title: Combination of neuronal signals representing object-centered location and saccade direction in macaque supplementary eye field.
abstract: Neurons in the macaque supplementary eye field (SEF) fire at different rates in conjunction with planning saccades in different directions. They also exhibit object-centered spatial selectivity, firing at different rates when the target of the saccade is at the left or right end of a horizontal bar. To compare the rate of incidence of the two kinds of signal, and to determine how they combine, we recorded from SEF neurons while monkeys performed a task in which the target (a dot or the left or right end of a horizontal bar) could appear in any visual field quadrant. During the period when the target was visible on the screen and the monkey was preparing to make a saccade, many neurons exhibited selectivity for saccade direction, firing at a rate determined by the direction of the impending saccade irrespective of whether the target was a dot or the end of a bar. On bar trials, many of the same neurons exhibited object-centered selectivity, firing more strongly when the target was at the preferred end of the bar regardless of saccade direction. The rate of incidence of object-centered selectivity (33%) was lower overall than that of saccade-direction selectivity (56%). Signals related to saccade direction and the object-centered location of the target tended to combine additively. The results suggest that the SEF is at a transitional stage between representing the object-centered command and specifying the parameters of the saccade.
authors.affiliation: Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA 15213-2683, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Moorman
authors.forename: Carl R
authors.initials: CR
authors.lastname: Olson
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D003213:Conditioning, Psychological / Q000502:physiology; D003463:Cues; D005123:Eye; D007839:Functional Laterality; D008253:Macaca mulatta; D008297:Male; D009474:Neurons / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012044:Regression Analysis; D012438:Saccades / Q000502:physiology*; D014793:Visual Cortex / Q000166:cytology*; D014794:Visual Fields / Q000502:physiology*