Selectivity for the configural cues that identify the gender, ethnicity, and identity of faces in human cortex

Abstract

We used psychophysical and functional MRI (fMRI) adaptation to examine how and where the visual configural cues underlying identification of facial ethnicity, gender, and identity are processed. We found that the cortical regions showing selectivity to these cues are distributed widely across the inferior occipital cortex, fusiform areas, and the cingulate gyrus. These regions were not colocalized with areas activated by traditional face area localizer scans. Traditional face area localizer scans isolate regions defined by stronger fMRI responses to a random series of face images than to a series of non-face images. Because these scans present a random assortment of face images, they presumably produce the strongest responses within regions containing neurons that are face-sensitive but not highly tuned for face type. These areas might be expected to show only weak selective adaptation effects. In contrast, the largest responses to our selective adaptation paradigm would be expected within areas containing more selectively tuned neurons that might be expected to show only a sparse collective response to a series of random faces. Many aspects of face processing (e.g., prosopagnosia, recognition, and configural vs. featural processing) are likely to rely heavily on regions containing high proportions of neurons that show selective tuning for faces.

Neural correlates of after-effects caused by adaptation to multiple face displays

“…These results are supported by the findings of Afraz and Cavanagh (2008), who found that presenting two faces along the anti-face axis reduced the identity specific FAE equally in the visual field. This property of statistical face adaptation may be a useful tool in the future to study further the independence of various facial properties, such as contingent after-effects (Fox and Barton 2007;Jaquet et al 2007;Jaquet and Rhodes 2008;Jeffery et al 2007;Little et al 2008;Ng et al 2006;Rhodes et al 2004;Sohn and Seiffert 2006;Watson and Clifford 2006;Yamashita et al 2005).…”

Neural correlates of own- and other-race face perception: Spatial and temporal response differences

“…At a more general level of analysis, Ng et al (2006) examined the neural codes underlying the facial category representations of ethnicity and gender using an fMR-adaptation (fMR-A) method (e.g., GrillSpector et al, 1999), which they combined with a psychophysics-based face adaptation paradigm (e.g., Webster et al, 2004). FMR-A methods make use of the finding that neural responses tend to adapt with repeated presentations of the "same" stimulus (e.g., the fMR-A method, Grill-Spector et al, 1999;response suppression, Henson et al, 2000).…”

Position specificity of adaptation-related face aftereffects

“…The full positional invariance of this area for both contralateral and ipsilateral stimuli [50] suggests a high degree of spatial invariance. On the other hand, neuropsychological [80] and imaging [81,82] studies suggest that facial gender is processed in other cortical areas. Thus, it is possible that the two studies tapped into separate neural mechanisms of face perception, one responsible for recognition while the other responsible for gender decisions, and these two mechanisms have different retino/spatiotopic representations.…”