Walsh & Hoyt: Cortical Areas V3 and V3A

The most detailed information regarding the organization of the visual cortices comes from monkeys, and this body of information provides moderate detail on only three areas: V1, V2, and MT. The current frontier of study is of area V3, for which there are good anatomic data of its interconnections but only recently a compelling picture of its retinotopy. Area V3d (i.e., dorsal) has more connections with V1 than any other area, although these are less numerous than the connections between areas V1 and V2. Area V3, which is relatively small (i.e., roughly half the width of V2) is located adjacent to the boundary between areas 18 and 19 of Brodmann (area V3 is not synonymous with area 19 of Brodmann, which occupies a large area laterally where it surrounds area V2).