The brains of autistic children show few differences from those of children with attention deficit hyperactivity disorder, or even of controls.

A study of more than 5 million people reveals the onset and prevalence of nine diagnoses that often accompany autism.

Autism may be just as common among children missing a segment of chromosome 16 as it is in those with an extra copy.

An analysis of DNA from more than 20,000 people with autism identifies 12 regions in the genome that harbor inherited risk factors for the condition.

About one in three autistic people in the United Kingdom is prescribed drugs designed to alter brain function.

Children who have an older sibling with attention deficit hyperactivity disorder are at an increased risk of having autism. The reverse is also true.

Traits linked to autism and attention deficit hyperactivity disorder tend to co-occur even in adulthood.

Theory of mind difficulties are likely to be more central to autism than to attention deficit hyperactive disorder, whereas executive function problems are more often associated with the latter.

The number of children diagnosed with attention deficit hyperactivity disorder (ADHD) has reached more than 10 percent, a significant increase during the past 20 years, according to a new study.

Many people with autism entertain thoughts of suicide and yet show few obvious signs of their distress. Some scientists are identifying risks — and solutions — unique to autistic individuals.