title: Stronger Neural Modulation by Visual Motion Intensity in Autism Spectrum Disorders.
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.
authors.affiliation: Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Ina
authors.initials: I
authors.lastname: Peiker
authors.affiliation: Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Till R
authors.initials: TR
authors.lastname: Schneider
authors.affiliation: Clinical Psychology Unit, University of Sheffield, Sheffield, South Yorkshire, United Kingdom.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Milne
authors.affiliation: Department of Psychiatry and Psychotherapy, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Schöttle
authors.affiliation: Department of Psychiatry, University of Cologne, Cologne, Germany; Institute of Neuroscience and Medicine-Cognitive Neurology Section (INM3), Research Center Juelich, Juelich, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Vogeley
authors.affiliation: Department of Pediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Lübeck, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Münchau
authors.affiliation: Department of Pediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Lübeck, Germany; Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Odette
authors.initials: O
authors.lastname: Schunke
authors.affiliation: Centre for Integrative Neuroscience and MEG Center, University of Tübingen, Tübingen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Siegel
authors.affiliation: Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Andreas K
authors.initials: AK
authors.lastname: Engel
authors.affiliation: Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: David
mesh_terms: D000328:Adult; D000067877:Autism Spectrum Disorder / Q000503:physiopathology*; D049690:History, Ancient; D006801:Humans; D008297:Male; D008875:Middle Aged; D009039:Motion Perception; D011597:Psychomotor Performance; D014793:Visual Cortex / Q000503:physiopathology*