Title Page 1 Title : Temporal dynamics of visual category representation in the macaque inferior temporal 2 cortex 3 Author names : Mohammad - Reza

17 Object categories are recognized at multiple levels of hierarchical abstractions. 18 Psychophysical studies have shown a more rapid perceptual access to the mid-level 19 category information (e.g. human faces) than the higher (superordinate; e.g. animal) or 20 the lower (subordinate; e.g. face identity) levels. Mid-level category members share many 21 features while few features are shared between members of different mid-level 22 categories. To better understand the neural basis of expedited access to mid-level 23 category information we examined neural responses of the inferior temporal (IT) cortex 24 of macaque monkeys viewing a large number of object images. We found an earlier 25 representation of mid-level categories in the IT population and single unit responses 26 compared to superordinate and subordinate level categories. The short latency 27 representation of mid-level category information shows that visual cortex first divides the 28 category shape space at its sharpest boundaries defined by high/low within/between 29 group similarity. This short latency mid-level category boundary map may be prerequisite 30 for representation of other categories at more global and finer scales. 31 32