PMC

Experiment 1: Non-Variable RPM. Mean time-on-target. Note: Bar graph showing mean performance (time-on-target) for blocks of trials during Experiment 1 in children with ADHD (left bars in grouping), HFA (middle bars) and TD control children (right bars in grouping). Subjects performed four blocks, each with four 20-sec trials. During the first, second and fourth blocks of trials the subjects tracked a light in a circular pattern; they tracked a square pattern in the third block. For Experiment 1, the pursuit rotor was set at the same speed (20 RPM) for each subject. Repeated measures ANOVA revealed a significant main effect of diagnosis across the blocks of trials, with TD children showing greater time-on-target than did children with HFA (P<0.0001) and children with ADHD (P<0.01). Motor learning was measured as change in time-on-target across the blocks of trials. Across all three groups there was a significant change in performance across the blocks of trials (P<0.0001). There was also a significant [(group) × (block)] interaction (P<0.0001), indicating that the amount of learning across all blocks differed among the groups. Follow-up two-group analyses revealed a significant [(group) × (block)] interaction for both TD vs. HFA (P<0.0001) and ADHD vs. HFA (P =0.019), with children with HFA showing less change in time-on-target across the blocks of trials than both TD children and children with ADHD. There was no significant [(group) × (block)] interaction for TD vs. ADHD. Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com. RPM, revolution per minute; ADHD, attention-deficit/hyperactivity disorder; HFA, high-functioning autism; TD, typically developing; ANOVA, analysis of variance. [Color figure can be viewed in the online issue which is available at www.interscience.wiley.com]

Experiment 2: Variable RPM. Mean time-on-target. Note: Bar graph showing mean performance (time-on-target) for blocks of trials during Experiment 1 in children with ADHD (left bars in groupings), HFA (middle bars) and TD control children (right bars in grouping). Subjects performed four blocks, each with four 20-sec trials. During the first, second and fourth blocks of trials the subjects tracked a light in a circular pattern; they tracked a square pattern in the third block. For Experiment 2, the speed of the pursuit rotor was calibrated on an individual basis to minimize differences in motor execution. Repeated measures ANOVA revealed no significant effect of diagnosis across the blocks of trials (P>0.05). Motor learning was measured as a change in time-on-target across the blocks of trials. Across all three groups there was a significant change in performance across the blocks of trials (P<0.0001). There was also a significant [(group) × (block)] interaction (P =0.011), indicating that the amount of learning across all blocks differed among the groups. Consistent with Experiment 1, follow-up two-group analyses revealed a significant [(group) × (block)] interaction for the TD vs. HFA (P =0.001), with children with HFA showing less change in time-on-target across the blocks of trials than the TD children. However, there was no significant [(group) × (block)] interaction for TD vs. ADHD or the ADHD vs. HFA. Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com. RPM, revolution per minute; ADHD, attention-deficit/hyperactiv-ity disorder; HFA, high-functioning autism; TD, typically developing; ANOVA, analysis of variance. [Color figure can be viewed in the online issue which is available at www.interscience.wiley.com]