Response properties and synaptic connections of mechanoafferent neurons in cerebral ganglion of Aplysia

The present report describes the properties of mechanoafferent neurons found in symmetrical clusters on the ventral surface of the cerebral ganglion. We have studied their response characteristics, axon distribution to peripheral nerves and interganglionic connectives, receptive-field organization, synaptic output to identified cell groups in the cerebral ganglion, and synaptic plasticity. The properties of the mechanoafferent neurons suggest that they may mediate a number of different reflex responses and behavioral modifications of these responses. The data are consistent with the observation that tactile stimuli applied to the head can elicit a variety of behaviors, including orientation, biting, and withdrawal.