UPRIGHT STANDING AND GAIT - ARE THERE CHANGES IN ATTENTIONAL REQUIREMENTS RELATED TO NORMAL AGING

This study evaluates attentional requirements for maintaining an uprig ht posture and for walking among young and elderly persons to determin e if, with normal aging, there is a deficit and/or a modification in t he allocation of the attentional resources necessary for balance contr ol. Eight young adults and 8 elderly persons were asked to respond to an auditory reaction time (RT) task (secondary task) while in a seated position, while in a broad-support or narrow-support upright standing position, and while walking (primary tasks). Reducing the base of sup port yielded slower RTs for the elderly than for the young persons. Wh en walking, the elderly persons adopted a slower speed than young pers ons. They also had a shorter stride length. These adaptations have bee n reported to produce a more secure gait. Even so, they responded to t he probe RT task with greater delays than young adults. Together, the results suggest that normal aging requires that a greater proportion o f attentional resources be allocated to the balance demands of postura l tasks.