Background: Motor differences between children with autism spectrum disorders (ASD) and those with typical development (TD) have been identified in various activities such as pointing (Torres et al., 2013) and placing (Crippa et al., 2014). Kinematic differences have also been observed in goal-oriented swipe kinematics during smart-tablet gameplay (Lu et al., 2019, 2020). General Tau Theory has been used to describe goal-oriented perception-action strategies (Lee, 2009), which proposes an intrinsic action guide generated by the nervous system coupled to the motor command to guide the physical movement. The coupling constant between the two is assumed to be set by the brain to coordinate the kinematic profile of the goal-oriented action. Here, an exploration to surface a potential difference in the tau-coupling during smart-tablet gameplay in children with ASD is presented. Objectives: To test whether or not the perception-action strategy employed by children with and without ASD differ during goal-oriented swipes in smart-tablet gameplay. Methods: Goal-oriented swipe data were extracted from a study of smart-tablet gameplay for young children (Anzulewicz et al., 2016). Only those swipes that proceeded directly from start to finish without overshooting the target were included. A total of 500 swipes were obtained from 32 children with ASD (aged 33-79 months), and 1426 swipes were obtained from 44 children with TD (aged 36-74 months). The percentage of tau-coupling in each swipe, its duration and distance, and the tau-coupling constant were determined utilising the time and x- and y-coordinates data. Results: Children with ASD demonstrated 97.90 ± 10.49 (mean ± SD) % while children with TD demonstrated 98.98 ± 7.54 % of tau-coupling movement, indicating a significantly weakening (t-test, p = 0.01) and more variable (F-test, p < 0.01) tau-coupling pattern in children with ASD. The coupling constant was 0.40 ± 0.93 for the ASD group and 0.41 ± 0.15 for the TD group. Children with ASD demonstrated a significantly wider range of the coupling constant than children with TD (F-test, p < 0.01) while the mean values were similar. Conclusions: The findings indicate that, in comparison to children with TD, children with ASD demonstrated significantly less tau-coupling with higher variability during swipes whilst engaging in smart-tablet gameplay. It should be noted that the coupling constant in ASD was significantly more variable, however, the mean value was similar to what was observed in TD. The results of the coupling constant imply that, for the overall movement, children with ASD and TD used similar strategies to perform the goal-oriented swipes while greater fluctuations were observed in ASD. These findings are consistent with previous reports indicating that individuals with ASD have difficulties in controlling goal-oriented movement efficiently with increased subsecond motor variability during the travel of the movement (Torres et al., 2013). Increased acceleration and jerk amplitudes noted in adults with ASD (Cook et al., 2013) suggests sensorimotor and timing are disrupted at the level of the brainstem integration (Delafield-Butt & Trevarthen, 2017). Therefore, disruption to efficient perception-action regulation by tau-coupling might be a critical motor disruption in ASD
