When people ask about “lying” or “avoidant” neurons in LLMs, it’s important to realize that these models don’t have a specific “liar” component … It’s more about how the model processes and predicts information. Imagine you’re reading a CAPTCHA … sometimes the letters and numbers are hard to distinguish because of how they’re distorted. Your brain has to make a guess. You might misread a “5” for an “S,” or a “0” for an “O.” That’s similar to how LLMs generate text.
The model doesn’t decide to lie … it simply looks at the patterns it’s seen during training and produces what seems most likely. Sometimes, due to the ambiguity of the prompt or the data it was trained on, it can generate misleading or incorrect answers. This happens because the model is sampling from possible continuations, not based on truth but on probability. It’s like guessing a distorted letter in a CAPTCHA … what’s likely, not necessarily correct.
So, no, there’s no “lying” neuron. But, like reading a CAPTCHA, there are moments of uncertainty where the model can misinterpret or generate an answer that’s wrong. The behavior we see, like avoidance or incorrect responses, is a result of this probabilistic reasoning, and it’s not from a single part of the model “deciding” to mislead. It’s the sum of many subtle decisions.
Additionally, it’s important to understand that two identical models could behave differently based on how they’re fine-tuned. For example, if you have Model A and Model B, both with the same architecture, but one is fine-tuned on medical data and the other on legal data, they will respond better to their respective topics. Model A would give more accurate responses on health-related queries, while Model B would perform better on legal matters. This fine-tuning shapes the model’s behavior and improves its performance for specific tasks or domains.
There are thousands of models available on platforms like Hugging Face and GitHub, each designed for different purposes—from sentiment analysis to image captioning and more. However, these models are often based on a handful of core architectures, like GPT, BERT, or T5. These base architectures are the starting point, and the variations you see are typically just fine-tuned versions for specific tasks. So, even though you might see hundreds of models out there, they often share the same foundational architecture, with only the training data or the fine-tuning process setting them apart for particular use cases.