The effects of different knowledge of results spacing and summarizing techniques on the acquisition of a ballistic movement

The present study crossed three knowledge or results summarizing techniques single-trial KR, summary KR, and average KR) with two spacing conditions ( KR on every fifth trial 20% - and KR on every trial - 100%). Participant (n = 10 per group) performed 80 acquisition trials of a ballistic movement ta sk involving both a temporal and spatial goal, followed by 30 immediate (10 min) and 30 delayed (2 days) no-KR transfer trials. For the spatial goal, performance was less accurate (absolute constant error) for the 20% spacing condition than the 100% condition during acquisition, but more accurate du ring delayed transfer. No effect were significant for variable error. For t he temporal goal, performance was more accurate for the summary and average conditions than the single-trial KR condition; however, this effect was on ly present within the 20% spacing condition and only during Block 1 or acqu isition. A similar effect held for variable error as well, except that the effect persisted for acquisition and transfer. It was concluded that the sp acing of KR is more influential in promoting spatial accuracy than the summ arizing of KR.