Fig. 4.

Input to modulatory and sensory neurons during the C15-induced CMP in isolated cerebral ganglia. A, Modulatory neuron C4 received large EPSPs that drove it above threshold during the CMP, whereas its neighbor C5received much smaller EPSPs that were one-for-one with those inC4 (see record to the right, showing input at an expanded time-base). These EPSPs had little effect on the firing rate of C5. B, The sensory mechanoafferentC2 received fast IPSPs during the CMP. The MCC, which has both central and peripheral modulatory roles, was slowly depolarized. There were also a few faster potentials in theMCC associated with the peak of some of the cyclical depolarizations, which were not one-for-one with the PSPs in other neurons (see record to the right). Arrowsindicate points on the slow record from which the faster time-base records to the right were taken.