Epilepsy is common in children with autism spectrum disorders (ASD). A new study indicates their epilepsy is surprisingly photosensitive as well. Since photosensitive epilepsies can be triggered by flickering lights, the self-stimulatory behavior of ASD children, such as hand flapping in front of the face, has the potential to dramatically increase the risk of inducing photosensitive seizures.
Photosensitivity in children with epilepsy alone is reported to range from 2 - 14%. A pilot study to determine the incidence of photosensitivity in children with ASD has found a significant and unexpected higher rate of nearly 30% photosensitivity in adolescents with epilepsy and autism comorbidity. (Abstract 3.109) The study, presented at the American Epilepsy Society's 65th annual meeting, is the first report of this marked difference in response to intermittent photic stimulation.
Investigators at Children's Hospital Boston reviewed the records of children diagnosed with ASD between December 2010 and May 2011. Those given an EEG prior to or during the search period were included in the study. The EEG reports were examined to determine the presence or absence of a photoparoxysmal response (PPR) to intermittent photic stimulation.
"Our study found a high overall incidence of photosensitivity in 25 percent of children over 15 years of age with autism spectrum disorder, and an even higher rate of 29.4 percent in that age group of children who had both epilepsy and autism," says lead author Jill Miller-Horn. "This finding has not been previously reported."
Dr. Miller-Horn noted the relatively small size of the study. "Larger scale prospective studies are needed to confirm this trend," she said. "Further study is also needed to identify the importance of these findings in the pathophysiology of epilepsy in children with autism spectrum disorder."