The effects of overtraining on mediational processes in elderly males.

To examine the effects of overtraining on mediational processes, 81 male residents (aged 55 or above) of a VA domicillary were tested using a two-choice discrimination task. Upon reaching criterion, the men were given, 0, 15, or 30 overtraining trials and then shifted to either a reversal, intradimensional, or extradimensional task. Analysis of the error scores resulted in a significant initial versus shift task main effect and type of shift by initial versus shift task interaction. Further analysis indicated no difference among the three shift groups for the initial task. However, in the shift task, the reversal group had significantly fewer errors than the other two groups who were not statistically different. Participants thus appeared to be mediationally sufficient when reversal and extradimensional tasks were compared, but mediationally deficient when intra- and extradimensional, and reversal and intradimensional tasks were contrasted. While overtraining had no significant effect, examination of the three way interaction suggested potentially facilitative effects of overtraining and a possible regression effect among participants not receiving overtraining.