The Effect of Attention on the Responses of Individual Visual Neurons

Abstract

Performance on sensory tasks depends not only on the quality of the sensory signals that are available, but also on the aspects of the sensory signals that the subject attends to. Recordings from individual neurons in trained, behaving monkeys have shown that attention to particular visual stimuli alters the way that those stimuli are represented in cerebral cortex. The primary effect of attention appears to be a gain change, which increases the responses of neurons that represent attended stimuli while decreasing the responses of other neurons. This gain change affects responses to all stimuli proportionately, without affecting the selectivity of neurons or the stimulus that they prefer. This effect alone can explain much of the improvement in behavioral performance that is conferred by attention.