New research published in the UK has found that autism is far more widespread than previously thought.
The finding comes as the world marks the UN-backed Autism Awareness Day.
Researchers hope the day will make people around the world consider donating their brains after death, as there is a desperate need for brain tissue to allow scientists to learn more about the origins of the disease.
Al Jazeera's Simon McGregor-Wood reports from London.
Source: Al Jazeera