Fig. 37. Motoneuron activity underlying a saccade. Twenty degrees saccadic eye movement ending in primary position (top trace) is shown along with motoneuron firing rate in the agonist (middle trace) and antagonist (lower trace) muscles. At least seven phases of neural activity can be distinguished. Phases 3 to 7 taken together constitute the pulse-slide-step saccadic input. The traces have been shifted to align saccade onset with onset of neural modulation. Note that transient phases 5 and 6 occur after the eye has come to rest. |