The effect of the time pattern of presynaptic impulses on the transfer of information across an inhibitory synapse.

The effects of different time patterns in presynaptic spike trains on the transmission of information across an inhibitory synapse is examined in the muscle receptor organs of the crayfish abdomen. With regular input, the system would be strongly affected by phaselocking (Perkel et al. 1964), and it is shown that a similar phenomenon would occur during closedloop inhibitory feedback. The conditions under which different degrees of phase-locking occur is studied in simple models of the system, and the model predictions is compared with experimental observations of pre- and postsynaptic spike trains. The results suggest that phaselocking is uncommon during the normal operation of these sense organs, due to the special design of its neuronal elements, which promote irregular time patterns of impulse firing in both receptors and inhibitory neurons.