1. Get this article [1]Chelazzi L, Miller EK, Duncan J, Desimone R. A neural basis for visual search in inferior temporal cortex. Nature 1993; 363: 345-347. We will read this in about 2 weeks

2. The Role of “Extrastriate” Areas V4 and V5 are doubly-dissociated in lesion literature:

3. The Role of “Extrastriate” Areas V4 and V5 are doubly-dissociated in lesion literature: –achromatopsia (color blindness): there are many forms of color blindness cortical achromatopsia arises from lesions in the area of V4 Depth and texture discrimination remain intact Typically contralateral to lesion singly dissociable from motion perception deficit - patients with V4 lesions have other visual problems, but motion perception is substantially spared

4. The Role of “Extrastriate” Areas V4 lesions also lead to deficits in perceiving complex forms and illusory contours But not brightness, orientation or motion

5. The Role of “Extrastriate” Areas V4 and V5 are doubly-dissociated in lesion literature: –akinetopsia (motion blindness): bilateral lesions to area V5 (extremely rare) severe impairment in judging direction and velocity of motion - especially with fast-moving stimuli visual world appeared to progress in still frames similar effects occur when M-cell layers in LGN are lesioned in monkeys

6. The Role of “Extrastriate” Areas Motion deficits also can be triggered using TMS Timing of stimulation matters! What does this suggest about the flow of information in the visual pathway?

7. Any Questions?