Currently, 1 in 59 children are diagnosed with Autism Spectrum Disorder (ASD)1. Children with ASD rely more on visual input for balance compared to typically-developing (TD) children2-3, but balance assessment is not part of the standard diagnostic process. Under challenging conditions (e.g., quiet standing with eyes closed), children with ASD have higher sway4-5. Given the critical role of static and dynamic postural control as building blocks to higher-order skills, we aimed to identify differences between ASD and TD. We hypothesized that individuals with ASD would have lower postural control than TD individuals, especially when visual context was impaired or visuomotor integration was required.
60 individuals participated in this study, 30 with ASD (M = 23, F = 7), and 30 TD (M = 16, F = 14). Participants were aged 7-36; groups did not differ in mean age (p [greater than] 0.05). The ASD group had a mean age of 13.77 (SD = 5.89) and the TD group had a mean age of 13.83 (SD = 6.26). We conducted this study in community locations using portable eye-tracking and balance-testing systems to administer the Clinical Test of Sensory Integration in Balance (CTSIB; static) and a Limits of Stability task (LOS; dynamic). The CTSIB had 3 conditions: eyes open, eyes closed, and eyes open with visual context removed. The LOS task had 8 eccentric targets.
Individuals with ASD showed increased sway during the CTSIB task in comparison to TD. During the LOS task, individuals with ASD demonstrated decreased postural control and increased time to complete task when compared to Individuals of TD. Individuals with ASD also demonstrated increased saccades, fixations and blinks throughout each task compared to TD participants.
The CTSIB and LOS tasks yielded lower static and dynamic postural stability in the ASD group. For the LOS task, this led to a longer time-to-complete for the ASD group. The eye movements of individuals with ASD were also not optimal for efficient intake of visual information. Visual information may play a larger role in sensorimotor control for ASD than TD individuals than previously suspected. Balance testing and intervention is not provided in most clinics and educational settings serving individuals with ASD, but given the level of impairment observed in our study and others, it may be warranted for individuals who struggle with motor control.||