present.18 Another example is a model confusing red elements on a bus with an entirely separate red car that is not present.19
- Relation AI Hallucination: The model accurately describes individual objects and their attributes but misrepresents the spatial, functional, or interactive relationships between them. For example, an image might show several people in a park and a girl with outstretched arms, and the MLLM might generate a caption stating these people are “standing around her, watching,” when the visual evidence does not support this specific interaction or grouping.18
- General Visual Artifacts: Beyond semantic misalignments, AI-generated visual content can suffer from various artifacts. Deepfake videos, for instance, may exhibit subtle visual anomalies such as inconsistencies in facial features (e.g., unnatural eye movements, distorted mouth shapes during speech), jerky or unnatural body movements, or poor lip-syncing with the audio.20 Generated images can also contain errors like distorted human fingers (a common example being an incorrect number of fingers, such as six fingers on one hand, categorized as a “Duplication” artifact) or other forms of “Distortion”.21
The core challenge in multimodal systems often revolves around achieving and maintaining cross-modal consistency.17 AI Hallucinations in this context represent a fundamental failure of the model to create a coherent, unified internal representation from disparate information streams or to faithfully translate intent from one modality to another. This points to the profound difficulty in truly “fusing” modalities in a way that mirrors human holistic understanding, rather than merely processing them in parallel or through superficial connections. Unlike an LLM hallucinating a fact for which there might be no immediate external reference in the prompt, MLLMs often hallucinate in tasks like image captioning or visual question answering where an external visual ground truth is provided as part of the input. The hallucination, in this case, is a failure to faithfully represent, interpret, or reason about this provided visual information. This suggests that the bottleneck may lie in how visual features are encoded and translated into a “language” that the LLM component can effectively process, or vice-versa in text-to-visual generation. Consequently, research must focus not only on improving unimodal encoders (for vision, text, etc.) but critically on the interface and fusion mechanisms between modalities.
The prevalence of “Physical Incongruity” and “Temporal Dysmorphia” in AI-generated video 12 is particularly revealing. These types of hallucinations highlight a significant deficit in ingrained “common sense physics”—an intuitive understanding of object permanence, consistent motion, gravity, and material properties that humans develop through interaction with the physical world. Current models, often trained predominantly on static images or limited-duration video clips, appear to learn statistical correlations of visual appearances rather than the underlying generative principles of the physical world. They become adept at mimicking “what things look like” but struggle with “how things work” or “how things move and interact realistically over time.” To generate truly realistic and reliable video content, future models may need to incorporate more explicit physical reasoning capabilities, learn from much richer and more diverse dynamic world data, or develop architectures that can better infer and apply these implicit physical rules. This represents a challenge that goes beyond simply improving frame-by-frame image generation quality.
Evaluating AI hallucinations in multimodal systems also presents unique and significant challenges.12 Defining “ground truth” or “correctness” is inherently more complex for generative visual tasks than for factual text generation. For example, is a generated image “correct” if it semantically aligns with the text prompt but contains subtle visual artifacts or appears uncanny? Assessing multimodal outputs requires evaluating multiple dimensions simultaneously: semantic alignment with textual descriptions, visual fidelity and realism, temporal coherence and consistency (for video), physical plausibility, and the absence of specific, distracting artifacts. Existing automated metrics often struggle to capture all these nuances, and human evaluation, while more comprehensive, is expensive and time-consuming to scale. This underscores a critical need for the development of more sophisticated, perceptually-aligned evaluation benchmarks and automated metrics for multimodal AI, with ongoing efforts like the ViBe benchmark 12 and new metrics 22 attempting to address this gap.
To provide a clearer overview of these diverse manifestations, Table 1 offers a typology of AI hallucinations.
Table 1: Typology of AI Hallucinations: Manifestations and Examples in LLMs and Multimodal Systems.
AI Modality | Hallucination Category/Type | Detailed Manifestation | Concrete Example | Key Sources |
LLMs | Factual Error/Inaccuracy | Generates statements that are verifiably false regarding events, facts, or figures. | LLM states Google’s Bard claimed the James Webb Space Telescope took the first exoplanet image, when it was taken years prior by another telescope.23 | 1 |
Nonsensical/Incoherent Output | Produces text that lacks logical consistency or relevance to the prompt, despite grammatical correctness. | An LLM providing a recipe with non-existent ingredients or self-contradictory instructions. | 1 | |
Fabricated Content/Sources | Invents details, events, or sources that do not exist. | ChatGPT fabricating non-existent legal case citations for a lawyer’s motion.10 | 1 | |
MLLMs / LVLMs | Object Category Hallucination | Identifies or describes objects in an image that are not present, or misclassifies existing objects. | MLLM describes “some benches and a fence” in an image where these objects do not exist.18 | 17 |
Object Attribute Hallucination | Correctly identifies an object but provides inaccurate descriptions of its attributes (color, shape, count, etc.). | MLLM describes “pink blossoms” on a tree when the blossoms in the image are white.18 | 17 | |
Object Relation Hallucination | Accurately describes objects and attributes but misrepresents the relationships or interactions between them. | MLLM describes people in an image as “standing around her, watching…” when the visual does not support this specific interaction.18 | 17 | |
Text-to-Image | Visual Discrepancy/Artifact | Generates images with elements that misalign with the prompt, or contain visual errors like distorted features. | An image generated for “a person holding a cat” shows the person with six fingers on one hand.21 | 12 |
Text-to-Video | Vanishing Subject | A key subject in the video randomly disappears and reappears without logical reason. | In a video of “a man scooping food,” the food disappears from his hand as it approaches the pan.15 | 12 |
Omission Error | Fails to include essential components or actions described in the prompt. | Prompt: “A baby elephant walking behind a large one.” Video shows only the large elephant, omitting the baby.15 | 12 | |
Numeric Variability | The number of subjects or objects depicted in the video does not match the number specified in the prompt. | Prompt: “Six people around a kiln.” Video depicts only two people.15 | 12 | |
Subject/Temporal Dysmorphia | Objects undergo continuous, unnatural deformation in shape, size, or orientation over time. | A character in a video swinging a tennis racket experiences bizarre distortions in their limbs and the racket itself during the motion.15 | 12 | |
Visual/Physical Incongruity | Generated video violates fundamental physical laws or places incongruent elements together, creating inconsistencies. | An animal prompted to be “walking in a crowd” appears to be made of stone and positioned unnaturally above the crowd.15 | 12 |
2.2. Core Technical Drivers of Hallucinations
AI hallucinations are not arbitrary; they stem from identifiable technical issues within the AI development and operational pipeline. These can be broadly categorized into data-related problems, model-specific limitations, and issues arising from inference mechanisms and a lack of grounding.
2.2.1. Data-Related Issues: Quality, Bias, and Incompleteness
The quality, composition, and characteristics of the data used to train AI models are paramount and represent a primary source of hallucinations.4 Several data-related factors contribute significantly:
- Inaccurate or Noisy Data: If the training dataset contains factual errors, mislabeled examples, or irrelevant noise, the model will inevitably learn these inaccuracies and reproduce them as hallucinations.4 The sheer volume of data scraped from the internet for training large models makes it virtually impossible to ensure perfect accuracy and cleanliness.
- Incomplete or Sparse Data: When training data lacks comprehensive coverage of certain topics, concepts, or scenarios, the model is forced to “fill in the gaps” when queried about these areas. This often involves making assumptions or extrapolations that can lead to fabricated or incorrect information.2 This is particularly problematic for “long-tail” phenomena—rare events, niche topics, or underrepresented entities—where data sparsity is common. Models may perform well on common concepts but exhibit higher AI hallucination rates when dealing with these less frequently observed instances because they lack sufficient examples to form a robust understanding.
- Outdated Data: AI models are typically trained on static datasets. If this data becomes outdated (e.g., new scientific discoveries are made, current events change), the model’s knowledge will not reflect the current state of affairs, leading it to provide responses that are no longer relevant or factually correct.4
- Biased Data: Training datasets often reflect existing societal biases related to gender, race, culture, or other characteristics. Models trained on such data can internalize these biases and generate outputs that favor certain perspectives, perpetuate stereotypes, or produce discriminatory outcomes.4 This is not merely about factual incorrectness; it can lead to “representational hallucinations,” where models fail to generate or acknowledge certain groups or concepts, or consistently produce stereotypical and harmful representations, effectively hallucinating a skewed version of reality. This has profound ethical implications for how AI might shape or reinforce societal perceptions.
- Irrelevant or Misleading Data: Including data that is not pertinent to the model’s intended tasks can confuse it, while data that is deliberately or inadvertently misleading can steer the model towards incorrect conclusions.4
- Duplicated and Poorly Structured Data: Excessive repetition of certain facts or data points can cause the model to overemphasize them, while disorganized or poorly structured data makes it difficult for the model to discern clear patterns and relationships, potentially leading to confused or erroneous outputs.4
- Lack of Data Diversity: Insufficient diversity in training data, such as underrepresentation of certain demographic groups, dialects, or rare conditions (e.g., in medical AI), limits the model’s ability to generalize, often resulting in poorer performance and higher hallucination rates for these underrepresented cases.26
2.2.2. Model-Related Issues: Architecture, Overfitting, and Training Deficiencies
Beyond the data itself, the characteristics of the AI model—its architecture, how it is trained, and its inherent limitations—play a crucial role in the genesis of hallucinations.
- Poor Model Design/Architecture: If a model’s architecture lacks the necessary complexity or appropriate mechanisms to capture the nuances of the data or the task (e.g., understanding long-range dependencies in text, fusing multimodal information effectively), it may generate overly simplistic, contextually inappropriate, or factually incorrect outputs.4 Hardware limitations, such as inadequate processing power or memory, can also force models to simplify outputs during inference, potentially contributing to hallucinations.4
- Overfitting and Underfitting: Overfitting is a common problem where a model learns the training data too well, including its noise and specific idiosyncrasies, rather than the underlying generalizable patterns.2 An overfit model may perform exceptionally well on data it has seen during training but poorly on new, unseen data, often by generating content that is specific to training examples but out of context or fabricated for novel inputs. Conversely, underfitting occurs when the model fails to capture sufficient detail from the training data, also leading to unreliable and potentially hallucinated outputs.4
- Inadequate or Flawed Training: If the training process itself is deficient—for example, if the training data lacks diversity, or if the learning objectives do not sufficiently penalize falsehoods—the model may develop knowledge gaps or learn to prioritize fluency over accuracy. These gaps are then often filled with assumptions or fabrications during inference.4
- Overconfidence and Poor Calibration: A significant issue with many LLMs is their tendency to exhibit overconfidence, generating outputs with a high degree of certainty even when the information is incorrect or entirely hallucinated.26 This poor calibration—where the model’s expressed confidence does not align with the actual probability of its prediction being correct—can mislead users into trusting inaccurate outputs. This often stems from training objectives (like maximizing the likelihood of the next token) that do not explicitly train the model for calibrated uncertainty. The model learns to produce fluent and assertive-sounding output because such styles are prevalent in its training data, irrespective of the factual correctness of a specific generated instance. Developing methods for reliable uncertainty estimation and calibration is therefore paramount; models should be capable of, and incentivized to, express low confidence or explicitly state “I don’t know” rather than confidently fabricating an answer.
- Model Capacity and AI Hallucination Proneness: The relationship between model capacity (e.g., the number of parameters) and its tendency to hallucinate is complex. While larger models can store more knowledge and generate more coherent and nuanced content, their increased capacity might also allow them to memorize a greater number of spurious correlations from noisy data or to generate more elaborate and internally consistent—yet factually incorrect—hallucinations. There isn’t a simple monotonic relationship where “bigger is always better” or “smaller is always safer.” The specific architecture, the quality of training data, regularization techniques, and the training objectives all interact in intricate ways. A very large model trained on vast, noisy internet data might be a prolific AI hallucinator if not properly constrained, whereas a smaller, well-regularized model trained on high-quality, curated data might be more robust against certain types of hallucinations but less capable overall. Research must explore architectural choices and training strategies that allow for the scaling of knowledge representation and reasoning capabilities without a proportional increase in hallucination risk.
2.2.3. Inference Mechanisms and Lack of Grounding
The way an AI model generates its output at inference time, coupled with its fundamental lack of true understanding or grounding in the real world, are also key contributors to hallucinations.
- Probabilistic Generation and Gap Filling: AI models, particularly generative ones, do not “think” or “understand” in a human sense; they predict the next token (word, pixel, etc.) in a sequence based on statistical patterns learned during training.4 When faced with ambiguity or a lack of specific information for a given prompt, they attempt to “fill in the gaps” by generating the most statistically plausible continuation. This process can lead to the creation of content that sounds coherent but is factually baseless.
- Inherent Complexity of Natural Language and Context: Natural language is replete with nuances, ambiguities, context dependencies, and idiomatic expressions that are exceedingly difficult for AI systems to fully grasp.8 A model’s failure to correctly interpret subtle contextual cues can lead to responses that are irrelevant, ungrounded, or nonsensical.
- Lack of Real-World Understanding and Common Sense: Many AI models lack a robust understanding of the real world, including basic common-sense knowledge about physical laws, causality, social dynamics, or typical properties of objects.2 This deficit means they can generate outputs that, while perhaps linguistically or visually plausible in isolation, are physically impossible, socially inappropriate, or logically absurd in the context of the real world (e.g., a character in a 1960s setting using a modern cellphone 8). This “lack of grounding” extends beyond factual knowledge to encompass implicit knowledge of how the world works. This is particularly evident in multimodal hallucinations, such as the “physical incongruity” observed in AI-generated videos where objects defy gravity or move in impossible ways.12 Current models, trained primarily on observational data like text and images, do not inherently learn these underlying generative rules of the world. They learn correlations (e.g., object A often appears with object B) but not necessarily causation (e.g., action X causes outcome Y) or fundamental constraints (e.g., object Z cannot pass through solid object W without consequence). Achieving AI that doesn’t hallucinate in these ways may require incorporating methods that allow models to learn or access these causal and physical models of the world, perhaps through integration with simulators, interactive learning environments, or structured knowledge bases.
- Decoding Strategies: The specific algorithms used during inference to select the output sequence from the model’s probability distribution (known as decoding strategies) can significantly influence the likelihood of hallucinations.2 For example, greedy decoding (always picking the most probable next token) can lead to repetitive or dull output, while sampling-based methods (which introduce randomness to promote diversity and creativity) can increase the chance of the model veering into less probable, ungrounded, or nonsensical territory.3 This presents a direct trade-off: strategies that enhance creativity and diversity may also heighten the risk of hallucination. There is no single “best” decoding strategy for all applications; the choice must be tailored to the specific use case and the acceptable level of risk.
- Sensitivity to Environmental Changes: Models are often sensitive to the context in which they operate. If the operational environment shifts significantly from the training environment (e.g., encountering new topics, unforeseen scenarios, or different data distributions), the model may struggle to generalize and generate errors or hallucinations because it hasn’t been trained on such novel information.4
Table 2 provides a structured summary of these core technical drivers.
Table 2: Key Technical Causes of AI Hallucinations and Contributing Factors.
Causal Category | Specific Contributing Factor | Description of Contribution to Hallucinations | Key Sources |
Data-Related Issues | Inaccurate/Noisy Training Data | Model learns from erroneous or irrelevant information, leading to the generation of incorrect or nonsensical outputs. | 4 |
Incomplete/Sparse Training Data | Missing information forces the model to fill gaps with assumptions or fabrications, especially for rare or out-of-distribution queries. | 2 | |
Outdated Training Data | Model provides responses based on information that is no longer current or relevant, leading to factual inaccuracies. | 4 | |
Biased Training Data | Model learns and reproduces societal biases present in data, leading to skewed, stereotypical, or discriminatory outputs. | 4 | |
Poorly Structured/Duplicated Data | Disorganized data hinders pattern learning; repetition can overemphasize certain facts, leading to skewed or irrelevant outputs. | 4 | |
Model-Related Issues | Poor Model Design/Architecture | Architectural limitations prevent the model from capturing complex context or relationships, resulting in flawed outputs. | 4 |
Overfitting | Model memorizes training data noise and specific examples instead of generalizing, leading to fabrications for unseen inputs. | 4 | |
Underfitting | Model fails to capture sufficient detail from training data, resulting in overly simplistic or inaccurate outputs. | 4 | |
Inadequate Training/Objectives | Deficiencies in the training process or objectives (e.g., prioritizing fluency over factuality) lead to knowledge gaps and flawed learning. | 4 | |
Overconfidence/Poor Calibration | Model generates incorrect information with high certainty, misleading users due to a mismatch between confidence and actual accuracy. | 26 | |
Inference/Grounding Issues | Probabilistic Generation | Model predicts statistically likely sequences rather than reasoning, leading to plausible but baseless fabrications to fill information gaps. | 4 |
Lack of Real-World Understanding | Absence of true comprehension of concepts, causality, or physical laws allows generation of nonsensical or impossible scenarios. | 2 | |
Lack of Common Sense | Model generates outputs that violate basic common sense, often due to an inability to apply implicit world knowledge. | 8 | |
Flawed Decoding Strategies | Inference-time choices (e.g., excessive randomness in sampling) can lead the model to generate less factual or coherent content. | 2 | |
Sensitivity to Context/Prompt | Misinterpretation of complex language nuances or sensitivity to slight variations in input can lead to ungrounded responses. | 8 |
2.3. High-Risk Domains: Where AI Hallucinations Pose the Greatest Threats
The impact of AI hallucinations is not uniform across all applications. In domains where decisions carry significant weight and errors can lead to severe or irreversible consequences, hallucinations pose the most substantial threats. Key high-risk sectors include:
- Healthcare: This is arguably one of the most critical domains. AI hallucinations can lead to misleading diagnoses, incorrect treatment recommendations (e.g., wrong medication dosages or identification of drug interactions), the dissemination of harmful medical advice, or the fabrication of patient information within clinical notes.9 The case of “Tessa,” an AI-powered mental health chatbot that provided harmful advice to users with eating disorders, starkly illustrates the potential for direct patient harm.9 Even minor inaccuracies can erode clinician trust and compromise patient safety. The implicit authority often granted to AI-generated outputs can be particularly dangerous in healthcare, where patients or even time-pressed clinicians might overly trust AI-generated advice, especially if they lack deep domain expertise to critically evaluate it.26
- Law: In the legal field, AI hallucinations can distort legal arguments, lead to the citation of fabricated legal precedents, and ultimately contribute to miscarriages of justice.9 There have been multiple reported instances where lawyers were sanctioned for submitting court filings containing fake case citations generated by LLMs like ChatGPT.9 Such errors not only damage the credibility of the legal professionals involved but also undermine the integrity of the judicial process itself. The reliance of common law systems on precedent makes them uniquely vulnerable; a single, undetected hallucinated citation could theoretically influence legal arguments and decisions with cascading effects.
- Finance: AI-generated misinformation can significantly impact financial decisions, leading to substantial economic losses, market volatility, and reputational damage for companies.9 A prominent example is the reported $100 billion loss in market value for Alphabet Inc. after its Bard AI shared inaccurate information during a promotional demonstration.9 AI Hallucinated financial advice or predictions, if acted upon, can have severe consequences for individuals and institutions.
- Journalism and Information Ecosystem: The capacity of AI to fabricate false news, create convincing deepfakes, and generate plausible-sounding misinformation poses a direct threat to the integrity of the information ecosystem.9 This can manipulate public opinion, interfere with democratic processes (as seen with AI-driven robocalls impersonating political figures 29), and erode public trust in media and institutions.
- Cybersecurity: In this domain, AI hallucinations can manifest in several dangerous ways. They might cause security systems to overlook genuine threats (false negatives, often due to biases in training data) or, conversely, to generate false alarms that waste resources and lead to alert fatigue among security personnel.24 AI might also provide inaccurate recommendations during incident response, prolonging detection or recovery times. Furthermore, AI tools used for code generation could mislead developers into deploying code with hidden vulnerabilities, effectively creating new attack vectors.9
A critical concern across these high-risk domains is the potential for systemic risk. If multiple actors within a sector (e.g., several hospitals, law firms, or financial institutions) begin to rely on the same few dominant, hallucination-prone foundational AI models, they could all become susceptible to similar patterns of error. This could lead to correlated failures across the system—multiple doctors making similar misdiagnoses based on flawed AI advice, or numerous lawyers citing the same fabricated legal precedent. Such systemic vulnerabilities necessitate diversity in AI models and approaches, robust independent validation of AI tools before widespread adoption in critical sectors, and mechanisms for sharing information about discovered flaws or common hallucination patterns. AI hallucinations in these sectors can lead to client harm resulting in legal sanctions and economic losses.
2.4. Current Mitigation Strategies: An Overview and Their Limitations
Given the risks posed by AI hallucinations, significant effort is being directed towards developing strategies to mitigate their occurrence and impact. Systemic vulnerabilities arising from shared AL hallucinations necessitate diversity in models, redundancy in tools, and oversight. These strategies span various stages of the AI lifecycle, from data preparation to model deployment and use. General approaches include:
- Improving Training Data Quality: This is a foundational step, involving the use of reliable, diverse, relevant, and specific data sources. Efforts focus on cleaning data, reducing noise and bias, ensuring data is up-to-date, and structuring it effectively.2
- Selecting Appropriate AI Models: Choosing models best suited for the specific task can improve performance and reduce errors. For instance, more advanced or specialized models might be preferred for complex tasks requiring high fidelity.23
- Prompt Engineering: Carefully crafting the input prompts given to generative AI can significantly influence output quality. Techniques include providing explicit instructions, using “chain of thought” prompting (asking the model to explain its reasoning step-by-step), supplying examples of desired outputs, providing full context for the query, and explicitly instructing the model on what not to do or that providing no answer is preferable to an incorrect one.2
- Reinforcement Learning from Human Feedback (RLHF): This technique involves training models using feedback from human evaluators who rate or correct AI-generated responses. This helps align the model’s outputs with human preferences for accuracy, harmlessness, and helpfulness.23
- Human Oversight and Output Validation: Implementing a human-in-the-loop system, where humans review and validate AI outputs, especially for critical decisions or in high-stakes applications, is a crucial safeguard.23 This includes fact-checking AI-generated claims against trusted sources.
- Retrieval-Augmented Generation (RAG): RAG systems enhance LLMs by allowing them to access and incorporate information from external, up-to-date, and trusted knowledge bases before generating a response. The aim is to ground the model’s output in verifiable facts.25
- Architectural and Training Modifications: This includes techniques like regularization to prevent overfitting 2, using predefined templates to structure outputs 2, and designing model architectures that are inherently less prone to certain types of errors.
- Fact-Checking Mechanisms and Plug-ins: Integrating automated fact-checking tools or browser plug-ins that can verify information in real-time or cross-reference claims against databases.30
- Increasing User Awareness and AI Literacy: Educating users about the capabilities and limitations of AI, including its propensity to hallucinate, can help them interact with these systems more critically and cautiously.30
Despite this growing toolkit of mitigation strategies, it is crucial to recognize their limitations. No single strategy, nor any current combination, can completely eliminate AI hallucinations.5 For example:
- RAG systems are dependent on the quality and coverage of their retrieval database; if the retrieved information is itself flawed, outdated, or incomplete, the RAG system may still produce hallucinations or fail to find relevant grounding information.5 There’s also the risk of over-reliance on retrieved information, where the model might still hallucinate if the retrieval yields ambiguous or empty results.
- Advanced models often come with trade-offs such as increased computational cost, higher latency, and, in some cases, studies have indicated potential drops in accuracy on certain tasks compared to their predecessors.30
- Prompt engineering, while powerful, is often more of an art than a science and does not guarantee correct results across all scenarios; its effectiveness can be highly task-dependent and require significant expertise.30
- RLHF is heavily reliant on the quality, consistency, and diversity of human feedback, which can be expensive to obtain at scale and may itself introduce new biases if not carefully managed.23
- Human oversight, while often considered the gold standard for verification, is resource-intensive, can be slow, and is not always scalable for the vast amounts of content AI can generate.23
- Improving data quality is an ongoing and immense challenge, especially for models trained on web-scale datasets. Ensuring data is truly representative, unbiased, and factually accurate across all domains is practically infeasible.11
- Fundamentally, issues like overfitting and faulty model assumptions related to the model’s internal workings remain persistent challenges.11
Many current mitigation techniques function as “patches” or “guardrails” applied to inherently probabilistic models, rather than addressing the fundamental reasons why hallucinations occur. These strategies are largely reactive or aim to constrain output, but they do not fundamentally alter the core mechanisms of how these models learn or “reason.” This suggests that the field is still in a relatively early phase of tackling the hallucination problem. Long-term solutions will likely necessitate more fundamental breakthroughs in AI architectures (e.g., neuro-symbolic AI, causal AI), learning paradigms that go beyond statistical pattern matching, and training objectives that explicitly optimize for truthfulness, verifiable reasoning, and robust uncertainty estimation.
Furthermore, the efficacy of many mitigation techniques—such as prompt engineering, the curation of RAG databases, and the provision of feedback for RLHF—relies heavily on human expertise, effort, and judgment. This reliance creates potential bottlenecks in terms of scalability and cost, and also re-introduces the possibility of human bias or error into the mitigation process itself. For example, biased human feedback could inadvertently steer an RLHF-trained model towards new, unforeseen biases. While human-in-the-loop approaches are currently indispensable, there is a clear need for research into more automated, scalable, and robust mitigation techniques that are less dependent on constant and perfect human intervention. This also highlights the importance of training humans to effectively perform these oversight, feedback, and verification roles.
Table 3 summarizes these general mitigation strategies, their perceived effectiveness, and inherent limitations.
Table 3: Overview of General AI Hallucination Mitigation Strategies, Their Effectiveness, and Limitations.
Mitigation Strategy | Description of Strategy | General Effectiveness | Key Limitations | Key Sources |
Enhanced Data Quality | Curating diverse, accurate, relevant, and up-to-date training datasets; reducing bias and noise. | Can significantly reduce data-driven errors and improve model grounding in factual information. | Difficult to eliminate all bias/errors in web-scale datasets; ensuring true representativeness is challenging; data can become outdated. | 11 |
Prompt Engineering | Crafting specific, contextual, and well-structured prompts to guide model output and constrain its scope. | Effective for guiding output for specific tasks and reducing ambiguity; can elicit more factual responses. | Not a universal fix; highly dependent on prompt quality and user skill; may not prevent all types of hallucinations, especially complex fabrications. | 25 |
RLHF | Incorporating human feedback to fine-tune model responses for accuracy, safety, and alignment with desired behaviors. | Improves model alignment with human preferences; can reduce harmful or nonsensical outputs. | Scalability and cost of human feedback; potential for rater bias or inconsistency; may not generalize well to out-of-distribution prompts. | 23 |
RAG | Grounding model responses by retrieving relevant information from trusted external knowledge bases at inference time. | Can significantly improve factual accuracy and reduce fabrication by providing verifiable context. | Effectiveness depends on retriever quality and knowledge base coverage/accuracy; can still hallucinate if retrieved info is flawed, missing, or misinterpreted by the LLM. | 5 |
Advanced Model Architectures/Choice | Selecting more sophisticated models or architectures designed to better handle complexity or specific tasks. | Newer/larger models may have better reasoning or knowledge capabilities, potentially reducing some types of errors. | Higher cost, latency; may introduce new types of errors or trade-offs; “more advanced” doesn’t always mean less prone to all hallucinations. | 23 |
Human Oversight/Validation | Employing human reviewers to check and verify AI-generated content before use, especially in critical applications. | Can catch many hallucinations before they cause harm; provides a crucial safety net. | Resource-intensive (time, cost); not scalable for all applications; subject to human error or fatigue. | 23 |
Regularization/Output Limiting | Techniques to prevent overfitting or constrain the range of possible outputs the model can generate. | Can improve generalization and reduce extreme or nonsensical predictions. | May limit model creativity or expressiveness; finding the right balance can be difficult. | 2 |
Using Templates | Providing structured templates for the AI to follow, especially for tasks requiring specific output formats. | Helps ensure consistency and adherence to desired structure, reducing some types of formatting errors or irrelevant content. | May be too rigid for tasks requiring flexibility or creativity; doesn’t address underlying factual inaccuracies. | 2 |
Fact-Checking Plug-ins | Integrating external tools that automatically verify factual claims made by the AI. | Can provide real-time checks for certain types of factual statements. | Coverage of fact-checking databases may be limited; may not catch nuanced or context-dependent falsehoods; potential for false positives/negatives from the checker itself. | 30 |
User Awareness/AI Literacy | Educating users about AI limitations and the possibility of hallucinations. | Empowers users to critically evaluate AI outputs and use them more responsibly. | Relies on user diligence; may not be sufficient for users lacking expertise or in situations requiring rapid decisions. | 30 |
3. Deep Dive: Real-World Consequences and Ethical Risks of AI Hallucinations
While the technical underpinnings and general mitigation strategies for AI hallucinations are subjects of ongoing research, the immediate and tangible impacts of these phenomena are already being felt across various sectors. This section delves into documented case studies illustrating these negative consequences and provides a broader analysis of the profound ethical risks that arise, particularly when hallucination-prone AI systems are deployed in high-stakes environments.
3.1. Documented Impacts: Case Studies of AI Hallucinations
The theoretical potential for harm from AI hallucinations becomes concrete when examining real-world incidents. These cases underscore the diverse ways in which plausible but false AI outputs can lead to detrimental outcomes.
3.1.1. Healthcare: Misdiagnosis, Patient Safety, and Erroneous Medical Advice
In the healthcare domain, where accuracy and reliability are paramount, AI hallucinations can have direct and severe consequences for patient well-being. Instances have been documented where AI systems generated incorrect information regarding medication dosages, potential drug interactions, or diagnostic criteria, any of which could lead to life-threatening outcomes if acted upon.26 LLMs have been observed to hallucinate patient information, including medical history or symptoms that were not present in the original patient notes, thereby risking the formulation of inappropriate treatment protocols.26
Documented instances of AI hallucinations include systems generating incorrect information regarding medication dosages and diagnostic criteria. A stark example is the case of “Tessa,” an AI-powered mental health chatbot, which was shut down after it was found to be providing harmful advice to users with eating disorders.9 This incident highlights the particular vulnerability of patients seeking help for sensitive conditions and the grave responsibility incumbent upon developers of medical AI. Even sophisticated models like GPT-4o, while demonstrating general accuracy in tasks such as recognizing medications from images, have shown imperfections where information provided was incomplete or lacked clarity regarding crucial administration steps, potentially impacting patient education and safe use.31 A 2023 study investigating references in medical articles generated by ChatGPT found that only a mere 7% were authentic and accurate, with a staggering 47% being entirely fabricated and another 46% being authentic but completely inaccurate in context.5
The “illusion of understanding” caused by AI hallucinations in medical systems can be particularly perilous. A model might correctly identify some symptoms or utilize appropriate medical terminology, giving an impression of competence, yet fundamentally misunderstand the patient’s overall condition or fail to consider critical contraindications. This can lead to advice that sounds plausible and medically informed but is dangerously flawed. Patients, often lacking deep medical expertise and perhaps seeking quick answers due to anxiety, are especially vulnerable to being misled by such superficially coherent but incorrect AI-generated medical advice.26 This creates a significant power imbalance and underscores a profound ethical imperative to design medical AI with robust safeguards, transparent disclaimers about its limitations, and clear guidance directing users towards professional human consultation, especially when dealing with vulnerable populations or serious health concerns.
3.1.2. Legal Sector: Fabricated Precedents, Miscarriage of Justice, and Professional Misconduct
The legal profession has also witnessed significant disruptions due to AI hallucinations in legal research and findings. There have been multiple high-profile cases where lawyers submitted court filings containing fictitious case citations generated by AI tools, leading to judicial sanctions, fines, and considerable embarrassment for the legal professionals and firms involved.9 For example, a lawyer in New York was fined after ChatGPT fabricated six non-existent legal citations in a court submission.10 In another instance, attorneys from the prominent law firm Morgan & Morgan reportedly used an AI tool that generated entirely non-existent legal precedents in a lawsuit against Walmart.10 Over a two-year period, at least seven such cases involving lawyers submitting AI-generated hallucinations in legal documents have been reported.10 As a consequence, courts have begun to scrutinize AI-generated content in filings more rigorously, sometimes demanding explicit confirmation of AI use and verification of all AI-generated citations.10
These incidents demonstrate how AI hallucinations can directly undermine the integrity of the legal process, waste valuable court time and resources, and severely damage the credibility and reputation of legal professionals. The common law system’s heavy reliance on precedent (stare decisis) makes it uniquely vulnerable to the introduction of fabricated case law. A single convincingly crafted but entirely false precedent, if it goes undetected by opposing counsel or the judiciary, could theoretically influence legal arguments, sway judicial decisions, and create a ripple effect of erroneous legal reasoning. This poses a fundamental threat to the stability and reliability of the legal system.
The combination of the “black box” nature of many AI tools 9—where their internal reasoning processes are opaque—and the increasing pressure for efficiency in legal practice creates a fertile ground for such risks. Lawyers, particularly those who are less experienced, under tight deadlines, or in high-volume practices, might be tempted to use AI tools to expedite research without fully understanding their potential for error or possessing adequate skills for verifying the outputs.11 The allure of speed could inadvertently override the diligence required for accuracy. This situation necessitates urgent updates to legal education and continuing professional development programs to include comprehensive AI literacy, focusing on the risks of hallucination and robust methods for verification. Law firms also need to establish clear internal policies regarding the use of AI in legal work, emphasizing that accuracy and ethical responsibility must always take precedence over speed.
3.1.3. Journalism and Information Ecosystem: Proliferation of Misinformation, Deepfakes, and Erosion of Media Integrity
In the domain of journalism and the broader information ecosystem, AI hallucinations pose a severe threat by enabling the rapid creation and dissemination of false news, convincing deepfakes, and other forms of misinformation.9 A notable example of AI being used for manipulative purposes was the AI-driven robocalls that impersonated President Joe Biden during the 2024 New Hampshire primary, aiming to dissuade voters from participating.29 Such incidents highlight the ease with which AI can be weaponized to interfere in sensitive political processes. While media coverage often spotlights AI errors, which can sometimes fuel public mistrust in AI technologies more broadly 29, the core issue is the potential for AI-generated falsehoods to pollute the information landscape, making it harder for citizens to discern truth from fiction.
The speed and scale at which AI can generate plausible-sounding misinformation present an unprecedented challenge to traditional fact-checking mechanisms and journalistic ethics. Human-based reporting, editing, and fact-checking processes have inherent time constraints. AI, on the other hand, can produce and disseminate vast quantities of customized, convincing misinformation much faster than human systems can identify, analyze, and debunk it. This creates a dangerous information asymmetry that can be exploited by malicious actors.
A significant societal consequence of AI hallucinations is the rise of the “liar’s dividend,” where trust in real media erodes.29 As the public becomes increasingly aware that AI can create highly realistic but false content (images, videos, audio, text), a pervasive cynicism about all digital information can take root. This phenomenon allows malicious actors to more easily dismiss genuine evidence of wrongdoing (e.g., an authentic incriminating video or document) by simply claiming it is an “AI deepfake.” This undermines accountability, makes it harder to establish a shared understanding of reality in public discourse, and erodes trust not only in media but in all forms of digital communication. Combating this requires a multi-faceted approach involving technological solutions for detecting fakes, robust public education initiatives focused on digital and media literacy, and potentially new legal and regulatory frameworks for authenticating digital content in high-stakes contexts and penalizing the malicious creation and spread of AI-generated disinformation.
3.1.4. Finance and Business: Reputational Damage, Economic Losses, and Erroneous Decision-Making
The financial and business sectors are also susceptible to the adverse effects of AI hallucinations, which can translate directly into tangible economic losses, significant reputational damage, and flawed strategic decision-making. As previously mentioned, an error made by Google’s Bard AI regarding a discovery by the James Webb Space Telescope reportedly led to a $100 billion drop in Alphabet Inc.’s market value, illustrating the market’s sensitivity to perceived AI failures.9 In a different type of incident, Air Canada faced legal repercussions and reputational harm when its customer service chatbot hallucinated incorrect refund policies, which the company was subsequently compelled to honor.25 Such cases demonstrate that misleading promises or incorrect information provided by AI systems (e.g., regarding refunds, product features, or service eligibility) can lead to direct financial liabilities for businesses or a significant loss of customer loyalty and trust.25
The significant stock market reaction to AI errors, like the Bard incident, suggests a high degree of sensitivity and perhaps overly inflated expectations regarding the current state of AI performance and reliability. This can create immense pressure on companies developing and deploying AI to demonstrate flawless capabilities, which may be unrealistic given the inherent probabilistic nature of current generative models and their known propensity for hallucination. Such market pressure could inadvertently lead to rushed deployments, downplaying of risks, or insufficient transparency about AI limitations.
AI hallucinations in financial advice or market analysis can significantly impact financial decisions, market confidence, and investor trust.The Air Canada case, where the company was held responsible for misinformation provided by its AI chatbot, sets an important precedent regarding corporate liability for AI hallucinations, particularly in customer-facing interactions. It implies that businesses cannot simply deploy AI agents and then disclaim responsibility for their outputs by arguing they are autonomous or experimental. Courts and regulatory bodies may increasingly view AI chatbots and similar systems as extensions of the company’s official communication channels. If an AI system provides incorrect information upon which a customer reasonably relies to their detriment, the company could be held liable, much as if a human employee had made the same error. This has profound legal and financial implications for businesses deploying AI, necessitating rigorous pre-deployment testing, clear (though potentially legally insufficient on their own) disclaimers, robust mechanisms for human override and error correction, and careful consideration of which tasks are appropriate to delegate to AI versus those that require definitive human judgment and accountability.
3.1.5. Cybersecurity: Overlooked Threats, False Alarms, and System Vulnerabilities
In the cybersecurity domain, AI hallucinations can introduce serious new risks, including overlooked threats or fabricated alerts.. AI tools used for threat detection might overlook genuine threats (false negatives) if their training data was biased or incomplete, or if the threat presents in a novel way not anticipated by the model.24 Conversely, AI systems can generate false alarms (false positives), fabricating threats or incorrectly identifying vulnerabilities that do not exist.24 This not only wastes valuable security analysts’ time and resources but also erodes trust in the AI tool, potentially leading to “alert fatigue” where genuine alerts might be ignored. Furthermore, if an AI provides inaccurate recommendations during an ongoing security incident, it can prolong the detection or recovery process, allowing threat actors more time to inflict damage.24
A particularly concerning risk is the potential for AI to mislead software developers into deploying code that inadvertently compromises system security.9 If an AI code generation assistant hallucinates a piece of code that appears functional but contains subtle security flaws (e.g., improper input sanitization, use of deprecated and insecure libraries, or logical errors that could be exploited), a developer—especially one under pressure or less experienced in security best practices—might incorporate this flawed code into a production system. This is akin to an unintentional, AI-assisted introduction of a backdoor or vulnerability. Adversarial attacks can also deliberately induce hallucinations in AI systems; for example, subtle modifications to an image, imperceptible to humans, have been shown to cause AI vision systems to grossly misclassify objects (e.g., identifying a cat as “guacamole”).11 If such attacks target AI systems used in security (e.g., facial recognition for access control, malware detection), they could bypass defenses.
The dual risk in cybersecurity—AI missing real threats and AI fabricating false ones—creates a challenging operational dilemma for security teams. It can lead to a “damned if you do, damned if you don’t” scenario, making it difficult for security personnel to confidently rely on AI security tools and effectively integrate them into their workflows. This underscores the need for AI cybersecurity tools to achieve exceptionally high levels of precision and recall, coupled with transparent reasoning for their alerts and detections, to be truly effective and trustworthy partners in defending against cyber threats. AI hallucinations waste valuable time and erode trust in a tool’s reliability.
Table 4 provides a compendium of these case studies, illustrating the breadth of real-world impacts.
Table 4: Compendium of Case Studies on AI Hallucinations: Domain, Specific Incident, Negative Impact, and Ethical Issues Raised.
Domain | Specific Incident | Documented Negative Impact(s) | Key Ethical Issues Raised | Key Sources |
Healthcare | Tessa AI chatbot giving harmful advice to users with eating disorders. | Potential direct harm to vulnerable users; service shutdown. | Patient safety, duty of care, undue influence on vulnerable individuals, responsible AI deployment in mental health. | 9 |
ChatGPT generating fabricated medical references (47% fabricated in one study). | Spread of medical misinformation; risk to research integrity and clinical decision-making if relied upon. | Accuracy in medical information, academic integrity, potential for indirect patient harm. | 5 | |
Law | NY lawyer fined for ChatGPT fabricating six non-existent legal case citations. | Legal sanctions against the lawyer; wasted court resources; damage to professional reputation. | Professional responsibility, due diligence, integrity of the justice system, competence in using legal tech. | 10 |
Morgan & Morgan attorneys submitting AI-generated fake precedents vs. Walmart. | Potential for miscarriage of justice if undetected; reputational damage to the firm; internal warnings issued. | Ethical use of AI in legal practice, verification of AI-generated content, accountability for submissions to court. | 10 | |
Journalism/ Information | AI-driven robocalls impersonating Joe Biden in NH primary. | Attempted voter dissuasion; manipulation of democratic processes; spread of political disinformation. | Integrity of elections, responsible use of voice synthesis AI, combating deepfakes and misinformation. | 29 |
Finance/ Business | Google’s Bard AI error about James Webb Telescope discovery. | Reported $100 billion loss in Alphabet Inc.’s market value; reputational damage. | Corporate accountability for AI statements, market trust in AI capabilities, transparency about AI limitations. | 9 |
Air Canada chatbot hallucinating incorrect refund policies. | Company forced to honor incorrect policy; financial liability; damage to customer trust and brand reputation. | Consumer rights, corporate liability for AI agent actions, clarity in AI-customer interactions. | 25 | |
Cybersecurity | AI tools overlooking threats or creating false alarms. | Potential for successful cyberattacks if threats are missed; wasted resources on false alarms; erosion of analyst trust. | Reliability of AI in critical security functions, balancing automation with human expertise, preventing alert fatigue. | 24 |
AI misleading developers into deploying vulnerable code. | Introduction of security flaws into systems; potential for exploitation by malicious actors. | Secure software development practices with AI, developer responsibility, preventing AI-assisted vulnerability creation. | 9 |
3.2. Ethical Implications in High-Stakes Environments
Beyond the immediate, documented impacts of specific incidents, the phenomenon of AI hallucination raises profound and far-reaching ethical questions, particularly when these systems are deployed in environments where decisions have significant consequences for individuals and society. These ethical implications touch upon fundamental values such as trust, truth, fairness, and accountability.
3.2.1. Erosion of Trust and Public Confidence in AI Systems
Trust is a cornerstone for the successful and beneficial integration of AI technologies into society. AI hallucinations, by their very nature—disseminating erroneous, misleading, or fabricated information often with an air of confidence—directly attack this foundation.25 When users encounter AI systems that provide unreliable or false information, especially in critical situations such as seeking medical advice or financial guidance, their confidence in those systems, and potentially in AI technology as a whole, is undermined.6 Repeated errors or high-profile failures can lead to a significant reduction in user willingness to adopt or rely on AI tools, even for tasks where they might otherwise be beneficial.24 While research suggests that providing users with the ability to correct AI mistakes can positively influence their trust and even spark curiosity about the AI’s functioning 32, the initial damage from a significant hallucination can be difficult to repair.
This erosion of trust is not necessarily confined to the specific AI application that produced the hallucination. Due to the often-undifferentiated public perception of “AI,” failures in one prominent AI system can cast a shadow over the entire field, leading to a “contagion of distrust.” High-profile incidents of AI hallucination in sensitive domains like healthcare or law can foster a general public sentiment that AI is inherently unreliable or deceptive. This generalized skepticism can then act as a barrier to the adoption of genuinely useful, well-vetted, and reliable AI tools in other areas, such as scientific research, environmental monitoring, or accessibility services, thereby hindering progress and the realization of AI’s potential benefits. The AI community, therefore, bears a collective responsibility to address the problem of hallucinations, as failures in one segment can negatively impact the perception and acceptance of the entire technological domain.
Furthermore, rebuilding trust once it has been significantly damaged by AI hallucinations is a far more arduous task than establishing trust in the first place. Negative experiences often have a more lasting impact on perception than positive ones. A user who has been seriously misled by an AI hallucination—for instance, by receiving dangerously incorrect medical advice or suffering financial loss due to flawed AI-generated information—is likely to be extremely wary of trusting AI systems again, even if those systems are subsequently improved or if different, more reliable AI tools are offered. This underscores the critical importance of adopting a “trust by design” or “safety by design” approach from the very outset of AI development and deployment. This involves not only technical rigor in testing and validation but also transparency about limitations, clear mechanisms for error reporting and redress, and unambiguous lines of accountability. Attempting to remediate trust after significant erosion is a far more challenging and costly endeavor than proactively building and maintaining it.
3.2.2. The Amplification of Misinformation, Disinformation, and Societal Harm
AI’s capacity to generate plausible, coherent, and often confidently delivered falsehoods makes it a powerful engine for the amplification of misinformation and, when used with malicious intent, disinformation.25 Hallucinated content, especially when disseminated rapidly through digital platforms, can aggravate existing misinformation problems, leading to poor decision-making by individuals and groups, and potentially dangerous behavior, particularly during crises or periods of social instability.25 AI systems can be exploited to seed or lend credence to conspiracy theories, distort public discourse on sensitive issues, and generate content that harms the reputations of individuals or organizations.28 The historical example of the Piltdown Hoax, where deliberately fabricated “evidence” misled the scientific community for decades due to its convincing presentation, serves as a sobering reminder of how effectively plausible falsehoods can take root.27 AI hallucinations, with their veneer of technological authority, can make such misinformation even more potent.
The potential for AI hallucinations to be weaponized for targeted disinformation campaigns represents a significant threat to democratic processes and social cohesion. Generative AI allows for the rapid creation and customization of content at an unprecedented scale. Malicious actors can leverage AI’s ability to hallucinate (or be deliberately prompted to produce falsehoods that align with a particular narrative) to create highly personalized and convincing false narratives designed to exploit existing biases, sow discord, or manipulate public opinion, for instance, during election cycles.29 The inherent plausibility of AI-generated text, images, or videos makes these campaigns more difficult to detect and counter than traditional forms of “fake news.”
Moreover, the “authority” that is often implicitly attributed to AI-generated content can make hallucinated misinformation particularly effective in shaping beliefs, especially among individuals who are less familiar with AI’s fallibility or who lack strong critical evaluation skills.27 If an AI system confidently asserts a piece of (hallucinated) misinformation, users who perceive AI as inherently objective or super-intelligent might accept it as truth without question. This effect is compounded if the AI is integrated into platforms or services that users already trust. This necessitates a multi-pronged response: developing sophisticated AI-based tools for detecting AI-generated disinformation, significantly enhancing public digital and media literacy programs to foster critical thinking about online content, and exploring regulatory frameworks to address the malicious creation and dissemination of harmful AI-generated disinformation while safeguarding freedom of expression.
3.2.3. Perpetuation and Amplification of Bias and Discriminatory Outcomes
AI models learn from the data they are trained on. If this data reflects existing societal biases related to race, gender, age, socioeconomic status, or other characteristics, the models can internalize these biases. Hallucinations can then become a vehicle for perpetuating and even amplifying these biases, leading to discriminatory outcomes in critical areas such as hiring, loan applications, criminal justice, and access to services.25 For example, an AI model trained on historically biased hiring data might “hallucinate” negative attributes or predict lower success rates for candidates from underrepresented groups, even if their qualifications are equivalent or superior. This can result in the creation or reinforcement of inaccurate narratives that disproportionately harm certain demographics and solidify existing structural inequities.28
A particularly insidious aspect of this problem is the potential for “feedback loops of bias.” If an AI system, due to initial biases in its training data, makes discriminatory decisions (e.g., unfairly denying loans to individuals from a particular neighborhood, or flagging individuals from a certain ethnic group for higher scrutiny in security contexts), these decisions, if not carefully audited and corrected, might be recorded as outcomes. If this outcome data is then used to retrain or update the AI model, the initial bias can be further entrenched and amplified. The model learns that its biased predictions were “correct” according to the data it was fed, making it even more likely to produce similar discriminatory (and potentially hallucinated) outputs in the future. This makes the bias increasingly difficult to detect and eradicate over time. Continuous auditing for biased outcomes, careful curation of retraining data, and the development of fairness-aware machine learning techniques are essential to break these cycles.
Furthermore, the intersection of AI hallucination and bias can lead to particularly pernicious forms of harm where the AI generates seemingly “objective” or plausible but false justifications for discriminatory actions, thereby masking the underlying bias. For instance, a biased AI model might deny a loan application from a member of a protected group. When prompted to explain its decision (a capability often sought for transparency), the AI might not explicitly state the biased reason (e.g., “denied because of demographic group X”). Instead, it could hallucinate a set of superficially neutral but factually incorrect or irrelevant “reasons” that appear to justify the discriminatory outcome (e.g., fabricating non-existent negative financial indicators in the applicant’s actual record, or misinterpreting valid data in a negative light). This makes the bias much harder to identify and challenge because the stated reasons, though false, may seem legitimate on the surface. This highlights the critical need for explainability methods (XAI) that can reveal the true drivers of AI decisions, rather than merely generating post-hoc rationalizations which themselves can be products of hallucination. It also underscores the importance of scrutinizing not just the AI’s decision but also the veracity and relevance of its purported “reasoning.”
3.2.4. Challenges in Accountability, Liability, and the “Black Box” Dilemma
When AI hallucinations cause harm—be it financial loss, reputational damage, compromised patient safety, or a miscarriage of justice—the question of who is responsible becomes paramount. However, determining accountability and liability for AI hallucinations is fraught with challenges.9 Generative AI models, particularly large LLMs, often operate as “black boxes”; their internal decision-making processes are exceedingly complex and opaque, making it difficult to trace exactly why a particular hallucination occurred or to assign responsibility in a straightforward manner.9 The probabilistic nature of their outputs means that responses are not always fully deterministic, further complicating efforts to pinpoint specific points of failure.
AI development companies may argue that hallucinations are an inherent limitation of current generative AI technology, attempting to shift the burden of verification onto users or deployers of the systems.9 However, as AI becomes more deeply integrated into critical decision-making processes, this stance is increasingly untenable. A “shared responsibility” model is beginning to emerge, suggesting that liability for harms caused by AI hallucinations might be distributed among various actors, including the developers who create the AI models, the organizations that deploy them in specific applications, and potentially even the users who interact with them, based on factors such as the degree of control each party had, the foreseeability of the harm, and evidence of negligence.9 The EU AI Act, for example, classifies AI systems by risk level and imposes more stringent requirements, including those related to accuracy and robustness, for high-risk applications such as those in legal and healthcare systems.9
The “black box” nature of many advanced AI models not only complicates legal accountability but also hinders the ability to effectively learn from errors and prevent future hallucinations. If developers cannot precisely understand why a specific hallucination occurred—which specific data artifacts, architectural quirks, or training dynamics contributed to it—then efforts to fix the root cause may be superficial or ineffective. This makes targeted debugging and model improvement significantly more challenging. Consequently, research into interpretable AI and eXplainable AI (XAI) is not merely an academic pursuit or a means to enhance user trust; it is also crucial for enabling developers to build more robust, reliable, and less hallucination-prone systems. Without better insight into the “why” behind AI behaviors, including erroneous ones, mitigation efforts may remain reactive and incomplete.
Implementing a shared responsibility model in practice is also complex and carries the risk of disproportionately burdening less sophisticated users or those with less power and fewer resources within the AI ecosystem. While AI developers possess deep technical knowledge and control over the model’s design, end-users often have very limited understanding of AI’s inner workings and its potential for error. Expecting an average individual to effectively verify complex AI-generated outputs (e.g., a nuanced medical diagnosis or a detailed financial projection) or to bear significant responsibility for harms caused by hallucinations they could not reasonably have detected may be unrealistic and unfair. Organizations that deploy AI systems (e.g., hospitals using AI for diagnostics, companies using AI for customer service) are in an intermediate position but may also lack full transparency from the original model developers. Therefore, clear guidelines, industry standards, and potentially specific regulations are needed to define the respective responsibilities of each party in a fair, equitable, and practical manner. This includes establishing what constitutes “due diligence” for users, what transparency and safety obligations developers must meet, and what oversight and risk management responsibilities deployers must undertake. Without such clarity, there is a significant risk that liability could be unfairly shifted towards the most vulnerable parties in the AI value chain.
4. Conclusion: Navigating Towards Trustworthy and Responsible AI
The pervasive challenge of AI hallucinations, with its multifaceted technical origins and significant real-world consequences, demands a concerted and proactive response from the global AI community. Addressing this phenomenon is not merely a technical refinement but a fundamental imperative for building AI systems that are reliable, ethical, and ultimately trustworthy.
4.1. The Imperative of Addressing Hallucinations for Building Reliable and Ethical AI
The preceding sections have detailed how AI hallucinations—plausible but false or misleading outputs—can undermine the very purpose for which AI systems are often created: to provide accurate information, augment human capabilities, and improve decision-making. The documented impacts in critical sectors like healthcare, law, finance, and the information ecosystem demonstrate that hallucinations are not benign quirks but can lead to tangible harm, erode public confidence, and exacerbate societal inequities.9 Therefore, understanding and actively mitigating hallucinations is an essential prerequisite for the development and deployment of trustworthy AI.6 An AI system that frequently generates baseless or incorrect information cannot be considered reliable, and if such information leads to harmful outcomes, its deployment cannot be considered ethical. Mitigating these errors is thus an ethical responsibility for developers, deployers, and policymakers.28
The pursuit of “hallucination-resilient AI” 28 is intrinsically linked to the broader objectives of AI safety and AI ethics. A model’s propensity to hallucinate can be viewed as a key indicator of its overall reliability and its alignment with human values and expectations. An AI that fabricates legal precedents, offers incorrect medical advice, or generates biased content is, by definition, unsafe and unethical in those contexts. Therefore, efforts to reduce hallucinations—through improved data governance, more robust model architectures, better training paradigms, and rigorous validation—are not isolated technical fixes but integral components of a comprehensive strategy to ensure AI systems are beneficial and operate within acceptable societal norms. Success in minimizing hallucinations will directly contribute to making AI systems safer, more dependable, and more aligned with the principles of responsible technology.
The observation that human expert advice can significantly mitigate the negative impacts of AI hallucinations, by reducing users’ cognitive load and alleviating negative emotions when faced with incorrect AI outputs 6, points towards a crucial direction for the future. Given that completely eradicating hallucinations from complex generative models is a formidable challenge with current technologies 6, the most robust and trustworthy AI applications, particularly in critical domains, are likely to be those that foster synergistic human-AI collaboration. In such a paradigm, AI systems augment human capabilities by processing vast amounts of information and generating initial hypotheses or drafts, while human experts provide critical oversight, verification, contextual understanding, and ethical judgment. The AI assists the human, and the human guides, corrects, and ultimately remains accountable for the final decision or output. This vision moves away from a purely automation-focused perspective of AI towards one that emphasizes partnership and mutual reinforcement of strengths.
Many current mitigation techniques function as patches against AI hallucinations rather than permanent solutions, highlighting the need for foundational changes.
4.2. Proactive Intervention: Shaping the Future of Human-AI Collaboration, Public Trust, and Responsible Innovation
A reactive approach to AI hallucinations—waiting for failures to occur and then attempting to patch them—is insufficient given the potential for rapid and widespread harm. Proactive intervention throughout the AI lifecycle is essential to shape a future where human-AI collaboration can flourish, public trust in AI is earned and maintained, and innovation proceeds responsibly.34 This proactive stance involves a commitment to transparency about AI capabilities and limitations, responsible implementation practices that prioritize safety and ethical considerations, and the establishment of robust governance frameworks to oversee AI development and deployment.34 Key proactive measures include continuous monitoring of AI system performance, rigorous auditing of training data for biases and inaccuracies, the active involvement of diverse stakeholders (including domain experts and representatives of affected communities) in the design and oversight of AI applications, and building systems that are designed for continuous improvement and adaptation.34
“Responsible innovation” in the context of AI means anticipating potential risks, such as the generation of harmful hallucinations, and embedding mitigation strategies into the design and development process before systems are widely deployed, rather than primarily addressing harm after it has occurred.34 This requires a cultural shift within parts of the AI development community, moving away from a mindset that might prioritize rapid capability scaling above all else, towards one that places a co-equal emphasis on safety, reliability, and ethical alignment. The history of technological development is replete with examples where unbridled innovation without adequate foresight led to negative consequences that required difficult, costly, and sometimes incomplete remediation later on. With AI, particularly powerful generative models prone to hallucination, the potential for swift and extensive harm—through the spread of misinformation, the erosion of trust in institutions, or the perpetuation of systemic biases—is too significant to ignore. Responsible innovation in AI therefore demands a pre-emptive and sustained focus on building systems that are not only intelligent but also intelligible, dependable, and aligned with human values.
Fostering public trust through such proactive interventions is not merely about mitigating the negative aspects of AI hallucinations; it is fundamentally about unlocking the immense positive potential of human-AI collaboration. Trust is the currency of effective collaboration. If individuals and institutions cannot rely on the information provided by AI systems due to a pervasive fear of encountering hallucinations, they will naturally be hesitant to integrate these tools into their workflows, delegate meaningful tasks to them, or build new processes around them. By proactively working to minimize hallucinations, by being transparent about AI’s current capabilities and inherent limitations, and by establishing clear avenues for redress when errors occur, we can create an environment where users feel more confident and secure in interacting with AI. This confidence is essential for enabling humans to explore AI’s potential as a powerful partner in discovery, creativity, and problem-solving, rather than viewing it solely as an unpredictable tool that requires constant, wary supervision. Investing in making AI more trustworthy by tackling the challenge of hallucinations is, therefore, an investment in its ultimate utility and its capacity to positively augment human capabilities across countless domains. It is about enabling a more productive, equitable, and beneficial future for human-AI interaction.
5. Recommendations for Mitigation and Responsible Development
Addressing the challenge of AI hallucinations requires a multi-stakeholder approach involving concerted efforts from researchers, developers, policymakers, and end-users. Based on the comprehensive examination of AI hallucinations, their causes, consequences, and current mitigation strategies, the following recommendations are proposed to foster more reliable, trustworthy, and responsibly developed AI systems:
For Researchers:
- Advance Fundamental Research: Prioritize research into novel AI architectures and training paradigms that are inherently less prone to hallucination. This includes exploring areas such as causal AI (to imbue models with a better understanding of cause-and-effect relationships), neuro-symbolic methods (to combine the strengths of deep learning with explicit reasoning), improved grounding techniques (to better connect model representations to real-world entities and facts), and mechanisms for more robust knowledge representation and reasoning.
- Develop Sophisticated Evaluation Metrics and Benchmarks: Create and standardize more robust, nuanced, and comprehensive benchmarks and metrics for evaluating hallucinations across all modalities (text, image, video, multimodal). These evaluations should aim to correlate strongly with human perception of accuracy, coherence, and trustworthiness, and should be designed to probe for a wide variety of hallucination types, including subtle and context-dependent errors.
- Investigate Reliable Uncertainty Quantification: Focus on developing and integrating methods that allow AI models to reliably assess and express the uncertainty or confidence associated with their outputs. Models should be incentivized to indicate when they “don’t know” or when their confidence is low, rather than defaulting to a plausible but potentially incorrect answer. Calibration of these uncertainty estimates is also crucial.
For Developers and AI Providers:
- Prioritize Data Governance and Quality: Implement rigorous processes for data collection, curation, cleaning, and labeling, with a strong emphasis on maximizing accuracy, diversity, and representativeness, while actively working to identify and mitigate biases throughout the AI development lifecycle. Regularly update training datasets to maintain currency.
- Implement Comprehensive Testing and Validation: Establish robust and continuous testing and validation pipelines specifically designed to detect and measure hallucinations. This should include adversarial testing, out-of-distribution testing, and evaluation across diverse demographic groups and use cases.
- Integrate Interpretability and Explainability (XAI): Design models and systems with XAI features that can help developers and users understand the reasoning behind AI outputs, making it easier to identify, debug, and learn from instances of hallucination.
- Adopt “Safety by Design” and “Ethics by Design” Principles: Embed considerations of hallucination risk, safety, and ethical implications into the AI design and development process from the very beginning, rather than treating them as afterthoughts. Conduct thorough risk assessments for potential harms from hallucinations in specific applications.
- Ensure Transparency and Clear Communication: Provide users with clear, accessible, and honest documentation regarding the capabilities and limitations of AI models, including their known propensity to hallucinate. Clearly label AI-generated content and avoid overstating model abilities.
- Develop Robust Feedback Mechanisms: Implement systems that allow users to easily report hallucinations and other errors. Use this feedback actively to improve model performance and safety.
For Policymakers and Regulatory Bodies:
- Establish Risk-Based Regulatory Frameworks: Consider developing adaptive, risk-based regulatory frameworks for AI systems, similar in principle to the EU AI Act 9, that impose stricter requirements (e.g., for accuracy, robustness, transparency, human oversight) on high-risk AI applications where hallucinations could cause significant harm (e.g., healthcare, law, critical infrastructure).
- Promote Standards for Transparency and Accountability: Encourage or mandate standards for transparency in AI systems, including clear disclosure when users are interacting with an AI, information about the data used to train models (where feasible and appropriate), and known limitations. Develop frameworks for establishing accountability when AI hallucinations lead to harm.
- Support Research and Development of Trustworthy AI: Invest in and incentivize research and development initiatives focused on creating more reliable, interpretable, and hallucination-resistant AI technologies.
- Foster Public Education and AI Literacy: Support and promote public education programs aimed at increasing AI literacy among citizens. This includes helping people understand how AI systems work, their potential benefits and risks (including hallucinations), and how to critically evaluate AI-generated content.
For Users and Organizations Deploying AI:
- Cultivate Critical AI Literacy and Skepticism: Understand that current AI systems, especially generative models, can and do make mistakes and can present false information with apparent confidence. Approach AI-generated content with a healthy degree of skepticism.
- Implement Human Oversight and Verification: Do not blindly trust AI outputs, particularly in high-stakes decision-making contexts. Establish robust human oversight and verification processes to check the accuracy and appropriateness of AI-generated information before relying on it.
- Employ Effective Prompt Engineering: When interacting with generative AI, use clear, specific, and contextual prompts. Experiment with different prompting strategies to guide the AI towards more accurate and relevant responses. Provide negative constraints where appropriate (e.g., “do not invent information”).
- Actively Report Errors: When encountering hallucinations or other errors, report them to the AI developers or service providers. This feedback is crucial for model improvement.
- Assess Appropriateness for Task: Carefully evaluate whether current generative AI tools are appropriate for tasks that demand high levels of factual accuracy and reliability, especially if robust verification mechanisms are not in place. Consider the potential consequences of hallucinations in the specific use case.
- Demand Transparency and Accountability: Advocate for greater transparency from AI providers regarding model capabilities, limitations, and data sources. Seek clarity on accountability mechanisms if AI systems cause harm.
By adopting these multi-faceted recommendations, the global community can work collaboratively towards mitigating the risks associated with AI hallucinations, thereby fostering an ecosystem where AI technology can be developed and deployed in a manner that is not only innovative but also safe, ethical, and deserving of public trust. Addressing hallucinations is a continuous journey, requiring ongoing vigilance, research, and adaptation as AI technology continues to evolve.
Works cited
- What are AI Hallucinations? – K2view, accessed on May 10, 2025, https://www.k2view.com/what-are-ai-hallucinations/#:~:text=According%20to%20Microsoft%20Bing%2C%20AI,misleading%20information%20presented%20as%20fact.
- What are AI hallucinations? | Google Cloud, accessed on May 10, 2025, https://cloud.google.com/discover/what-are-ai-hallucinations
- AI Hallucinations: A Guide With Examples – DataCamp, accessed on May 10, 2025, https://www.datacamp.com/blog/ai-hallucination
- “Garbage In, Garbage Out”: How to Stop Your AI from Hallucinating, accessed on May 10, 2025, https://shelf.io/blog/garbage-in-garbage-out-ai-implementation/
- What are AI hallucinations & how to mitigate them in LLMs | KNIME, accessed on May 10, 2025, https://www.knime.com/blog/ai-hallucinations
- Full article: AI Hallucination in Crisis Self-Rescue Scenarios: The …, accessed on May 10, 2025, https://www.tandfonline.com/doi/full/10.1080/10447318.2025.2483858?src=
- Hallucinations in AI Models -A Quick Guide – BigOhTech, accessed on May 10, 2025, https://bigohtech.com/hallucinations-in-ai-models-a-quick-guide
- What are AI Hallucinations? – K2view, accessed on May 10, 2025, https://www.k2view.com/what-are-ai-hallucinations/
- AI HALLUCINATIONS: WHEN CREATION COMES AT A COST …, accessed on May 10, 2025, https://chambers.com/articles/ai-hallucinations-when-creation-comes-at-a-cost-who-pays
- AI HALLUCINATIIONS IN LEGAL FILING: A CRISIS IN THE MAKING …, accessed on May 10, 2025, https://justai.in/ai-hallucinatiions-in-legal-filing-a-crisis-in-the-making/
- Understanding and Mitigating AI Hallucination – DigitalOcean, accessed on May 10, 2025, https://www.digitalocean.com/resources/articles/ai-hallucination
- aclanthology.org, accessed on May 10, 2025, https://aclanthology.org/2025.trustnlp-main.15.pdf
- Exploring the Evolution of Physics Cognition in Video Generation: A Survey – arXiv, accessed on May 10, 2025, https://arxiv.org/html/2503.21765v1
- Improving Dynamic Object Interactions in Text-to-Video Generation with AI Feedback – arXiv, accessed on May 10, 2025, https://arxiv.org/abs/2412.02617
- (PDF) ViBe: A Text-to-Video Benchmark for Evaluating Hallucination …, accessed on May 10, 2025, https://www.researchgate.net/publication/385919993_ViBe_A_Text-to-Video_Benchmark_for_Evaluating_Hallucination_in_Large_Multimodal_Models
- VidCapBench: A Comprehensive Benchmark of Video Captioning for Controllable Text-to-Video Generation – Semantic Scholar, accessed on May 10, 2025, https://www.semanticscholar.org/paper/VidCapBench%3A-A-Comprehensive-Benchmark-of-Video-for-Chen-Zhang/f42f6fd6414a1aa16cf3827ca184281d001d06b6
- Hallucination of Multimodal Large Language Models: A Survey – arXiv, accessed on May 10, 2025, https://arxiv.org/html/2404.18930v2
- arxiv.org, accessed on May 10, 2025, https://arxiv.org/pdf/2404.18930
- Survey of Hallucinations in Multimodal Models – Galileo AI, accessed on May 10, 2025, https://www.galileo.ai/blog/survey-of-hallucinations-in-multimodal-models
- AI Hallucinations & DeepFake Videos – Finding Reliable Information – DSC Library, accessed on May 10, 2025, https://library.daytonastate.edu/reliable/ai
- SynArtifact: Classifying and Alleviating Artifacts in Synthetic Images via Vision-Language Model – arXiv, accessed on May 10, 2025, https://arxiv.org/html/2402.18068v2
- The Curse of Multi-Modalities: Evaluating Hallucinations of Large Multimodal Models across Language, Visual, and Audio – Paper Details – ChatPaper – AI, accessed on May 10, 2025, https://www.chatpaper.ai/dashboard/paper/06ae4127-8b92-4d46-96c8-0da4806cdd60
- AI Hallucinations: What They Are and 5 Hacks to Avoid Them …, accessed on May 10, 2025, https://yourgpt.ai/blog/general/ai-hallucinations-and-ways-to-avoid
- AI hallucinations can pose a risk to your cybersecurity | IBM, accessed on May 10, 2025, https://www.ibm.com/think/insights/ai-hallucinations-pose-risk-cybersecurity
- What are AI Hallucinations & How to Prevent Them? [2025] | Enkrypt AI, accessed on May 10, 2025, https://www.enkryptai.com/blog/how-to-prevent-ai-hallucinations
- Medical Hallucination in Foundation Models and Their Impact on Healthcare – medRxiv, accessed on May 10, 2025, https://www.medrxiv.org/content/10.1101/2025.02.28.25323115v1.full-text
- AI’s Dark Side: The Emergence of Hallucinations in the Digital Age …, accessed on May 10, 2025, https://www.infosecurity-magazine.com/opinions/ai-dark-side-hallucinations/
- (PDF) Towards Hallucination-Resilient AI: Navigating Challenges …, accessed on May 10, 2025, https://www.researchgate.net/publication/385893920_Towards_Hallucination-Resilient_AI_Navigating_Challenges_Ethical_Dilemmas_and_Mitigation_Strategies
- digitalcommons.lindenwood.edu, accessed on May 10, 2025, https://digitalcommons.lindenwood.edu/cgi/viewcontent.cgi?article=1738&context=faculty-research-papers
- AI Strategies Series: 7 Ways to Overcome Hallucinations, accessed on May 10, 2025, https://insight.factset.com/ai-strategies-series-7-ways-to-overcome-hallucinations
- (PDF) Assessing the ability of GPT-4o to visually recognize medications and provide patient education – ResearchGate, accessed on May 10, 2025, https://www.researchgate.net/publication/385553820_Assessing_the_ability_of_GPT-4o_to_visually_recognize_medications_and_provide_patient_education
- AI Hallucination in Crisis Self-Rescue Scenarios: The Impact on AI …, accessed on May 10, 2025, https://www.researchgate.net/publication/390738921_AI_Hallucination_in_Crisis_Self-Rescue_Scenarios_The_Impact_on_AI_Service_Evaluation_and_the_Mitigating_Effect_of_Human_Expert_Advice
- What Can I Help You with Today? Minimizing Legal Risks of AI-Powered Chatbots, accessed on May 10, 2025, https://www.harrisbeachmurtha.com/insights/minimizing-legal-risks-of-ai-powered-chatbots/
- Public Trust in the Age of Artificial Intelligence – Police Chief Magazine, accessed on May 10, 2025, https://www.policechiefmagazine.org/balancing-innovation-responsibility-ai-outreach/
These models are designed for tasks like image captioning or visual question answering but often produce outputs that are inconsistent with visual input.
Types of Multimodal Hallucinations
Modality | Hallucination Type | Detailed Manifestation | Example |
---|---|---|---|
MLLMs / LVLMs | Category Hallucination | Describes object categories that are not in the image | “Benches and a fence” in a park image where none exist |
MLLMs / LVLMs | Attribute Hallucination | Misattributes color, shape, material, etc. | “Pink blossoms” when they are white |
MLLMs / LVLMs | Relation Hallucination | Misrepresents relationships between objects | Claims people are “standing around a girl” without visual basis |
Text-to-Image | Visual Artifact | Distorted features | Six fingers on one hand |
Text-to-Video | Physical Incongruity | Violations of physics, odd deformations, or temporal inconsistency | Objects vanish or deform unnaturally |
Core Technical Drivers of Hallucinations
Hallucinations are rooted in identifiable issues such as poor data quality, flawed model architectures, and inadequate inference strategies.
Key Technical Causes
Causal Category | Specific Factor | Description |
---|---|---|
Data-Related | Inaccurate/Noisy Data | Incorrect or irrelevant training data leads to flawed output |
Data-Related | Biased Data | Societal biases reflected in training data lead to discriminatory outputs |
Model-Related | Overfitting | Model memorizes training examples and fails to generalize |
Inference/Grounding | Probabilistic Generation | Predicts plausible sequences, not necessarily factual ones |
Inference/Grounding | Decoding Strategies | Randomness in sampling can increase hallucination risk |
Mitigation Strategies
Multiple mitigation strategies exist, each with benefits and limitations. These include improved data curation, prompt engineering, RAG, RLHF, and human oversight.
Overview of Strategies
Strategy | Description | Effectiveness | Limitations |
---|---|---|---|
Enhanced Data Quality | Clean, diverse, and updated datasets | High | Hard to maintain at scale |
Prompt Engineering | Use of clear and structured prompts | Medium | Requires expertise |
RAG | Retrieves facts before generation | High | Relies on quality of source data |
Human Oversight | Manual verification of outputs | Very High | Resource-intensive |
Real-World Consequences
Hallucinations in high-risk domains like healthcare, law, finance, and cybersecurity can have significant consequences.
Case Studies
Domain | Incident | Negative Impact | Ethical Issues |
---|---|---|---|
Healthcare | “Tessa” chatbot giving harmful advice | User harm, service shutdown | Patient safety, responsibility |
Law | Faked legal citations | Legal sanctions, loss of trust | Due diligence, misuse of AI |
Finance | Bard AI error on telescope discovery | $100B market loss | Corporate responsibility |
Cybersecurity | AI-generated false threat alerts | Wasted resources, ignored true threats | Reliability in critical systems |