title: Low-contrast response deficits and increased neural noise in children with autism spectrum disorder.
abstract: A battery of short-duration neurophysiological tests were designed and implemented using visual evoked potentials (VEPs) to examine specific neural mechanisms in children with and without autism spectrum disorder (ASD). Contrast-sweep conditions (bright or dark isolated-checks) were used to elicit steady-state VEPs to examine the integrity of ON/OFF pathways. Children with ASD displayed deficits in low-contrast responses at the stimulus frequency of 12.5 Hz, notably under conditions that emphasized activity in the magnocellular pathway. Signal-to-noise ratios were weaker in the ASD group, particularly for the OFF pathway. There were no group differences in the amplitude of responses. In addition, the ASD group displayed significantly higher levels of neural noise than controls. For the response at the stimulus frequency, the ASD group produced a relatively constant level of noise across the contrast range tested, with higher levels than controls at low contrasts and approximately equal levels of noise at moderate to high contrasts.
authors.affiliation: Icahn School of Medicine at Mount Sinai Seaver Autism Center, Psychiatry One Gustave Levy Place, Box 1230 Atran Building E Level, Room 22, New York, NY 10029, United States. Electronic address: paige.weinger@mssm.edu.
authors.forename: Paige M
authors.initials: PM
authors.lastname: Weinger
authors.affiliation: Yeshiva University, New York, United States.
authors.forename: Vance
authors.initials: V
authors.lastname: Zemon
authors.affiliation: Rush University Medical Center, Chicago, Illinois, United States.
authors.forename: Latha
authors.initials: L
authors.lastname: Soorya
authors.affiliation: Hunter College, New York, United States.
authors.forename: James
authors.initials: J
authors.lastname: Gordon
mesh_terms: D002648:Child; D002659:Child Development Disorders, Pervasive / Q000503:physiopathology*; D015350:Contrast Sensitivity / Q000502:physiology*; D004569:Electroencephalography; D005074:Evoked Potentials, Visual; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D059629:Signal-To-Noise Ratio; D014793:Visual Cortex / Q000503:physiopathology*; D014795:Visual Pathways / Q000503:physiopathology*
keywords: Autism spectrum disorder; Early-stage visual processing; Neural noise; ON and OFF pathways; Visual evoked potential