C. elegans Touch-Withdrawal Neural Circuit

The gentle-touch escape response is one of the best-characterized circuits in the entire C. elegans connectome: a handful of mechanosensory neurons (ALML, ALMR, AVM at the head; PLML, PLMR at the tail) feed into two small groups of command interneurons — AVD/AVA driving backward locomotion, PVC/AVB driving forward locomotion — that in turn set the direction of the dorsoventral body-wall muscle contraction wave. This simulation runs each neuron as a leaky integrate-and-fire unit wired with the real synaptic topology of that circuit, so touching the virtual worm's head or tail triggers an actual spike cascade — sensory neurons fire, command interneurons integrate and fire in turn, and the resulting backward/forward drive imbalance propagates a visible contraction wave along a modeled worm body, exactly mirroring how a real nematode reverses away from a touch at the head or accelerates forward from a touch at the tail.