The effects of an interfering task on the learning of a complex motor skill.

Abstract

This expt. deals with the effects of introducing an interfering task at various stages in the learning of a motor skill, the S. A. M. Complex Coordination Test. The interfering task consisted of appropriate movements of a gear shift arrangement in response to a red or green light. Six matched groups of 22 college men were used. Learning was divided into six 26-trial stages. One group had the interfering task from Stage 1 onward, another from Stage 2 onward, etc. At each stage there was an initial sharp increase in time when the interfering task was being introduced for the 1st time at this stage; and, even with practice, the time score never reached the level of the subjects who had not been given the interfering task. With the exception of the group receiving interference after the first stage, each group, while in its first interference stage, gave a time score which significantly exceeded the mean times of other groups which had practiced with interference over one or more stages prior to that stage. After the first interference stage was passed, all interference groups continued to improve at essentially the same rate regardless of the proportion of interference and non-interference training. Increases in time scores upon first introduction of interference were absolutely and proportionately greater with increased amounts of practice on the Coordination Test alone. The amount of positive transfer from non-interference training also increased. Therefore, despite increasing interference, the absolute level of performance became increasingly better with greater numbers of training trials on the Coordination Test alone.