Short-Duration Visual Evoked Potentials (VEPs) in Children with ASD

Background: Previous studies have demonstrated visual deficits in children with autism spectrum disorder (ASD). However, there is a paucity of data on early-stage visual processing in this population. Children with ASD are often difficult to assess on visual tasks, which is reflected by studies that generally target higher functioning children. Visual evoked potentials (VEPs) provide noninvasive, rapid, and reliable measures of neural functions, and therefore, they may eventually be used to identify neural dysfunction, changes in visual processing over time, and to serve as biomarkers for subgroups of children with ASD. Before this advancement in assessment can be achieved, VEP techniques must be modified to facilitate collection of data on children at various levels of functioning.

Objectives: To determine whether a battery of short-duration stimulation and analysis conditions will adequately probe select pathways and mechanisms within the brains of children with ASD and typically developing children.

Methods: Transient and steady-state VEP recordings were obtained from 5 children with ASD and 12 typically developing children using the Neucodia system (VeriSci Corp.). Short-duration stimuli were 3 seconds in duration with 1 second for adaptation and 2 seconds for data collection. Each condition was comprised of 10 runs and synchronized data collection was used. Short-duration recordings were compared to long-duration (60-s) recordings. Visual acuity was measured and ASD diagnoses were determined using the Autism Diagnostic Observation Schedule (ADOS).

Results: Findings demonstrate that short-duration stimuli, in conjunction with statistical analysis of the brain’s responses, can yield sensitive and objective indices of the neural pathways under investigation.

Conclusions: Short-duration (2-s) epochs may be used in place of long-duration (60-s) epochs in order to record VEP responses in children with and without ASD. Short duration stimuli allow for faster data collection while applying rigorous methods for statistical significance. Future studies may apply short-duration VEP techniques to examine underlying neural mechanisms in the visual systems of children with ASD.