Electroretinogram in Autistic Spectrum Disorders

Autism Spectrum Disorder (ASD) is a neurodevelopmental condition which becomes apparent as
children grow. Children with ASD are slow to develop language and have problems interacting
socially with others. It is not clear why ASD occurs, but there is some evidence that the
signals that tell the brain how to grow are altered which causes the brain to develop and
function differently in people with ASD. Eyes develop from the same embryonic tissue as the
brain. This means that the retina, which is the light sensitive layer at the back of the eye,
shares the same signals as the brain. Investigators can listen to retinal signals outside the
eye and the retina can, in this way, act as an accessible part of the brain.

The investigators will detect retinal signals as electrical messages. Sensors placed near the
eye pick up the electrical changes in the retina each time a light flashes. This
non-invasive, routine clinical test is called an electroretinogram, (ERG). The investigators
have carried out a study that showed differences in the ERGs recorded from adults with ASD
compared to control participants.

The main aim of this project is find out how common ERG differences are in children with ASD
compared to controls. If it is common, investigators could use the ERG to make an earlier
diagnosis of ASD and help families sooner. It could help investigators better understand the
way the ASD brain signals and give investigators a way of measuring if therapies work.

Inclusion Criteria:

- cohort 1: individuals with diagnosis ASD with an IQ measure exceeding 85

- cohort 2: typically developed controls without diagnosis of ASD

Exclusion Criteria:

- a history of eye disease or treatment or seizure medicines that may alter retinal
function