Atypical pupillary light reflex in 2-6-year-old children with autism spectrum disorders

Area of Science:

• Neurodevelopmental Disorders
• Autonomic Nervous System Function
• Ophthalmology

Background:

• Autism Spectrum Disorder (ASD) is a neurodevelopmental condition affecting social interaction and communication.
• Autonomic Nervous System (ANS) dysfunction is frequently observed in individuals with ASD.
• Pupillary Light Reflex (PLR) is a sensitive indicator of ANS activity.

Purpose of the Study:

• To investigate pupillary light reflex (PLR) parameters in young children (2-6 years) diagnosed with Autism Spectrum Disorder (ASD).
• To compare PLR and autonomic nervous system (ANS) related symptoms between children with ASD and typically developing (TD) children.
• To explore the association between PLR parameters and ANS dysfunction in both groups.

Main Methods:

• Study included 117 medication-free boys aged 2-6 years, divided into an ASD group (n=60) and a TD group (n=57).
• Parents/guardians completed questionnaires assessing potential ANS dysfunctions.
• Pupil size, PLR latency, and constriction time were measured and analyzed for age-related trends and group differences.

Main Results:

• Significant age-related trends in base pupil radius, PLR latency, and constriction time were observed in both ASD and TD groups.
• Base pupil size increased with age in TD children, but not in children with ASD.
• The ASD group reported more ANS dysfunction symptoms, and the association between PLR parameters and ANS dysfunction differed between groups.

Conclusions:

• Children with ASD exhibit distinct patterns in pupillary light reflex compared to typically developing children.
• Differences in PLR parameters and their association with ANS dysfunction suggest disrupted autonomic control mechanisms in young children with ASD.
• Further research into ANS regulation is warranted for understanding and supporting individuals with ASD.