Mutual interference between a visual and a motor task in young and elderly subjects

Patrícia Pereira dos Santos Teixeira Mariana Callil Voos Mariane Silva Andrade Machado Lílian Zanchetta Castelli Luiz Eduardo Ribeiro do Valle Maria Elisa Pimentel Piemonte About the authors

Since aging brings about difficulty in dividing attention, this study aimed at verifying, in youth and aged: (1) the possible interference between a visual and a motor task; (2) whether such interference varies between young and elderly subjects; (3) whether there is correlation between the proposed tasks and the trail making test (TMT) and the timed up-and-go test (TUGT). The visual task measured the ability to state whether two quickly presented figures were same or different. The motor task consisted on alternating steps from the ground to a 10 cm-high platform. Tasks were assessed both as single-task (isolated) and dual-task (simultaneous) in two groups: 10 young people (aged 23±2.8) and 10 elderly (aged 68.8±8.6). In the visual task, young volunteers presented less errors than the elderly (p<0.001); in both groups no increase in the number of errors was detected at dual-task when compared to the single-task. At the motor task the elderly presented lower speed in dual-task as compared to the single-task (p=0.009). TMT correlated positively to the number of alternations of step (p<0.05) and TUGT correlated negatively to the number of alternations of step (p<0.05). For both young and elderly, the motor task did not interfere on the visual task; however, the elderly showed lesser speed in the motor task when associated to the visual task. The non-assignment of primality to either task proved useful to detect these interferences.

Aging; Motor activity; Task performance and analysis; Visual perception

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