Beyond the core face-processing network: intracerebral stimulation of a face-selective area in the right anterior fusiform gyrus elicits transient prosopagnosia

Abstract

According to neuropsychological evidence, a distributed network of face-selective regions of the ventral visual pathway supports face recognition. However, fMRI studies have generally confined to the posterior face-selective areas, i.e., the occipital face area (OFA) and the fusiform face area (FFA). There is recent evidence that intracranial electrical stimulation of the OFA and FFA elicits face recognition impairments. Here we were able to test for face recognition in a patient implanted with depth electrodes in the anterior temporal cortex. Electrically stimulating the right anterior fusiform gyrus, in a region located anteriorly to the FFA, induced a transient inability to recognize familiar faces (see Figure 1 in additional information; movies available). This region was shown face-selective as revealed by intracerebral face-selective event-related potentials and gamma band activity recorded at these critical electrodes. However, no fMRI face-selective responses were found in this region due to severe BOLD signal drop-out caused by the ear canal artifacts (see Figure 2 in additional information). These results point to a causal role in face recognition of the right anterior fusiform gyrus and more generally of face-selective areas located beyond the "core" face processing network in the anterior ventral temporal cortex. It also illustrates the diagnostic value of intracerebral recordings and stimulation in understanding the neural basis of face recognition and visual recognition in general. Meeting abstract presented at VSS 2016