The use of predictive information is impaired in the actions of children and young adults with Developmental Coordination Disorder

Abstract

The need for a movement response may often be preceded by some advance information regarding direction or extent. We examined the ability of individuals with Developmental Coordination Disorder (DCD) to organise a movement in response to advance information. Pre-cues were presented and varied in the extent to which they indicated the response target. Both eye movement latencies and hand movements were measured. In the absence of pre-cues, individuals with DCD were as fast in initial hand movements as the typically developing (TD) participants, but were less efficient at correcting initial directional errors. A major difference was seen in the degree to which each group could use advance pre-cue information. TD participants were able to use pre-cue information to refine their actions. For the individuals with DCD this was only effective if there was no ambiguity in the advance cue and they had particular difficulty in using predictive motion cues. There were no differences in the speed of gaze responses which excluded an explanation relating to the dynamic allocation of attention. Individuals with DCD continued to rely on the slower strategy of fixating the target prior to initiating a hand movement, rather than using advance information to set initial movement parameters.

Appendix I

Additional analyses were carried out on the components of the hand movement measure (hand onset, average velocity and heading error at 200 ms) for percentage improved values of these see Table 3.

For hand onset a main effect of cue and group was found for, static peripheral cueing [cue, F(1,42) = 16.97 P < 0.001 η² = 0.22, group F(1,42) = 4.64 P = 0.037 η² = 0.10], static central cueing [cue, F(1,42) = 13.34 P = 0.001 η² = 0.24, group, F(1,42) = 13.75 P = 0.001 η² = 0.25], predictive motion 4 target cueing [cue, F(2,84) = 20.69 P < 0.001 η² = 0.33, group, F(142) = 15.12 P < 0.001 η² = 0.26] and predictive motion 12 target cueing [cue, F(2,84) = 12.71 P < 0.001 η² = 0.23, group, F(1,42) = 18.18 P < 0.001 η² = 0.30].

For average velocity a main effect of cue was found for, static peripheral cueing [F(1,42) = 36.42 P < 0.001 η² = 0.46], static central cueing [F(1,42) = 6.28 P = 0.016 η² = 0.130], predictive motion 4 target cueing [F(2,84) = 2.53 P = 0.086 η² = 0.057] and predictive motion 12 target cueing [F(2,84) = 1.69 P = 0.191]. No effects of groups were found.

For heading error 200 ms after hand onset the results were as follows: static peripheral cueing [group, F(1,42) = 10.18 P = 0.003 η² = 0.19, no effect of cue]; static central cueing [cue, F(1,42) = 34.49 P < 0.001 η² = 0.45, group, F(1,42) = 11.70 P = 0.001 η² = 0.22]; predictive motion 4 target cueing [group, F(1,42) = 10.67 P = 0.002 η² = 0.20, no effect of cue]; and predictive motion 12 target cueing [cue, F(2,84) = 6.24 P = 0.003 η² = 0.13, group, F(1,42) = 7.41 P = 0.009 η² = 0.15].