The temporal locus of the Knowledge of Results (KR) is composed by three intervals: pre KR, post-KR, and inter trial interval. A problem regarding this topic is that the manipulation of one interval implies in changing the others, suggesting that the intervals may be combined for analysis. The present study investigated the effects of temporal locus of the KR in the motor skills acquisition. A manual positioning task consisting of the transport of three tennis balls between six containers in a specific sequence and time was used. The apparatus was comprised of a platform with six containers and a central controller connected to a computer. An acquisition phase of 30 trials using the 4-2/5-3/6-1 sequence and a 3,000 msec target time was allowed. The immediate transfer tests and the delayed transfer tests were performed ten minutes and twenty four hours after the completion of the acquisition phase, respectively. Both tests were preceded by 15 practice trials in a previously unknown movement sequence (6-1/5-3/4-2) and target time (4,000 msec.) without any KR. Ninety undergraduate students were allocated into nine groups (n = 10). Three groups had a four-second interval between trials; three groups had an eight-second intertrial interval; the reaming three groups had a sixteen-second intertrial interval. All groups had distinct pre and post-KR intervals. The results showed that smaller intertrial intervals resulted in better testing performance. It suggests that the time for information processing should not be long, as it increases both the attention and memory demands.
Feedback; Knowledge of results; KR Delay; Intertrial interval
