The part of the nervous system that regulates heart rate and breathing may be involved in autism.

Watch the complete replay of Christine Wu Nordahl discussing new ways to expand participation in autism brain-imaging studies.

Autism is predominantly genetic in origin, but a growing list of prenatal exposures for mother and baby may sway the odds.

Children who have repetitive behaviors, a core autism trait, may show particular patterns of brain activity as early as 1 year of age.

Autistic children aged 2 to 4 have about 15 percent more fluid between their skull and their brain than their typical peers do.

Administering a cholesterol drug alongside an antibiotic eases atypical behavior and restores the signaling balance in the brains of people with fragile X syndrome.

Babies eventually diagnosed with autism learn to detect speech sounds later than their typical peers do.

New and improved autism screens and diagnostic tools promise to streamline the long path to an autism diagnosis.

Children with autism tend to have low levels of the hormone vasopressin in their brain, according to the largest study yet to look at the levels.

People with autism have more gray matter — or neuronal matter — in their brains overall than their typical peers do.