click empty agar to drop food
click the worm's head or tail to poke it

Wind-Up Minds · 02The Worm

C. elegans has 302 neurons, and its whole wiring diagram has been mapped since the 1980s. This toy runs 21 of the real, named ones, using the same trick Eon Systems used for their fly: each neuron just adds up its inputs and fires when it crosses a threshold.

Nobody programmed "find food." When the smell gets weaker, ASER fires and AVA makes the worm back up and turn. When the smell gets stronger, AIY keeps AVB going forward. That's enough to find dinner.

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excitesinhibitsbrightness = firing rate

AVB forwardAVA backward

Honest label: this is a hand-wired sketch of the real chemotaxis and touch circuits (ASE, AIY/AIZ/AIB, ALM/AVM/PLM, AVA/AVB), not the full 302-neuron connectome. The synapses and weights are simplified so the behavior shows up. The full model lives at OpenWorm.