Biofeedback-Based Balance Training in Autism Spectrum Disorder

Background: Many individuals with autism spectrum disorder (ASD) have difficulties with postural control (for review, see Memari et al., 2014). These postural control difficulties appear to be related to core autism symptom severity (Radonovich et al., 2013; Travers et al., 2013) and may affect adaptive daily living skills, such as dressing and driving. However, there is little published data on whether postural control can be enhanced in ASD through intensive balance training. Examining how balance in ASD changes as a function of training may shed light on the underlying mechanisms involved in poor postural control in ASD and would reveal who on the spectrum may benefit most from this type of training.

Objectives: 1) To examine if substantial balance improvements in ASD can result from a 6-week biofeedback-based balance training, and 2) to examine individual differences in age, cognition, and symptom severity that moderate the effectiveness of the training.

Methods: Twenty-two children and adolescents with ASD (1 female; ages 7-17 years) completed 6 weeks (18 sessions) of biofeedback-based balance training administered through an in-house video game. Each session lasted 60 minutes and consisted of participants playing our Ninja Training game that was developed to promote static balance, using a Kinect camera- and Wii balance board. In this game, each participant viewed him/herself on the screen and was asked to match his/her body to a shadow that portrayed one of six desired balance poses. Participants were rewarded for holding the pose as long as possible. We measured the total length of time that the participant was able to correctly hold each pose. Linear mixed-effects models examined balance-related changes over the course of the 18 training sessions in ASD. Pearson R correlations examined whether individual differences in IQ or symptom severity (SRS and RBS-R) were related to balance training outcomes.

Results: Over the 18 sessions of balance training, participants on average increased their balance times by ~2 seconds each session, exhibiting significant gains for both two-footed, β = 2.25, SE = .50, p < .001, and one-footed standing poses, β = 1.97, SE = .58, p < .001. Higher performance IQ (but not verbal IQ) related to longer starting balance times, r = .50 p = .02, and enhanced training-related gains, r = .41 p < .05. Less severe ritualistic behaviors (but not SRS or other RBS-R domains) related to enhanced training-related gains, r = -.55, p = .008. Age was not significantly related to starting balance times nor training-related gains (all p’s >.08), although the effect sizes were medium (r’s from -.36 to -0.38).

Conclusions: Overall, participants exhibited balance improvements, supporting that balance challenges in ASD can be targeted using biofeedback-based balance training. Surprisingly, age was not a strong predictor of training-related changes. However, individuals with ASD who had higher performance IQs and less frequent ritualistic behaviors demonstrated the largest improvements in balance. These data, while preliminary, shed light on why some individuals with ASD may have more persistent difficulties with balance than others.