Visual area V4 is one of the visual areas in the extrastriate visual cortex. Anatomically it may be referred to as the prelunate gyrus.
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Subdivisions of V4

It comprises at least four regions (left and right V4d, left and right V4v)
Some groups report that it contains rostral and caudal subdivisions as well.

Connections

V4 is the third cortical area in the ventral stream, -Receives strong feedforward input from V2 and sending strong connections to the PIT.
-Receives direct inputs from V1, especially for central space.
-Additional weaker connections to V5 and dorsal prelunate gyrus (DP).

Functions

V4 is the first area in the ventral stream to show strong attentional modulation.
Most studies indicate that selective attention can change firing rates in V4 by about 20%.

Like V1, V4 is tuned for orientation, spatial frequency, and color.
Unlike V1, V4 is tuned for object features of intermediate complexity, like simple geometric shapes.
Visual area V4 is not tuned for complex objects such as faces, as areas in the inferior temporal gyrus are.

Recent work has shown that V4 exhibits long-term plasticity, encodes stimulus salience, is gated by signals coming from the frontal eye fields and shows changes in the spatial profile of its receptive fields with attention.