Abstract
OBJECTIVES: To examine whether therapeutic interventions of extended practice of cognitive tasks or aerobic exercise have led to significant improvement in untrained cognitive tasks. DESIGN: The PSYCINFO, MEDLINE, and Abstracts in Social Gerontology databases were searched for English-language studies of cognitive interventions of exercise or extended cognitive practice between 1966 and 2010. The final search was in January 2011. Studies included were experimental interventions hypothesizing improvement on untrained cognitive outcomes with pre- and posttests. Studies of varying quality were included and compared. SETTING: Interventions generally took place in laboratories, in gymnasium facilities, in the home, and outdoors. Experimenters administered testing. PARTICIPANTS: Forty-two studies with 3,781 healthy older adults aged 55 and older were analyzed. MEASUREMENTS: Between-group effect sizes (ESs), which account for practice effects on outcome measures, and within-experimental group ESs were computed from untrained cognitive outcome domains, including choice reaction time, memory, and executive function, and compared. ESs were also coded for training type and study quality. Multilevel mixed-effect analyses accommodated multiple outcomes from individual studies. RESULTS: Extended practice (estimated ES = 0.33, 95% confidence interval (CI) = 0.13-0.52) and aerobic fitness (estimated ES = 0.33, 95% CI = 0.10-0.55) training produced significant between-group ESs, but they did not differ in magnitude. Better study quality was associated with larger ESs. CONCLUSION: Findings indicate that aerobic and extended cognitive practice training interventions for healthy older adults improve performance on untrained cognitive tasks.