EFFECTOR SPECIFIC AND NON - SPECIFIC ACTIVITY IN FRONTAL EYE FIELDS

B.M.Lawrence; L.H.Snyder^*

Effector Specific and Non-Specific Activity in Frontal Eye Fields Bonnie M. Lawrence and Lawrence H. Snyder Washington University School of Medicine Recent investigations of frontal eye fields (FEF) have primarily focused on the responses of neurons during the planning and execution of eye movements. We compared the responses of neurons during the planning and execution of eye versus arm movements to determine the extent to which such responses are effector specific. To accomplish this, an effector cue was presented, signaling either an eye or an arm movement trial. Following a delay period, a spatial target was presented, signaling both the goal and the initiation of the movement. Sixty-eight cells were recorded from two rhesus monkeys. During the delay period, when only the effector was known, the responses of all types of FEF neurons were effector specific, with 1.55 greater population-averaged activity on eye compared to arm movement trials. When both effector and goal were known, immediately prior to movement execution, motor cells were somewhat motor specific (1.44 greater population activity on eye compared to arm trials). Both visual and visuomotor cells were effector non-specific, despite being effector specific during the planning phase. That visual cells demonstrate effector specific responses is inconsistent with previous notions of visual cells as a generic salience map, and is evidence instead for a specific relationship with eye movements That visual cells lose effector specificity at the time of motor execution may suggest that, on arm movement trials, a plan for an eye movement is formed but cancelled at a later stage.
Supported by: NIH, EJLB & McDonnell Foundations

Citation: B.M.Lawrence, L.H.Snyder. EFFECTOR SPECIFIC AND NON - SPECIFIC ACTIVITY IN FRONTAL EYE FIELDS Program No. 622.8. 2002 Abstract Viewer/Itinerary Planner. Washington, DC: Society for Neuroscience, 2002. CD-ROM.