Chemicals produced by their mother’s immune system in utero alter the size of several key brain regions in people with schizophrenia, enlarging chambers that store cerebrospinal fluids, and shrinking parts of the cortex involved in processing emotion and memory.

How many people with autism are also obese?

Individuals who carry a large and rare deletion on chromosome 16 that is associated with autism are likely to have developmental delays, be obese or both, according to two studies published last week in Nature.