Further Studies of Crayfish Escape Behaviour Ii. Giant Axon-mediated Neural Activity in the Appendages

Stereotyped responses were evoked in a number of motoneurones in the appendages of semi-intact crayfish when the command neurones for escape behaviour were activated. The medial giant neurones mediated short latency responses in pereiopod common inhibitor, promotor and extensor motoneurones, several abdominal first root neurones and one uropod exopodite promotor motoneurone. The lateral giant neurones mediated short latency responses in the pereiopod common inhibitor neurones, the same abdominal first root neurones and one uropod protopodite promotor motoneurone. These responses can be correlated with stereotyped movements of the appendages which occur in the normal escape behaviour of crayfish.