Behavioral and Physiological Changes Due to the Effects of Ambient Prism Lenses and Visuo-Motor Exercises in Autism

Background: A common comorbidity of autism includes a dysfunction within the ambient visual system that negatively affects peripheral vision and causes deficits in attention, hand-eye coordination, balance, and gross motor movement. Ambient vision is necessary for control of anatomical movement involved in spatial orientation and proprioception. Dysfunction of this system impairs the ability to process environmental cues used to control gait, posture, movement, and speech. Loss of spatial orientation negatively affects the vestibular system, which leads to the development of adaptive responses that are consistent with the behavioral symptoms observed in autism.

Objectives: This study uses physiological recordings and clinical surveys to evaluate the effects of corrective ambient prism lenses and daily visuo-motor therapy on aberrant and repetitive behaviors and body coordination.

Methods: In this study, twenty autistic individuals (mean age 12.5) were recruited, evaluated, and individually prescribed corrective ambient prism lenses. Next, a six-month daily vision therapy protocol was implemented. Patients were instructed to wear the corrective ambient prescription lenses all day, except when vision therapy procedures instructed the patients otherwise. Daily vision therapy procedures included exercises that required the patients to wear disruptive prism lenses and occasionally red/green lenses. The combination of the lenses and tasks were used to address problems involved in balance, visual organization, and depth perception. Empirical behavioral data was reported using the Autism Behavior Checklist (ABC) and Repetitive Behavior Scale (RBS). Physiological variables of autonomic reactivity recordings included measurements of Heart Rate (HR), Heart Rate Variability (HRV), Skin Conductance Level (SCL), and Skin Temperature (ST), which were taken while the subject was watching scenes from the classic Disney film, “The Lion King,” to evoke emotional responses.

Results: Autonomic reactivity recordings for Heart Rate Variability (HRV) and Skin Conductance Level (SCL) had significantly decreased after four months of wearing corrective prescription ambient prism lenses compared with baseline recordings showing that sympathetic arousal went down in these individuals. Empirical behavioral data was reported using the Autism Behavior Checklist (ABC) and Repetitive Behavior Scale (RBS). After four months, two out of five scaled scores were significantly reduced according to the ABC. In particular, scores decreased in Irritability (t = 2.97; p = 0.014) and Hyperactivity (t = 3.396; p = 0.007) compared to baseline scores. According to the Repetitive Behavior Scale (RBS), three out of six subscale scores were significantly different. These subscale scores included: Stereotypic Behavior (t = 3.47; p = 0.010), Compulsive Behavior (t = 3.49; p = 0.010) and overall Total Score (t = 2.70; p = 0.031) compared to baseline scores.

Conclusions: Results of this study showed that corrective ambient prism lenses combined with daily visuo-motor therapy reduced autistic behaviors (according to ABC and RBS rating scores) and enhanced autonomic reactivity to emotional stimuli in ASD individuals.