You do not currently have permission to view the full text for this document. Please sign in to an account with an active subscription or contact support.
Cortical Microstimulation Influences Perceptual Judgments of Motion Direction. C. D. Salzman; K. H. Britten; W. T. Newsome. Nature. 346, 1990. Pp. 174-177.
To understand the basis of this feature-selective response, numerous electrophysiological studies have investigated the stimulus selectivity of single neurons and neuron groups in different cortical areas. Many neurons in the primary visual cortex are optimally responsive to simple stimuli such as light bars with a particular orientation, while single neurons in area V4 (color) respond maximally to stimuli of specific wavelength. Single neurons in the middle temporal area (MT, V5) of the extrastriate cortex are selectively responsive to motion in a preferred direction, and conversely are nonresponsive to motion in the opposite direction. As is the case for other sensory areas, neurons in V5 are arranged in columns such that there exists a series of cell columns selectively responsive to each motion direction for each region of the visual field.
Newsome and colleagues have begun to explore the relationship between neuronal activity and perception. The first of these papers correlates single cell responses to moving stimuli with the perceptual judgment of alert behaving monkeys. Macaque monkeys were trained to search for coherent movement of a subset of dots within a visual display of dots moving in random directions, and to "report" the