Breakthrough research from the University of Bath found adults with epilepsy have higher traits of autism and Asperger syndrome.
It found epileptic seizures disrupt the neurological function that affects social functioning in brains, resulting in the same traits seen in autism.
These characteristics include impairment in social interaction and communication as well as restricted and repetitive interests.
SallyAnn Wakeford, a PhD student at the university's Department of Psychology, said the traits could be "severe" and go unnoticed for many years, having a great impact on the lives of those experiencing them.
She said: "Epilepsy has a history of cultural stigma, however the more we understand about the psychological consequences of epilepsy the more we can remove the stigma and mystique of this condition."