Prosegmental motor neurons
Prosegmental motor neuron activity causes movement in the anterior segment of the animal (Fig. 1).
Anatomy and Location
Prosegmental motor neurons typically have small (40-80um) and non-distinctive soma. Most soma of prosegmental motor neurons were located in sector II, with a few also found in Sector Ia. The soma were primarily clustered around the pedal connective innervating each sector (Fig. 2).
Motor effects and electrophysiology
Prosegmental motor neurons can be further divided in to three subclasses based on their motor effects. 1. Dorsoventral (transverse) contractors causing lateral tegument constriction transversely. 2. Longitudinal contractors causing lateral tegument constriction longitudinally. 3. Longitudinal contractors causing anterior dorsal neck contraction.