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Location, Location, Location: Alterations in the Functional Topography of Face- but not Object- or Place-Related Cortex in Adolescents with Autism.

Scherf KS, Luna B, Minshew N, Behrmann M - Front Hum Neurosci (2010)

Bottom Line: With these data, we mapped the functional topography of category-selective activation for faces bilaterally in the fusiform gyrus, occipital face area, and posterior superior temporal sulcus.Additionally, we mapped category-selective activation for objects in the lateral occipital area and for places in the parahippocampal place area in the two groups.Our findings do not indicate a generalized disruption in the development of the entire ventral visual pathway in autism.

View Article: PubMed Central - PubMed

Affiliation: Cognitive Neuroscience Laboratory, Department of Psychology, Center for the Neural Basis of Cognition, Carnegie Mellon University Pittsburgh, PA, USA.

ABSTRACT
In autism, impairments in face processing are a relatively recent discovery, but have quickly become a widely accepted aspect of the behavioral profile. Only a handful of studies have investigated potential atypicalities in autism in the development of the neural substrates mediating face processing. High-functioning individuals with autism (HFA) and matched typically developing (TD) controls watched dynamic movie vignettes of faces, common objects, buildings, and scenes of navigation while undergoing an fMRI scan. With these data, we mapped the functional topography of category-selective activation for faces bilaterally in the fusiform gyrus, occipital face area, and posterior superior temporal sulcus. Additionally, we mapped category-selective activation for objects in the lateral occipital area and for places in the parahippocampal place area in the two groups. Our findings do not indicate a generalized disruption in the development of the entire ventral visual pathway in autism. Instead, our results suggest that the functional topography of face-related cortex is selectively disrupted in autism and that this alteration is present in early adolescence. Furthermore, for those HFA adolescents who do exhibit face-selective activation, this activation tends to be located in traditionally object-related regions, which supports the hypothesis that perceptual processing of faces in autism may be more akin to the perceptual processing of common objects in TD individuals.

No MeSH data available.


Related in: MedlinePlus

Individual subject variability in location, size, and magnitude of face-selective activation in the fusiform gyrus (A–D) and OFA (E–H). The individually defined face contrast map for each participant in each group, represented in a unique color, was thresholded using the FDR procedure (q < 0.10) and overlaid onto a single inflated brain. The respective group-defined ROIs are illustrated in white. (A) Ninety percent of the TD individuals exhibited face-selective activation in the right fusiform gyrus, with 60% in the TD group-defined right FFA ROI. (B) In contrast, 70% of the HFA exhibited face-selective activation in the right fusiform gyrus, however, only 30% exhibited face-selective activation in the right FFA, as defined by the TD group. (C,D) There were no group differences in the extent (total number of active voxels) or magnitude of face selectivity (difference in beta weights for faces and objects from the individual subject ROI GLMs) in the right or left face-related fusiform gyrus ROIs. (E) Eighty percent of the TD individuals exhibited face-selective activation in the right OFA, with 70% overlapping in the TD group-defined OFA ROI. (F) Although 100% of the HFA participants exhibited face-selective activation in the right OFA, only 30% exhibited overlapping activation in the OFA as defined by the TD group. (G,H) There were no group differences in the size or magnitude of face selectivity in the individually defined OFA ROIs, however, the TD individuals tended to exhibit more activation across both visual categories in the right and left OFA.
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Figure 3: Individual subject variability in location, size, and magnitude of face-selective activation in the fusiform gyrus (A–D) and OFA (E–H). The individually defined face contrast map for each participant in each group, represented in a unique color, was thresholded using the FDR procedure (q < 0.10) and overlaid onto a single inflated brain. The respective group-defined ROIs are illustrated in white. (A) Ninety percent of the TD individuals exhibited face-selective activation in the right fusiform gyrus, with 60% in the TD group-defined right FFA ROI. (B) In contrast, 70% of the HFA exhibited face-selective activation in the right fusiform gyrus, however, only 30% exhibited face-selective activation in the right FFA, as defined by the TD group. (C,D) There were no group differences in the extent (total number of active voxels) or magnitude of face selectivity (difference in beta weights for faces and objects from the individual subject ROI GLMs) in the right or left face-related fusiform gyrus ROIs. (E) Eighty percent of the TD individuals exhibited face-selective activation in the right OFA, with 70% overlapping in the TD group-defined OFA ROI. (F) Although 100% of the HFA participants exhibited face-selective activation in the right OFA, only 30% exhibited overlapping activation in the OFA as defined by the TD group. (G,H) There were no group differences in the size or magnitude of face selectivity in the individually defined OFA ROIs, however, the TD individuals tended to exhibit more activation across both visual categories in the right and left OFA.

Mentions: To illustrate individual variability within the HFA and TD groups in the location and size/extent of face-related ROIs, composite maps were created that show face-related activation defined uniquely for each individual in the FG (Figures 3A,B) and OFA (Figures 3E,F). In the composite maps, each participant's individually defined face-selective activation is shown in a unique color with the group-defined face-selective FG and OFA activation illustrated in white (see Table S3 in Supplementary Material for coordinates and size of individual ROIs). Ninety percent of the individuals in the TD group exhibited face-selective activation in the right FG, with 60% exhibiting face-selective activation in the TD group-defined right FFA ROI. In contrast, 70% of the individuals in the HFA group exhibited face-selective activation in the right FG, however, only 30% of the HFA individuals exhibited face-selective activation in the right FFA, as defined by the TD group. Similarly, 80% of the TD individuals exhibited face-selective activation in the right OFA, with 70% overlapping in the TD group-defined OFA ROI. Although 100% of the HFA participants exhibited face-selective activation in the right OFA, only 30% of these individuals exhibited overlapping activation in the OFA as defined by the TD group. These results indicate that 20% fewer individuals within the HFA group exhibited identifiable face-selective activation in the FG, even at the somewhat lenient statistical threshold of FDR q < 0.10, and 50% fewer exhibited such activation in the FFA region of the FG. Furthermore, when this face-selective activation can be identified, there is considerably more variability in the location of both the FG and OFA face-selective ROIs among the individuals with autism.


Location, Location, Location: Alterations in the Functional Topography of Face- but not Object- or Place-Related Cortex in Adolescents with Autism.

Scherf KS, Luna B, Minshew N, Behrmann M - Front Hum Neurosci (2010)

Individual subject variability in location, size, and magnitude of face-selective activation in the fusiform gyrus (A–D) and OFA (E–H). The individually defined face contrast map for each participant in each group, represented in a unique color, was thresholded using the FDR procedure (q < 0.10) and overlaid onto a single inflated brain. The respective group-defined ROIs are illustrated in white. (A) Ninety percent of the TD individuals exhibited face-selective activation in the right fusiform gyrus, with 60% in the TD group-defined right FFA ROI. (B) In contrast, 70% of the HFA exhibited face-selective activation in the right fusiform gyrus, however, only 30% exhibited face-selective activation in the right FFA, as defined by the TD group. (C,D) There were no group differences in the extent (total number of active voxels) or magnitude of face selectivity (difference in beta weights for faces and objects from the individual subject ROI GLMs) in the right or left face-related fusiform gyrus ROIs. (E) Eighty percent of the TD individuals exhibited face-selective activation in the right OFA, with 70% overlapping in the TD group-defined OFA ROI. (F) Although 100% of the HFA participants exhibited face-selective activation in the right OFA, only 30% exhibited overlapping activation in the OFA as defined by the TD group. (G,H) There were no group differences in the size or magnitude of face selectivity in the individually defined OFA ROIs, however, the TD individuals tended to exhibit more activation across both visual categories in the right and left OFA.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC2904054&req=5

Figure 3: Individual subject variability in location, size, and magnitude of face-selective activation in the fusiform gyrus (A–D) and OFA (E–H). The individually defined face contrast map for each participant in each group, represented in a unique color, was thresholded using the FDR procedure (q < 0.10) and overlaid onto a single inflated brain. The respective group-defined ROIs are illustrated in white. (A) Ninety percent of the TD individuals exhibited face-selective activation in the right fusiform gyrus, with 60% in the TD group-defined right FFA ROI. (B) In contrast, 70% of the HFA exhibited face-selective activation in the right fusiform gyrus, however, only 30% exhibited face-selective activation in the right FFA, as defined by the TD group. (C,D) There were no group differences in the extent (total number of active voxels) or magnitude of face selectivity (difference in beta weights for faces and objects from the individual subject ROI GLMs) in the right or left face-related fusiform gyrus ROIs. (E) Eighty percent of the TD individuals exhibited face-selective activation in the right OFA, with 70% overlapping in the TD group-defined OFA ROI. (F) Although 100% of the HFA participants exhibited face-selective activation in the right OFA, only 30% exhibited overlapping activation in the OFA as defined by the TD group. (G,H) There were no group differences in the size or magnitude of face selectivity in the individually defined OFA ROIs, however, the TD individuals tended to exhibit more activation across both visual categories in the right and left OFA.
Mentions: To illustrate individual variability within the HFA and TD groups in the location and size/extent of face-related ROIs, composite maps were created that show face-related activation defined uniquely for each individual in the FG (Figures 3A,B) and OFA (Figures 3E,F). In the composite maps, each participant's individually defined face-selective activation is shown in a unique color with the group-defined face-selective FG and OFA activation illustrated in white (see Table S3 in Supplementary Material for coordinates and size of individual ROIs). Ninety percent of the individuals in the TD group exhibited face-selective activation in the right FG, with 60% exhibiting face-selective activation in the TD group-defined right FFA ROI. In contrast, 70% of the individuals in the HFA group exhibited face-selective activation in the right FG, however, only 30% of the HFA individuals exhibited face-selective activation in the right FFA, as defined by the TD group. Similarly, 80% of the TD individuals exhibited face-selective activation in the right OFA, with 70% overlapping in the TD group-defined OFA ROI. Although 100% of the HFA participants exhibited face-selective activation in the right OFA, only 30% of these individuals exhibited overlapping activation in the OFA as defined by the TD group. These results indicate that 20% fewer individuals within the HFA group exhibited identifiable face-selective activation in the FG, even at the somewhat lenient statistical threshold of FDR q < 0.10, and 50% fewer exhibited such activation in the FFA region of the FG. Furthermore, when this face-selective activation can be identified, there is considerably more variability in the location of both the FG and OFA face-selective ROIs among the individuals with autism.

Bottom Line: With these data, we mapped the functional topography of category-selective activation for faces bilaterally in the fusiform gyrus, occipital face area, and posterior superior temporal sulcus.Additionally, we mapped category-selective activation for objects in the lateral occipital area and for places in the parahippocampal place area in the two groups.Our findings do not indicate a generalized disruption in the development of the entire ventral visual pathway in autism.

View Article: PubMed Central - PubMed

Affiliation: Cognitive Neuroscience Laboratory, Department of Psychology, Center for the Neural Basis of Cognition, Carnegie Mellon University Pittsburgh, PA, USA.

ABSTRACT
In autism, impairments in face processing are a relatively recent discovery, but have quickly become a widely accepted aspect of the behavioral profile. Only a handful of studies have investigated potential atypicalities in autism in the development of the neural substrates mediating face processing. High-functioning individuals with autism (HFA) and matched typically developing (TD) controls watched dynamic movie vignettes of faces, common objects, buildings, and scenes of navigation while undergoing an fMRI scan. With these data, we mapped the functional topography of category-selective activation for faces bilaterally in the fusiform gyrus, occipital face area, and posterior superior temporal sulcus. Additionally, we mapped category-selective activation for objects in the lateral occipital area and for places in the parahippocampal place area in the two groups. Our findings do not indicate a generalized disruption in the development of the entire ventral visual pathway in autism. Instead, our results suggest that the functional topography of face-related cortex is selectively disrupted in autism and that this alteration is present in early adolescence. Furthermore, for those HFA adolescents who do exhibit face-selective activation, this activation tends to be located in traditionally object-related regions, which supports the hypothesis that perceptual processing of faces in autism may be more akin to the perceptual processing of common objects in TD individuals.

No MeSH data available.


Related in: MedlinePlus