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Stronger Neural Modulation by Visual Motion Intensity in Autism Spectrum Disorders.

Peiker I, Schneider TR, Milne E, Schöttle D, Vogeley K, Münchau A, Schunke O, Siegel M, Engel AK, David N - PLoS ONE (2015)

Bottom Line: A polynomial regression analysis revealed that gamma-band power increased significantly stronger with motion coherence in ASD compared to controls, suggesting excessive visual activation with increasing stimulus intensity originating from motion-responsive visual areas V3, V6 and hMT/V5.Enhanced neural responses with increasing stimulus intensity suggest an enhanced response gain in ASD.Thus, our data suggest that a disturbed excitatory-inhibitory balance underlies enhanced neural responses to coherent motion in ASD.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

ABSTRACT
Theories of autism spectrum disorders (ASD) have focused on altered perceptual integration of sensory features as a possible core deficit. Yet, there is little understanding of the neuronal processing of elementary sensory features in ASD. For typically developed individuals, we previously established a direct link between frequency-specific neural activity and the intensity of a specific sensory feature: Gamma-band activity in the visual cortex increased approximately linearly with the strength of visual motion. Using magnetoencephalography (MEG), we investigated whether in individuals with ASD neural activity reflect the coherence, and thus intensity, of visual motion in a similar fashion. Thirteen adult participants with ASD and 14 control participants performed a motion direction discrimination task with increasing levels of motion coherence. A polynomial regression analysis revealed that gamma-band power increased significantly stronger with motion coherence in ASD compared to controls, suggesting excessive visual activation with increasing stimulus intensity originating from motion-responsive visual areas V3, V6 and hMT/V5. Enhanced neural responses with increasing stimulus intensity suggest an enhanced response gain in ASD. Response gain is controlled by excitatory-inhibitory interactions, which also drive high-frequency oscillations in the gamma-band. Thus, our data suggest that a disturbed excitatory-inhibitory balance underlies enhanced neural responses to coherent motion in ASD.

No MeSH data available.


Related in: MedlinePlus

Functional overlays of linear modulation by visual motion strength.Data were averaged across time points (150–350 ms after stimulus onset) and frequencies (60–80 Hz). Projection on a standard MNI cortical surface was performed by weighting the distance between every voxel in the functional data to each surface point on the cortex. Colors represent positive z-values, while negative z-values are not shown (gray color).
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pone.0132531.g004: Functional overlays of linear modulation by visual motion strength.Data were averaged across time points (150–350 ms after stimulus onset) and frequencies (60–80 Hz). Projection on a standard MNI cortical surface was performed by weighting the distance between every voxel in the functional data to each surface point on the cortex. Colors represent positive z-values, while negative z-values are not shown (gray color).

Mentions: Regression analyses on source level yielded functional maps that depict the cortical distribution of the positive linear modulation of gamma-band activity by visual motion (Fig 4). In both groups, this modulation was primarily located in striate and extrastriate visual areas, with a more widespread cortical distribution in the control group. The standardized difference (z-values, uncorrected) between groups suggests that the enhanced stimulus-related gamma-band modulation in ASD originated specifically from extrastriate brain areas. The location of the effect was anatomically compatible with previously reported activation for coherent motion in visual areas V3/ V6 (here in both hemispheres) and hMT/V5 (here in the right hemisphere; Fig 4) [53].


Stronger Neural Modulation by Visual Motion Intensity in Autism Spectrum Disorders.

Peiker I, Schneider TR, Milne E, Schöttle D, Vogeley K, Münchau A, Schunke O, Siegel M, Engel AK, David N - PLoS ONE (2015)

Functional overlays of linear modulation by visual motion strength.Data were averaged across time points (150–350 ms after stimulus onset) and frequencies (60–80 Hz). Projection on a standard MNI cortical surface was performed by weighting the distance between every voxel in the functional data to each surface point on the cortex. Colors represent positive z-values, while negative z-values are not shown (gray color).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492621&req=5

pone.0132531.g004: Functional overlays of linear modulation by visual motion strength.Data were averaged across time points (150–350 ms after stimulus onset) and frequencies (60–80 Hz). Projection on a standard MNI cortical surface was performed by weighting the distance between every voxel in the functional data to each surface point on the cortex. Colors represent positive z-values, while negative z-values are not shown (gray color).
Mentions: Regression analyses on source level yielded functional maps that depict the cortical distribution of the positive linear modulation of gamma-band activity by visual motion (Fig 4). In both groups, this modulation was primarily located in striate and extrastriate visual areas, with a more widespread cortical distribution in the control group. The standardized difference (z-values, uncorrected) between groups suggests that the enhanced stimulus-related gamma-band modulation in ASD originated specifically from extrastriate brain areas. The location of the effect was anatomically compatible with previously reported activation for coherent motion in visual areas V3/ V6 (here in both hemispheres) and hMT/V5 (here in the right hemisphere; Fig 4) [53].

Bottom Line: A polynomial regression analysis revealed that gamma-band power increased significantly stronger with motion coherence in ASD compared to controls, suggesting excessive visual activation with increasing stimulus intensity originating from motion-responsive visual areas V3, V6 and hMT/V5.Enhanced neural responses with increasing stimulus intensity suggest an enhanced response gain in ASD.Thus, our data suggest that a disturbed excitatory-inhibitory balance underlies enhanced neural responses to coherent motion in ASD.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

ABSTRACT
Theories of autism spectrum disorders (ASD) have focused on altered perceptual integration of sensory features as a possible core deficit. Yet, there is little understanding of the neuronal processing of elementary sensory features in ASD. For typically developed individuals, we previously established a direct link between frequency-specific neural activity and the intensity of a specific sensory feature: Gamma-band activity in the visual cortex increased approximately linearly with the strength of visual motion. Using magnetoencephalography (MEG), we investigated whether in individuals with ASD neural activity reflect the coherence, and thus intensity, of visual motion in a similar fashion. Thirteen adult participants with ASD and 14 control participants performed a motion direction discrimination task with increasing levels of motion coherence. A polynomial regression analysis revealed that gamma-band power increased significantly stronger with motion coherence in ASD compared to controls, suggesting excessive visual activation with increasing stimulus intensity originating from motion-responsive visual areas V3, V6 and hMT/V5. Enhanced neural responses with increasing stimulus intensity suggest an enhanced response gain in ASD. Response gain is controlled by excitatory-inhibitory interactions, which also drive high-frequency oscillations in the gamma-band. Thus, our data suggest that a disturbed excitatory-inhibitory balance underlies enhanced neural responses to coherent motion in ASD.

No MeSH data available.


Related in: MedlinePlus