GATING OF NEURONAL RESPONSES IN MACAQUE PRIMARY VISUAL-CORTEX BY AN ATTENTIONAL SPOTLIGHT

NEURONAL responses were recorded from the striate cortex of monkeys tr ained to perform visual discrimination at locations in the visual fiel d to which their attention was drawn. A subset of neurons showed vigor ous responses to visual stimuli for trials in which the monkey was dir ecting its attention to the respective receptive field location. In tr ials where attention is directed elsewhere, responses to the same stim uli were significantly reduced. In some cells the early response compo nent was not modulated by attention, but later components were affecte d by the locus of attention. The results suggest the operation of a fe edback in the paradigm that spotlights a topographically restricted ar ea of V1 for further processing at higher levels. (C) 1998 Rapid Scien ce Ltd.