Figure 11.

Flexion reflex-selective motoneuron. A, Reconstruction of this motoneuron, showing its soma and dendrites (blue), along with its axon (red); inset, ChAT immunoreactivity (green) associated with soma and dendrites (red). B, C, Intracellular recording from this motoneuron during caudal scratching (B) and swimming (C). Blue bar indicates the period of swim-evoking stimulation. D, Intracellular recording from this motoneuron during flexion reflex; boxed region expanded in E. F, Spike-triggered average (from 195 intracellular motoneuron spikes) of the HF nerve activity along with the intracellular spike. MN, Motoneuron; IT-KE and FT-KE, knee-extensor nerves.