What causes ADHD?
The exact cause is unknown but the condition has been shown to run in families. Genetics are involved with one-third of those with ADHD having at least one parent with similar symptoms. Research has also identified several possible differences in the brains of people with ADHD when compared with those without the condition.
Other potential factors include:
Being born prematurely before the 37th week of pregnancy
Having a low birth weight
Smoking, or alcohol or drug abuse during pregnancy.
ADHD can occur in people of any intellectual ability, although it's more common in people with learning difficulties.