The occipital face area is causally involved in the formation of identity-specific face representations

Brain Struct Funct. 2017 Dec;222(9):4271-4282. doi: 10.1007/s00429-017-1467-2. Epub 2017 Jul 11.

Abstract

Transcranial magnetic stimulation (TMS) and neuroimaging studies suggest a role of the right occipital face area (rOFA) in early facial feature processing. However, the degree to which rOFA is necessary for the encoding of facial identity has been less clear. Here we used a state-dependent TMS paradigm, where stimulation preferentially facilitates attributes encoded by less active neural populations, to investigate the role of the rOFA in face perception and specifically in image-independent identity processing. Participants performed a familiarity decision task for famous and unknown target faces, preceded by brief (200 ms) or longer (3500 ms) exposures to primes which were either an image of a different identity (DiffID), another image of the same identity (SameID), the same image (SameIMG), or a Fourier-randomized noise pattern (NOISE) while either the rOFA or the vertex as control was stimulated by single-pulse TMS. Strikingly, TMS to the rOFA eliminated the advantage of SameID over DiffID condition, thereby disrupting identity-specific priming, while leaving image-specific priming (better performance for SameIMG vs. SameID) unaffected. Our results suggest that the role of rOFA is not limited to low-level feature processing, and emphasize its role in image-independent facial identity processing and the formation of identity-specific memory traces.

Keywords: Face perception; Identity; Occipital face area; Priming; Transcranial magnetic stimulation.

MeSH terms

  • Adult
  • Analysis of Variance
  • Brain Mapping*
  • Decision Making
  • Face*
  • Female
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Male
  • Occipital Lobe / diagnostic imaging
  • Occipital Lobe / physiology*
  • Pattern Recognition, Visual / physiology*
  • Photic Stimulation
  • Reaction Time / physiology
  • Transcranial Magnetic Stimulation
  • Young Adult