Activity of neurons in the deep layers of the cat superior colliculus correlated with slow eye movements.

In the encéphale isolé cats in state of drowsiness and sleep and in darkness, the spike activity of a population of neurons in the superior collicules is modulated in relation to the slow movement of the eyes. These neurons are all located in the deep layers of the colliculus and belong to a larger population which had been previously to discharge in correspondence with saccadic movements. The correlation between neuronal activity and slow movements is not present continuously and may be obscured by a number of factors. Also when the correlation is present there is always some degree of independence between strength and time course of the discharge on one side, and extent and time course of movement on the other.