Slower Rate of Binocular Rivalry in Autism

• Published in: The Journal of neuroscience Vol. 33; no. 43; pp. 16983 - 16991
• Main Authors: Robertson, Caroline E., Kravitz, Dwight J., Freyberg, Jan, Baron-Cohen, Simon, Baker, Chris I.
• Format: Journal Article
• Language: English
• Published: United States Society for Neuroscience 23.10.2013
• Subjects: Adult; Autistic Disorder - physiopathology; Brassica; Case-Control Studies; Female; Humans; Male; Middle Aged; Reaction Time; Vision, Binocular; Visual Cortex - physiopathology; Visual Perception
• ISSN: 0270-6474; 1529-2401; 1529-2401
• DOI: 10.1523/JNEUROSCI.0448-13.2013

An imbalance between cortical excitation and inhibition is a central component of many models of autistic neurobiology. We tested a potential behavioral footprint of this proposed imbalance using binocular rivalry, a visual phenomenon in which perceptual experience is thought to mirror the push and pull of excitatory and inhibitory cortical dynamics. In binocular rivalry, two monocularly presented images compete, leading to a percept that alternates between them. In a series of trials, we presented separate images of objects (e.g., a baseball and a broccoli) to each eye using a mirror stereoscope and asked human participants with autism and matched control subjects to continuously report which object they perceived, or whether they perceived a mixed percept. Individuals with autism demonstrated a slower rate of binocular rivalry alternations than matched control subjects, with longer durations of mixed percepts and an increased likelihood to revert to the previously perceived object when exiting a mixed percept. Critically, each of these findings was highly predictive of clinical measures of autistic symptomatology. Control “playback” experiments demonstrated that differences in neither response latencies nor response criteria could account for the atypical dynamics of binocular rivalry we observed in autistic spectrum conditions. Overall, these results may provide an index of atypical cortical dynamics that may underlie both the social and nonsocial symptoms of autism.