Neurophysiology of the motoneurons of the external oculomotor nucleus in the waking cat

Abstract

The spontaneous and visually induced activity of abducens motoneurons has been recorded in the alert cat.Motoneurons were identified by their antidromic activation from the ipsilateral abducens nerve.All identified motoneurons appeared related to both the position and velocity of the eye in the horizontal plane, although distributed in a wide range.Neural time constants were also measured, showing a mean value similar to that of the mechanical time constant of the oculomotor plant.According to present results, abducens motoneurons of cats and monkeys are very similar, notwithstanding some differences in their activities during saccadic movements.