Doctors often conflate autism and intellectual disability, and no wonder: The biological distinction between them is murky. Scientific progress depends on knowing where the conditions intersect — and part ways.

Most autistic people want to and can make friends, though their relationships often have a distinctive air.

For many autistic adults, the golden years are tarnished by poor health, poverty and, in some cases, homelessness. Their plight reveals huge gaps in care.

Autistic adults have more job opportunities than they used to, and a small neurodiverse workforce is thriving — but mainly at select companies that invest heavily in such employees.

Aripiprazole, marketed as Abilify, is widely thought to be safer than risperidone, the only other drug approved for use in autistic children. A decade’s worth of data suggests that is not true.

Many people with autism experience a triad of trauma: neglect at home, abuse from trusted adults and bullying at school or work.

Some scientists say an immune condition called PANDAS affects as many as 1 in 200 children who have traits similar to those of autism. But many experts contest that figure — and even the condition’s very existence.

Autistic people have long maintained that repetitive behaviors are beneficial. Emerging evidence in support of this idea is shaping new therapies.

This is part 1 of the story of one boy’s long journey to an autism diagnosis and therapy. Part 2 will track Owen’s progress later this year.

Cardiac activity could reveal autism’s physiology and confirm a hunch many clinicians share: that people with autism experience great stress.