Abstract
Previous fMRI studies showed several face-selective areas in human visual cortex, including the Fusiform Face Area (FFA). Following results in macaques, recent fMRI studies also demonstrated face-selective regions in the human anterior temporal lobe (ATFP), which may be involved in higher-level functions such as face recognition. To clarify the contribution of category-selective regions within anterior temporal lobe during recognition, we measured fMRI activity during a 1-back recognition task (n = 14), based on computer-generated faces and houses relative to a 1-back dot-location task, using identical stimuli. As controls, we tested the effects of : 1) face and house rotation in depth and 2) face contrast reversal; both factors are known to affect recognition. The level of task difficulty was controlled by independently manipulating the contrast of the faces, houses and dots. The facial recognition task produced higher activity confined to FFA and ATFP, relative to the 1-back dot-location task. Consistent with our hypothesis, fMRI activity in ATFP was more related to recognition compared to FFA: 1) Over all facial recognition conditions, subjects' response accuracy was significantly correlated with BOLD amplitude in ATFP, but not in FFA; 2) Compared to house recognition, higher response modulations were found during face recognition in ATFP, but not in FFA. Otherwise-equivalent house recognition task produced a quite different pattern of activity. House recognition strongly increased activity in previously undescribed patches within the anterior temporal lobe, plus expected increases in known ‘place-selective’ areas such as the Parahippocampal Place Area (PPA), Transverse Occipital Sulcus (TOS) and Retro-Splenial Cortex (RSC). These results show that face recognition activates higher-order regions within anterior temporal lobe, relatively more than previously described face-processing areas located more posteriorly in the brain. Analogously, house recognition produced activity that extended into anterior temporal lobe – but those house-recognition patches were distinct from the patches activated by face recognition.