Effect of an attention demanding visual task on postural control in young and old adults

Abstract

Research indicates the attentional demands for balance increase with age. Age-related declines in balance may further increase the attentional demands associated with maintaining stability. PURPOSE: A dual-task paradigm was used to study the effects of an attentionally demanding visual task on postural control. METHODS: The static balance of ten young (22.7+ 3.9) and ten older (75.7+ 7.1) adults was evaluated under 3 conditions (Control [C], Word STROOP [WS], and Color STROOP [CS]). The STROOP task presents words printed in mismatching colors (e.g. "red" presented in blue ink). Participants are instructed to read aloud the word (WS) or the color the word is printed in (CS). The CS task is a more difficult and attentionally demanding task. Balance measures including Sway Index (SI), Sway Amplitude in the anterior-posterior (Amp-AP), Medial-lateral planes (Amp-ML), and Sway Speed in these planes (Spd-AP, Spd-ML) were obtained. RESULTS: The young and old adults differed significantly (p.>.05) on all balance measures for the C and WS conditions; under the CS condition the groups differed (p.>.05) in SI, Amp-ML and Spd-ML. There were no significant balance differences between the C and WS conditions suggesting speaking does not impact balance. The older adults displayed significant (p< .05) differences for SI, Amp-ML and Spd-ML between C and CS and WS and CS; and significant differences (p< .05) for Amp-AP and Spd-AP between C and CS. The young adults displayed significant (p< .05) differences for SI, Amp-AP and Spd-AP between C and CS and WS and CS. CONCLUSION: The results indicate that an attentionally demanding visual task negatively impacts balance for both young and old. Interestingly, the secondary task increased older adult sway in the M-L plane, whereas young adults sway more in the A-P plane. These results also suggest that visual attention processes may play an important role in the maintenance of static balance in older adults.