It’s been six years since researchers reported the eye-opening discovery that the pupils of children with autism constrict unusually slowly in response to light. The finding raised the intriguing possibility that eyes could act as a window into autism risk, or a biomarker for the disorder. A new study published 3 March in Molecular Autism nudges this possibility closer to reality. It reports that infants who have a sibling with autism — and therefore a 20-fold increased riskfor the disorder themselves — have an altered pupil reflex. But here’s the rub: Unlike the slow pupil reflex seen in children with autism, the reflex in these so-called ‘baby sibs’ is unusually fast.
Read more here.