Visual Responses to Targets and Distracters by Inferior Temporal Neurons After Lesions of Extrastriate Areas V4 and TEO

While lesions of visual areas V4 and TEO only modestly affect discrimination of isolated objects, they significantly impair the ability to selectively attend to an object surrounded by distracters. To test whether such deficits result from a loss of inputs to higher order areas, we recorded from area TE neurons after removing portions of V4 and TEO in a monkey. Responses to isolated targets in a lesion-affected visual quadrant were substantially preserved, indicating that TE still receives information even after removing a major source of input. Distracters increased or decreased the response to targets more in the lesion-affected than in the normal quadrant, supporting the idea that V4 and/or TEO are sites where top-down attentional inputs filter out distracting stimuli.