Differential responses for faces and objects in auditory cortex and superior temporal sulcus

Behavioral and neural evidence suggests that faces are represented as a distinct class from other objects. Face-selective single unit reponses are most commonly found in unimodal visual areas such as the lower bank of superior temporal sulcus and the contiguous inferotemporal region. We investigated 1) the degree to which such face/object classifications occur beyond unimodal visual areas and 2) whether Greebles, an artificial set of homogeneous stimuli, elicit responses from sites that are also face-responsive. Simultaneous electrode recordings were collected from auditory cortex and the upper bank of the superior temporal sulcus (uSTS). The monkey passively viewed three classes of static images: monkey faces, various clip-art objects, and Greebles. The local field potential (LFP) response to faces was characterized by a peak negativity around 100ms after stimulus onset in both auditory cortex and uSTS. Both regions responded to objects and Greebles; however, their LFPs typically had a longer latency to peak, and a different response profile when compared with the face response. The relationship between the LFP response and spiking activity will also be described