Contextual Interference and Motor Skill Learning in Alzheimer’s Disease

This study examined the acquisition, retention, and transfer of a gross motor skill, namely, tossing, in 84 moderate-to-severely demented patients with Alzheimer’s disease (AD) and 72 healthy elderly controls. To identify optimal learning strategies, participants received 10 weeks of training under 1 of 5 practice conditions: constant, variable-parameter, variable-program, variable-combined, or no training. Constant practice was the only training condition that significantly enhanced learning and near transfer in AD patients. In comparison, all 4 types of training facilitated acquisition and near transfer in the healthy controls, with variable-combined practice being the most beneficial. The superiority of the variable practice conditions in the healthy controls supports both Schmidt’s (1975) variability of practice hypothesis and contextual interference theory. The inability of AD patients to benefit from variable forms of practice suggests that these impaired individuals may have difficulty accessing and/or forming motor schemas.