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Autism and Link with Vision

 

Autism Spectrum Disorder (ASD), affects about 1-2% of the population (over 25 million globally).  It is a neurodevelopmental condition characterized by difficulties with social interactions, communication and behaviour.

Like many multifactorial conditions autism is associated with a combination of genetic and environmental factors such as infections during pregnancy or exposure to various toxins. Whilst we do not know the exact mechanism of ASD we know it affects brain processing by altering the connections and organization of the nerve cells in the brain.

The most well-known subtype of ASD is Aspergers Syndrome (often referred to as a much higher functioning form of autism that has a later onset). We do know that early intervention and management are vital to maximize the quality of life and outcomes for the individual.

Visual Impact of ASD

Many studies in ASD have shown that these individuals “see” and process the world around them differently. A comprehensive review of the visual function of children with autism has revealed that they have normal visual acuity but there is an increased likelihood of astigmatism, strabismus (turned eyes) and retinal structure and function may be compromised. Neurologically, they exhibit atypical eye movements, have visual-motor deficits and have difficulty with attention, crowding and task complexity so that visual processing at various levels is also reduced.

Avoiding Eye Contact

Children with autism will generally avoid eye contact, often stare at spinning objects or only give fleeting peripheral glances at an object or person of interest. This is thought to contribute to the abnormal development of the social brain. There is a difficulty in coordinating their central and peripheral vision and frequently rely on a constant scanning of their visual surroundings in an attempt to gain information.

Recent studies have shown that the difficulty autistic individuals have in looking into other people’s eyes is not due to lack of concern but because it is very stressful for them, some even saying that “it burns”. Using Functional MRI (which measures brain activity by detecting changes associated with blood flow), researchers have discovered that the behaviour of not looking into people’s eyes is a result of excessive “arousal stemming from over -activation in a particular part of the brain” due to an imbalance between the brain’s excitatory and inhibitory signalling networks.

It is important that one does not force children with autism to look into someone’s eyes as it creates a lot of anxiety. Rather, slow familiarization to eye contact may help the child overcome this overreaction.

What Can Be Done

In addition to the standard eye test, it is vital that your optometrist evaluate the child’s ability to organize visual space, gain peripheral stability, attend to their central vision, ensure there is sufficient visual-motor coordination and appropriate levels of visual information processing. Ensuring that the child is able to visually evaluate their environment will ensure they feel less overwhelmed by visual stimuli and can interact with the world around them more easily.

References:

Chaste P, Leboyer M (2012). “Autism risk factors: genes, environment, and gene-environment interactions”. Dialogues in Clinical Neuroscience. 14 (3): 281–92

https://www.covd.org/page/Autism

Little JA. Vision in children with autism spectrum disorder: a critical review. Clin Exp Optom. 2018 Jul;101(4):504-513. doi: 10.1111/cxo.12651. Epub 2018 Jan 11.

Thomas W. Frazier, Eric W. Klingemier, Mary Beukemann, Leslie Speer, Leslie Markowitz, Sumit Parikh, Steven Wexberg, Kimberly Giuliano, Elaine Schulte, Carol Delahunty, Veena Ahuja, Charis Eng, Michael J. Manos, Antonio Y. Hardan, Eric A. Youngstrom, Mark S. Strauss. Development of an Objective Autism Risk Index Using Remote Eye Tracking. Journal of the American Academy of Child & Adolescent Psychiatry, 2016; 55 (4): 301 DOI: 10.1016/j.jaac.2016.01.011

Nouchine Hadjikhani, Jakob Åsberg Johnels, Nicole R. Zürcher, Amandine Lassalle, Quentin Guillon, Loyse Hippolyte, Eva Billstedt, Noreen Ward, Eric Lemonnier, Christopher Gillberg. Look me in the eyes: constraining gaze in the eye-region provokes abnormally high subcortical activation in autism. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-03378-5

By Arthur Stevens, Director and Optometrist at Kosmac & Clemens Optometrists.