INTACT PERCEPTUAL PRIMING IN A PATIENT WITH DAMAGE TO THE ANTERIOR INFERIOR TEMPORAL LOBES

We conducted three experiments to examine whether the anterior portion of the inferior temporal (IT) lobe is involved in the processing of v isual objects in humans. In monkeys, damage to this region results in severe deficits in perception and in memory for visual objects. Our st udy was designed to examine both these processes in a patient (DM) wit h bilateral damage to the anterior portion of the inferior temporal lo be. Neuropsychological examination revealed a significant semantic imp airment and a mild deficit in the discrimination of familiar objects f rom nonobjects. Despite these difficulties, the results of several stu dies indicated that DM was able to form and retain descriptions of the structure of objects. Specifically, DM showed normal perceptual primi ng for familiar and novel objects on implicit memory tests, even when the objects were transformed in size and left-right orientation. These results suggest that the anterior IT is not involved in (1) the stora ge of pre-existing structural descriptions of known objects, (2) the a bility to create new structural descriptions for novel objects, and (3 ) the ability to compute descriptions that are invariant with respect to changes in size and reflection. Instead, the anterior IT appears to provide the interface between structural descriptions of objects and their meanings.