Frontiers in Aging Neuroscience Aging Neuroscience

Abstract

a control group that did not exercise. Improvements in cardiorespi-ratory function were found in the training group only, along with improvements in a simple RT task. Similar results were obtained in women aged 57–85 years old, following a 3-year physical training program (Rikli and Edwards, 1991). Hawkins et al. (1992) reported that, in older adults, a 10-week aquatic fitness program, led to larger improvement in tasks conditions that tap dual-task and switching abilities compared to conditions that do not require executive or attentional control processes. Kramer et al. (1999) also observed that after a 6-month walking program, participants (aged 65–70 years old) showed significant improvement in task conditions that required executive or controlled functions. These findings have been further supported in a recent meta-analysis on 18 intervention studies with participants aged 60 years and older (see Colcombe and Kramer, 2003; but see Etnier et al., 2006 for different conclusions). Most of the studies reported previously suggest that in older adults, enhancing aerobic fitness leads to significant improvement in attentional control functions. However, some of them that used RT paradigms, reported equivalent improvement after training, in both simple and choice RT tasks. This observation is at odds with the assumption that fitness training has a larger impact on the controlled aspect of cognition, which should lead to larger training effects on choice compared to simple RT tasks (Hall et al., 2001). Surprisingly, few studies have directly compared improvement in simple and choice RT tasks after aerobic fitness training. Moreover, RT tasks often vary among studies in term of decision complexity and the ability to predict the moment at which a stimulus will occur. Indeed, RT tasks may engage controlled aspects of attention before the stimulus occurrence if anticipation or response preparation can take place (Niemi and Näätänen, 1981).