Role of monkey superior colliculus in saccade averaging.
We have investigated the involvement of collicular movement cells in the monkey in the execution of averaging saccades, elicited by a visual double-step stimulus. We found that, qualitatively, most (12/14) movement cells were recruited during averaging saccades in roughly the same way as for comparable visually-elicited saccades to single targets (V-saccades). However, movement-cell responses during averaging saccades in trials where the target suddenly changed direction were often less intense than for a comparable V-saccade. In these cases, the averaging responses were observed to be also slower than V-saccades of the same amplitude. Firing rate and double-step saccade dynamics were found to be significantly correlated in 9/14 cells tested. Several hypotheses for the collicular role in the generation of averaging saccades are discussed.
van Opstal
A J
AJ
Department of Medical Physics and Biophysics, Nijmegen, The Netherlands.
van Gisbergen
J A
JA
D000200:Action Potentials; D000818:Animals; D005133:Eye Movements / Q000502:physiology*; D000882:Haplorhini / Q000502:physiology*; D008252:Macaca fascicularis; D008253:Macaca mulatta; D012438:Saccades / Q000502:physiology*; D013477:Superior Colliculi / Q000502:physiology*