The N170 waveform is larger over posterior temporal cortex when healthy subjects view faces than when they view other objects. Source analyses have produced mixed results regarding whether this effect originates in the fusiform face area (FFA), lateral occipital cortex, or superior temporal sulcus (STS), components of the core face network. In a complementary approach, we assessed the face-selectivity of the right N170 in five patients with acquired prosopagnosia, who also underwent structural and functional magnetic resonance imaging. We used a non-parametric bootstrap procedure to perform single-subject analyses, which reliably confirmed N170 face-selectivity in each of 10 control subjects. Anterior temporal lesions that spared the core face network did not affect the face-selectivity of the N170. A face-selective N170 was also present in another subject who had lost only the right FFA. However, face-selectivity was absent in two patients with lesions that eliminated the occipital face area (OFA) and FFA, sparing only the STS. Thus while the right FFA is not necessary for the face-selectivity of the N170, neither is the STS sufficient. We conclude that the face-selective N170 in prosopagnosia requires residual function of at least two components of the core face-processing network.
|Original language||English (US)|
|Number of pages||11|
|State||Published - Jul 2011|
Bibliographical noteFunding Information:
This work was presented at the annual meeting of the Vision Sciences Society in Naples, May 2010. It was supported by CIHR grants MOP-77615 and MOP-102567 . K.A.D. was supported by a grant from the Michael Smith Foundation for Health Research (MSFHR) and the Natural Sciences and Engineering Research Council (NSERC) of Canada. B.C.D. was supported by a grant from BBSRC ( BB/F022875/1 ). C.J.F. was supported by a Canadian Institutes of Health Research Canada Graduate Scholarship Doctoral Research Award and a MSFHR Senior Graduate Studentship. G.I. was supported by MSFHR and the Alzheimer Society of Canada (ASC). T.C.H. was supported by NSERC and the Michael Smith Foundation for Health Research. J.J.S.B. was supported by a Canada Research Chair and a Senior Scholarship from the Michael Smith Foundation for Health Research.
- Acquired prosopagnosia
- Event related potentials
- Face perception