This phenomenon was recently discovered in the CNS of the pteropod mollusc, Clione limacina . A large group of putative motoneurons controlling prey capture reactions of the tentacle-like oral appendages has been identified in the cerebral ganglia of Clione .
All neurons are electrically coupled and normally silent.
Brief intracellular stimulation of an individual neuron can trigger synchronous afterdischarges of up to 30 s duration in the entire population of neurons. The functional role of afterdischarges is the spread and synchronization of spike activity among all neurons in the population and transformation of brief excitatory inputs into prolonged and stable motor responses. The results of this study indicate that afterdischarges result from excitatory chemical synaptic inputs produced by cerebral neurons which in turn can be activated by prey capture motoneurons, thus organizing positive feedback. Electrotonic coupling may also contribute to recruitment and synchronization of neuron firing during afterdischarges.