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Competing Interests: The author declares no conflict of interest.

Recognizing the identity of a face is computationally challenging, because it requires distinguishing between similar images depicting different people, while recognizing even very different images depicting a same person. Previous human fMRI studies investigated representations of face identity in the presence of changes in viewpoint and in expression. Despite the importance of holistic processing for face recognition, an investigation of representations of face identity across different face parts is missing. To fill this gap, we investigated representations of face identity and their invariance across different face halves. Information about face identity with invariance across changes in the face half was individuated in the right anterior temporal lobe, indicating this region as the most plausible candidate brain area for the representation of face identity. In a complementary analysis, information distinguishing between different face halves was found to decline along the posterior to anterior axis in the ventral stream., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Neuropsychological evidence has highlighted the role of the anterior temporal lobes in the processing of conceptual knowledge. That putative role is only beginning to be investigated with fMRI as methodological advances are able to compensate for well-known susceptibility artifacts that affect the quality of the BOLD signal. In this article, we described differential BOLD activation for pictures of animals and manipulable objects in the anterior temporal lobes, consistent with previous neuropsychological findings. Furthermore, we found that the pattern of BOLD signal in the anterior temporal lobes is qualitatively different from that in the fusiform gyri. The latter regions are activated to different extents but always above baseline by images of the preferred and of the nonpreferred categories, whereas the anterior temporal lobes tend to be activated by images of the preferred category and deactivated (BOLD below baseline) by images of the nonpreferred category. In our experimental design, we also manipulated the decision that participants made over stimuli from the different semantic categories. We found that in the right temporal pole, the BOLD signal shows some evidence of being modulated by the task that participants were asked to perform, whereas BOLD activity in more posterior regions (e.g., the fusiform gyri) is not modulated by the task. These results reconcile the fMRI literature with the neuropsychological findings of deficits for animals after damage to the right temporal pole and suggest that anterior and posterior regions within the temporal lobes involved in object processing perform qualitatively different computations.

When we perform a cognitive task, multiple brain regions are engaged. Understanding how these regions interact is a fundamental step to uncover the neural bases of behavior. Most research on the interactions between brain regions has focused on the univariate responses in the regions. However, fine grained patterns of response encode important information, as shown by multivariate pattern analysis. In the present article, we introduce and apply multivariate pattern dependence (MVPD): a technique to study the statistical dependence between brain regions in humans in terms of the multivariate relations between their patterns of responses. MVPD characterizes the responses in each brain region as trajectories in region-specific multidimensional spaces, and models the multivariate relationship between these trajectories. We applied MVPD to the posterior superior temporal sulcus (pSTS) and to the fusiform face area (FFA), using a searchlight approach to reveal interactions between these seed regions and the rest of the brain. Across two different experiments, MVPD identified significant statistical dependence not detected by standard functional connectivity. Additionally, MVPD outperformed univariate connectivity in its ability to explain independent variance in the responses of individual voxels. In the end, MVPD uncovered different connectivity profiles associated with different representational subspaces of FFA: the first principal component of FFA shows differential connectivity with occipital and parietal regions implicated in the processing of low-level properties of faces, while the second and third components show differential connectivity with anterior temporal regions implicated in the processing of invariant representations of face identity. [ABSTRACT FROM AUTHOR]

Every day we encounter dozens of people, and in order to interact with them appropriately we need to recognize their identity. The face is a crucial source of information to recognize a person's identity. However, recognizing the identity of a face is challenging because it requires distinguishing between very similar images (e.g., the front views of two different faces) while categorizing very different images (e.g., a front view and a profile) as the same person. Neuroimaging has the whole-brain coverage needed to investigate where representations of face identity are encoded, but it is limited in terms of spatial and temporal resolution. In this article, we review recent neuroimaging research that attempted to investigate the representation of face identity, the challenges it faces, and the proposed solutions, to conclude that given the current state of the evidence the right anterior temporal lobe is the most promising candidate region for the representation of face identity. [ABSTRACT FROM AUTHOR]