For the study, which was published July 12 in the European Journal of Neuroscience, researchers tracked the eye movements of patients with ASD. Participants were asked to follow a visual target that appeared in different locations on the screen. The experiment was designed to cause the participants’ focus to “overshoot” the intended target.
Eye movements and the mechanisms by which the brain controls what we choose to look at have been a focal point of neuroscience research for years. The rapid eye movements (REMs) we make when shifting attention from one object to another, known as saccades, play a crucial role in our ability to navigate and interact with the world around us.
The study found that in healthy patients, the saccades were found to automatically correct as the task was repeated. However, the saccades of individuals with ASD continued to miss the target, suggesting that the sensory motor controls in the cerebellum responsible for eye movement were impaired, according to the researchers.
“These findings build upon a growing field of research that show that eye movement could serve as a window into a part of the brain that plays a role in a number of neurological and developmental disorders, such as Autism,” said John Foxe, Ph.D., director of the University of Rochester Medical Center Del Monte Neuroscience Institute and co-author of the study.
Autism spectrum disorders are characterized by a wide range of symptoms that can vary significantly from patient to patient. This makes diagnosis and treatment difficult, which is why identifying the specific phenotype of the disorder is a crucial first step to providing effective care, according to the researchers.
“Assessing the ability of people to adapt saccade amplitudes is one way to determine whether this function of the cerebellum is altered in ASD,” said Edward Freedman, Ph.D. an associate professor in the URMC Department of Neuroscience and co-author of the study. “If these deficits do turn out to be a consistent finding in a sub-group of children with ASD, this raises the possibility that saccade adaptation measures may have utility as a method that will allow early detection of this disorder.”
Source: Science Daily