1. Clery H, Bonnet-Brilhault F, Lenoir P, Barthelemy C, Bruneau N, Gomot M. {{Atypical visual change processing in children with autism: An electrophysiological Study}}. {Psychophysiology};2013 (Jan 14)
Children with Autism Spectrum Disorder (ASD) may display atypical behaviors in reaction to unattended changes that occur in all sensory modalities. Atypical automatic auditory change processing has been highlighted in ASD via the analysis of mismatch negativity (MMN). The present study investigated visual deviancy detection in children with ASD in order to determine whether unusual reactions to change operate in other sensory modalities. Twelve children with ASD were presented with a passive visual oddball paradigm using dynamic stimuli. Compared to controls, children with ASD showed an earlier visual mismatch response, suggesting a hypersensitivity to visual deviancy. This study is thus consistent with the hypothesis of the existence of « general » atypical change detection processing in children with ASD that might contribute to their intolerance of change.
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2. Khan S, Gramfort A, Shetty NR, Kitzbichler MG, Ganesan S, Moran JM, Lee SM, Gabrieli JD, Tager-Flusberg HB, Joseph RM, Herbert MR, Hamalainen MS, Kenet T. {{Local and long-range functional connectivity is reduced in concert in autism spectrum disorders}}. {Proc Natl Acad Sci U S A};2013 (Jan 14)
Long-range cortical functional connectivity is often reduced in autism spectrum disorders (ASD), but the nature of local cortical functional connectivity in ASD has remained elusive. We used magnetoencephalography to measure task-related local functional connectivity, as manifested by coupling between the phase of alpha oscillations and the amplitude of gamma oscillations, in the fusiform face area (FFA) of individuals diagnosed with ASD and typically developing individuals while they viewed neutral faces, emotional faces, and houses. We also measured task-related long-range functional connectivity between the FFA and the rest of the cortex during the same paradigm. In agreement with earlier studies, long-range functional connectivity between the FFA and three distant cortical regions was reduced in the ASD group. However, contrary to the prevailing hypothesis in the field, we found that local functional connectivity within the FFA was also reduced in individuals with ASD when viewing faces. Furthermore, the strength of long-range functional connectivity was directly correlated to the strength of local functional connectivity in both groups; thus, long-range and local connectivity were reduced proportionally in the ASD group. Finally, the magnitude of local functional connectivity correlated with ASD severity, and statistical classification using local and long-range functional connectivity data identified ASD diagnosis with 90% accuracy. These results suggest that failure to entrain neuronal assemblies fully both within and across cortical regions may be characteristic of ASD.
