Abnormal Transient Pupillary Light Reflex in Individuals with Autism Spectrum Disorders

Abstract

Computerized binocular infrared pupillography was used to measure the transient pupillary light reflex (PLR) in both children with autism spectrum disorders (ASDs) and children with typical development. We found that participants with ASDs showed significantly longer PLR latency, smaller constriction amplitude and lower constriction velocity than children with typical development. The PLR latency alone can be used to discriminate the ASD group from the control group with a cross-validated success rate of 89.6%. By adding the constriction amplitude, the percentage of correct classification can be further improved to 92.5%. In addition, the right-lateralization of contraction anisocoria that was observed in participants with typical development was not observed in those with ASDs. Further studies are necessary to understand the origin and implications of these observations. It is anticipated that as potential biomarkers, these pupillary light reflex measurements will advance our understanding of neurodevelopmental differences in the autism brain.

Quantitative Assessment of the Canine Pupillary Light Reflex

“…In addition, the PLRs observed in anesthetized dogs were very similar to those recorded in people who were not chemically restrained. 31 Under the conditions of this investigation, chemical restraint using isoflurane did not appear to significantly alter the canine PLR.…”

“…The kinetics of these responses are similar to those of PLRs recorded in people using a similar system. 31 The PIPR was detectable with a stimulus of 11 log photons/ cm 2 /s and increased with each subsequent increase in stimulus intensity (Table 3).…”

Precise minds in uncertain worlds: Predictive coding in autism.

“…Raised NE signaling in ASD is suggested by elevated blood plasma levels (Lam et al, 2006) and by a tonically high arousal system as shown by a tonically elevated heart rate in autistic children, with reduced phasic response (Kootz & Cohen, 1981). For pupil size the same pattern has been reported: increased tonic pupil size and increased latency, smaller constric tion amplitude, and lower constriction velocity for the pupillary light reflex compared to TD children (Anderson & Colombo, 2009;Fan, Miles, Takahashi, & Yao, 2009). This is noteworthy, because of the known coupling of pupil size with the NE system, more specifically with activity in the principal source of NE projections, the locus coeruleus (Rajkowski, Kubiak, & AstonJones, 1993).…”

Sensory Responsiveness as a Predictor of Social Severity in Children with High Functioning Autism Spectrum Disorders

“…Visual motion perception and pursuit eye movement deficits have been reported in individuals with autism (Takarae et al 2008). Increased visual acuity (Ashwin et al 2009) and prolonged pupillary light reflex latency, smaller constriction amplitude, and lower constriction velocity (Fan et al 2009) have been observed in individuals with ASD in comparison to a control group. Each of these findings could help to explain the atypical visual responsiveness sometimes seen in children with ASD.…”