Face recognition is of central importance for primate social behavior. In both humans and macaques, the visual analysis of faces is supported by a set of specialized face areas. The precise organization of these areas and the correspondence between individual macaque and human face-selective areas are debated. Here, we examined the organization of face-selective regions across the temporal lobe in a large number of macaque and human subjects. Macaques showed 6 regions of face-selective cortex arranged in a stereotypical pattern along the temporal lobe. Human subjects showed, in addition to 3 reported face areas (the occipital, fusiform, and superior temporal sulcus face areas), a face-selective area located anterior to the fusiform face area, in the anterior collateral sulcus. These results suggest a closer anatomical correspondence between macaque and human face-processing systems than previously realized.face processing ͉ fMRI ͉ evolution ͉ form perception ͉ vision F or primates as social animals, faces are immensely important stimuli, carrying a wealth of social information. Given the paramount importance of face recognition for primates, the underlying neural mechanisms must have been subject to the highest selective pressure through the course of evolution (1, 2). As a consequence, a common primate face recognition system may exist, providing the basic scaffold around which speciesspecific specializations may have then evolved.In humans, extensive behavioral and neurological evidence suggests that specialized mechanisms exist for processing faces (3, 4). This notion is supported by functional imaging experiments showing several face-selective areas in the temporal lobe, including the fusiform face area (FFA), the occipital face area (OFA), and a face area in the superior temporal sulcus (STS-FA) (5). Furthermore, evidence has been put forward that these areas have different functional specializations, suggesting that the OFA is involved in processing face parts (6), the STS-FA in processing changeable aspects such as gaze direction (7), and the FFA in processing identity (8, 9). Thus, the human faceprocessing system seems to be organized around 3 specialized face areas (10).In macaque monkeys, the existence of face-selective cortical areas, so called ''face patches,'' was demonstrated by fMRI (11,12). Tsao et al. (11) reported 3 regions of face-selective cortex in inferotemporal (IT) cortex, organized along an anteriorposterior axis. This finding immediately raised the question of how macaque face patches relate to those of humans and, more generally, whether there is a common functional organization for face processing in primates. By computationally stretching the cortical surface of the macaque brain over the human cortical surface, the macaque middle face patch was found to lie quite close to the human FFA (11). The human FFA and macaque middle face patch were also the largest within each species.Although this spatial correspondence analysis is, of course, a far cry from demonstrating homology, it rais...

The brain processes objects through a series of regions along the ventral visual pathway, but the circuitry subserving the analysis of specific complex forms remains unknown. One complex form category, faces, selectively activates six patches of cortex in the macaque ventral pathway. To identify the connectivity of these face patches, we used electrical microstimulation combined with simultaneous functional magnetic resonance imaging. Stimulation of each of four targeted face patches produced strong activation, specifically within a subset of the other face patches. Stimulation outside the face patches produced an activation pattern that spared the face patches. These results suggest that the face patches form a strongly and specifically interconnected hierarchical network.

Imaging studies are consistent with the existence of brain regions specialized for color, but electrophysiological studies have produced conflicting results. Here we address the neural basis for color, using targeted single-unit recording in alert macaque monkeys, guided by functional magnetic resonance imaging (fMRI) of the same subjects. Distributed within posterior inferior temporal cortex, a large region encompassing V4, PITd, and posterior TEO that some have proposed functions as a single visual complex, we found color-biased fMRI hotspots that we call "globs," each several millimeters wide. Almost all cells located in globs showed strong luminance-invariant color tuning and some shape selectivity. Cells in different globs represented distinct visual field locations, consistent with the coarse retinotopy of this brain region. Cells in "interglob" regions were not color tuned, but were more strongly shape selective. Neither population was direction selective. These results suggest that color perception is mediated by specialized neurons that are clustered within the extrastriate brain.

In primates, specialized occipital-temporal face areas support the visual analysis of faces, but it is unclear whether similarly specialized areas exist in the frontal lobe. Using functional magnetic resonance imaging in alert macaques, we identified three discrete regions of highly face-selective cortex in ventral prefrontal cortex, one of which was strongly lateralized to the right hemisphere. These prefrontal face patches may constitute dedicated modules for retrieving and responding to facial information.

Increasing stroke severity was associated with progressive loss of overall autonomic modulation, decline in parasympathetic tone, and baroreflex sensitivity, as well as progressive shift toward sympathetic dominance. All autonomic changes put patients with more severe stroke at increasing risk of cardiovascular complications and poor outcome. NIHSS scores are suited to predict risk of autonomic dysregulation and can be used as premonitory signs of autonomic failure.