Downimg matlab5/23/2023 ![]() ![]() 2000) proposes (in part) a hierarchical scheme in which the OFA analyzes individual facial features, superior temporal sulcus analyzes facial expressions and lip movements, and the FFA analyzes the invariant, identity-related aspects of the face (but for challenges to this scheme see Calder and Young 2005 Schlitz and Rossion 2006). 2005).Īn influential model of face processing ( Haxby et al. 1997), which is found on the lateral fusiform gyrus, where it closely overlaps the FBA ( Peelen and Downing 2005b Peelen et al. 2003), which is found on the ventral surface of the occipital lobe, and the fusiform face area (FFA Kanwisher et al. 1): the occipital face area (OFA Kanwisher et al. In humans, two ventral occipitotemporal areas respond selectively to faces, relative to scenes and nonface objects (see Fig. In the macaque, fMRI studies have identified adjacent or overlapping face- and body-selective regions of superior temporal sulcus ( Pinsk et al. The functional neuroanatomy of face and body processing are also similar in some ways. Finally, inversion of both faces and bodies interferes with their identification, relative to other object kinds ( Reed et al. Second, both stimuli are biologically relevant and carry important information about conspecifics, such as their gender, actions, and intentions. ![]() Most obviously, bodies and faces are nearly always perceived together in space and time-seeing a body without the face or vice versa is rare. There are several reasons to think the cortical systems that analyze bodies and faces might be similar. EBA, extrastriate body area OFA, occipital face area FFA, fusiform face area FBA, fusiform body area.Ī possible basis for understanding the relative functional contributions of the EBA and FBA to body perception comes from our understanding of face processing. tools, each at a threshold of P < 0.0001. Regions were defined by bodies or faces vs. Regions of interest are identified for illustrative purposes. 1.Rendering of the cortical surface of one individual's right hemisphere. Although these two areas are thought to contribute to the perception of bodies and/or body parts, to date there is no evidence on whether and how they might be functionally distinguished.įIG. The EBA is found at the posterior end of the inferior temporal sulcus and the FBA is found in the lateral posterior fusiform gyrus (see Fig. 2001, 2006a, b, 2007 Peelen and Downing 2005c) and FBA ( Peelen and Downing 2005b Peelen et al. These regions have been designated the extrastriate and fusiform body areas: EBA ( Downing et al. Functional magnetic resonance imaging (fMRI) studies have previously identified two regions of extrastriate visual cortex that are highly sensitive to visual depictions of the human body, relative to nonbody control objects. Accurate perception of the human body and its individual parts can be seen as a necessary component of this broader task. The ability to identify and interpret the actions and intentions of other people is a crucial human social skill. Specifically, we hypothesize that the EBA analyzes bodies at the level of parts (as has been proposed for faces in the OFA), whereas FBA (by analogy to FFA) may have a role in processing the configuration of body parts into wholes. We propose an interpretation of these results by analogy to nearby face-selective regions occipital face area (OFA) and fusiform face area (FFA). In a third experiment we demonstrate that the response pattern seen in EBA does not extend to adjacent motion-selective human midtemporal area. In contrast, the FBA shows a steplike function, with no significant selectivity for individual fingers or hands. We found a gradual increase in the selectivity of the EBA as a function of the amount of body shown. A second experiment determined the selectivity of these regions for body and body part stimuli relative to closely matched control images. ![]() Specifically we measured in these two areas the magnitude of fMRI response as a function of the amount of the human figure that is visible in the image, in the range from a single finger to the entire body. This study examined the contributions of two previously identified brain regions-the extrastriate and fusiform body areas (EBA and FBA)-to the visual representation of the human form.
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