The brainstem’s white matter — the nerve fibers that connect brain regions — may be altered in autistic people. Among boys and men with autism, those with more poorly organized white matter in the brainstem also have more severe autism traits and weaker grip strength, hinting at a link between the brainstem and motor problems …
The severity of autism tracks closely with that of attention deficit hyperactivity disorder (ADHD), and the brainstem may underlie this connection: Children with either condition who have a small brainstem tend to have severe traits.
Children with autism show different patterns of connectivity than controls do in brain stem regions associated with balance. The connections in the brain stem are associated with balance and motor skills, both of which are known to be frequently affected in autism.
