It’s often said that ‘the eyes tell it all’ but now according to new research from Flinders University and the University of South Australia, the eyes may also be able to signal neurodevelopmental disorders such as ASD and ADHD.
As part of the study, researchers found that recordings from the retina could identify distinct signals for both Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD) providing a potential biomarker for each condition.
Using the ‘electroretinogram’ (ERG) – a diagnostic test that measures the electrical activity of the retina in response to a light stimulus – researchers found that children with ADHD showed higher overall ERG energy, whereas children with ASD showed less ERG energy.
Research optometrist at Flinders University, Dr Paul Constable, says the preliminary findings indicate promising results for improved diagnosis and treatment in the future.
“ASD and ADHD are the most common neurodevelopmental disorders diagnosed in childhood. But as they often share similar traits, this means diagnosis for both conditions can be lengthy and complicated,” says Dr Constable.
Dr Constable says that this research aims to improve the diagnosis process for these conditions. This, he says, will be done through the exploration of how the retina react to light stimuli.
“By exploring how signals in the retina react to light stimuli, we hope to develop more accurate and earlier diagnoses for different neurodevelopmental conditions,” he says.
“Retinal signals have specific nerves that generate them, so if we can identify these differences and localise them to specific pathways that use different chemical signals that are also used in the brain, then we can show distinct differences for children with ADHD and ASD and potentially other neurodevelopmental conditions.”
Dr Constable says that this study “delivers preliminary evidence for neurophysiological changes that not only differentiate both ADHD and ASD from typically developing children, but also evidence that they can be distinguished from each other based on ERG characteristics.”
Co-researcher and expert in human and artificial cognition at the University of South Australia, Dr Fernando Marmolejo-Ramos, says the research has the potential to extend across other neurological conditions.
“Ultimately, we’re looking at how the eyes can help us understand the brain,” says Dr Marmolejo-Ramos.
“While further research is needed to establish abnormalities in retinal signals that are specific to these and other neurodevelopmental disorders, what we’ve observed so far shows that we are on the precipice of something amazing.
“It is truly a case of watching this space; as it happens, the eyes could reveal all.”
