This study aims to find out the incidence of a reduced light adapted electroretinogram (ERG) b-wave amplitude in children with a diagnosis of Autism Spectrum Disorders (ASD).

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

individuals diagnosed with ASD and typically developing controls