Visual categorization and the inferior temporal cortex.

We investigated the effects of categorization on the representation of stimulus features in combined psychophysical-electrophysiological experiments. We used parameterized line drawings of faces and fish as stimuli, and we varied the relevance of the different features for the categorization task. The psychophysical and electrophysiological data support an exemplar-based framework for visual object recognition. We recorded from visual neurons in the anterior inferior temporal (IT) cortex of macaque monkeys, while they were performing a categorization task. The visual neurons did not respond selectively to one stimulus set, or to one category. The majority of the anterior IT feature selective neurons were tuned for features that were diagnostic for the categorization task. We argue that this fine-tuning of the neurons reflects the perceptual sensitization to the diagnostic features.