Age-related effects of a memorizing spatial task in the adults and elderly postural control.

The aim of this study was to evaluate the age-related changes in postural control during a simple quiet standing task and a dual-task paradigm (applying a memory-spatial task and quiet standing). Thirty-five subjects were divided in two age-related groups: both younger (Y: 20-26 years) and older (O: 60-77 years) groups performed a simple postural task (quiet standing) and a dual-task (a visual memory task combined with quiet standing). Measures of the center of pressure (CoP) were recorded and its two components, the center of gravity (CG) and the differential CoP-CG, were evaluated. An age-related effect was observed in static postural performance during dual-tasking. Postural stability led to improved performance in younger subjects during the dual-task and but not in the elderly. Of the results suggest there is a "cognition first" principle for the younger adults, that is, the mirror image of the "posture first" principle observed in older adults under dual-tasking situations.