Fig. 12. Double recordings from a swim motor neuron in the inner nerve ring (top traces of each pair) and a circular muscle cell approximately 0.5 mm from the neuron recording site (bottom traces). In A, a spontaneous radial response occurred between the first and second swim. Note the inhibition of neuronal action potential burst and the smaller muscle event with a slow rise time. In the third swim, the preparation had partially recovered from the inhibition, and it was fully recovered by the fourth swim. (B) Another radial response from the same preparation produced total inhibition of the neuronal burst in the second swim (which occurs after a long delay), a single neuronal spike in the third swim, and full recovery on the fourth. Note the changes in the muscle action potentials during the inhibition.