The Effects of Practice with Contextual Interference on the Motor Learning of Old Adults

Abstract

Introduction: Motor learning for the old adults plays an important role in the state of their health and quality of life. Previous studies on motor learning show the significant benefits of contextual interference effects on the long-term acquisition of motor skill (Hall & Magill, 1995). Thus, central to the research question in this study was: Will the benefits of contextual interference (CI) effects are the same for the old adults? Methods: Two experiments were administered in this study. Seventy-two old adults were served as participants and were divided into two groups for each experiment (Experiment 1: mean age = 67.6 years, SD = 4.2 years; Experiment 2: mean age = 66.9, SD = 4.7 years). The independent variable for the two experiments was the high/low degree of contextual interference inherent in the scheduling of either random or blocked practices. Experimental task were spatial movement pattern and relative timing in the two experiments respectively. The spatial movement patterns were 3 “Z” shapes computer keyboard typing format with 400ms, 300ms, and 200ms. The relative timing tasks were one “N” shape computer keyboard typing format with 200ms:100ms:300ms,400ms:200ms:600ms, and 600ms:300ms:900ms invariant feature of movement timing (Schmidt & Lee, 1999). The duration of each experiment lasts two consecutive days and there were 45 practice trials in each day for each participant. Ten trials were administered for both immediate and delayed retention tests. Dependent variables were variable error (VE) and absolute error (AE) with ms as unit. Independent one-way analysis of variance was performed respectively on the two dependent variables. Results: In experiment 1, it was found no CI effect on spatial movement pattern learning. Both AE and VE measures in immediate and delayed retention tests were found no significant differences among random, blocked, and control groups (p > .05). In experiment 2, it was also found no CI effect on relative timing learning. No significant difference was found in both AE and VE measure among 3 groups in delayed retention test. Control group even was found significant better than both random and blocked groups in AE measure during immediate retention test (p < .05). Discussion: The major finding of this study was that there was no CI effect on motor skill learning of old adults. One of the motor behavior characteristics of old adults is cautious as proposed by Welford (1977). Particularly when facing the interfered state during practices, they cognitively tend too careful in memorize the spatial and temporal requirements of the task to adopt the variability. This may be just opposite to the forgetting hypothesis of CI effect proposed by Lee and Magill (1985). Within the limitation of this finding, it is suggested that practice scheduling for old adults should be in repeated condition rather than interference-induced random condition. Further investigation need to be done to examine old adults' memory strategy during motor skill practice. Acknowledgements: This investigation was supported by Taiwan National Science Council grant NSC89-2413-H-003-015.