Who wouldn’t love an easy explanation for autism, the heartbreaking brain disorder whose rates have been rising sharply and mysteriously over the past 30 years? History has served up many possibilities, beginning with a now discredited theory put forward by psychologist Bruno Bettelheim, who famously attributed the condition to uncaring “refrigerator moms.” Today autism is thought to involve a genetic vulnerability that’s triggered by an unknown X factor, or factors, in the environment
