Start with a prediction

Choose a layer and a unit. Look at its category responses, then inspect the individual words. Start with L12/U646, which strongly prefers animals. Find a unit that prefers plants and compare the two profiles.

The 20 original units were selected using a separate animal/tool vocabulary. The layer explorer also includes exploratory examples so you can visit every layer. Check the selection label before treating an example as part of the frozen set.

What you are seeing

These are saved measurements from a pretrained Gemma model. The controls choose which measurement to display. They do not run a new prompt, disable a neuron, or change the model’s answer. A strong category response is an observation to investigate, not proof that one unit stores a concept.

Read the experiment Open playground on its own Download evidence