Current controversies in the relationships between autism and epilepsy

The controversies that have arisen in endeavoring to establish the nature of the relationships between autism and epilepsy might be summarized in a few simple questions, most of which do not yet have clear, complete answers. Does epilepsy cause autism? Does autism cause epilepsy? Are there underlying brain mechanisms that predispose to both conditions? What is the role of genetics in this regard? What is the importance of prenatal, perinatal, and postnatal environmental factors? Do any of the proposed relationships between autism and epilepsy provide insight into useful management or treatment? Is the prognosis of either autism or epilepsy different when the other condition is also present? What is the role of additional comorbidities, such as intellectual impairment or attention deficit hyperactivity disorder, in the relationship between the two conditions and in influencing treatment choices? From the evidence currently available, it would appear that epilepsy can rarely be the cause of autistic features but is not the cause of autism in most cases. There is currently no credible mechanism for suggesting that autism might cause epilepsy. There is strong evidence for an underlying predisposition for both conditions, particularly arising from genetic investigations. However, many issues remain unresolved. Considering the amount of research that has been published in this area, it is surprising that so few definitive answers have been established. The papers in this issue's special section provide additional insights into the relationships between autism and epilepsy; while they do not provide answers to all the questions, they represent considerable progress in this area and, at the very least, give some strong indication of what research might, in the future, provide such answers.