Abstract
Primates have specialized domains in inferior temporal (IT) cortex that are responsive to particular object categories. Recent fMRI studies have shown that retinotopic maps cover much of category-selective IT cortex in humans and monkeys. So far, retinotopy in monkey IT cortex has been reported within and around the lower bank of the STS (Kolster et al. 2014; Janssens et al. 2014). In the present study, we confirm this previously reported retinotopy and extend these prior findings by examining retinotopy in the ventral-most regions of IT - occipital temporal sulcus (OTS). We identified two retinotopic areas, referred to as OTS1 and OTS2, which have not been described previously in the macaque. These new regions are located ventral to retinotopic areas V4A and PIT. Both regions contain contralateral representations of the periphery with little coverage of central visual space. OTS1/2 show selectivity for scenes compared to objects, faces, and bodies. Our results resolve the relationship between scene-selective areas in humans (Aguirre et al. 1996, Epstein and Kanwisher 1998) and primates (Nasr et al. 2011; Kornblith et al. 2013). OTS1/2 overlap with the functionally defined place area, LPP. Further, the visual field organization of OTS1/2 corresponds well with the organization of scene-selective retinotopic areas PHC1/2 in humans (Arcaro et al. 2009). Our data provide new evidence that monkey LPP is the homologue to human area PPA. Our results illustrate parallels in the retinotopic organization between primate species. First, the broad eccentricity bias across human ventral temporal cortex (Hasson et al. 2002) is clearly present in macaque IT cortex. Second, we find that the extent of retinotopy in macaque IT cortex roughly matches that in humans. Recent results from our lab suggest that this retinotopic organization is present at birth and is likely fundamental in guiding experience-dependent development of IT.
Meeting abstract presented at VSS 2017