ABSTRACT
The role of attention in postural control is important in a balanced task. The objective of this study is to compare the complexity of postural stability between healthy young and elderly faller subjects, with and without the influence of an additional attention task (dual-task). The "complexity" was used to reflect adaptability to change and to determine postural balance stability from the center of pressure (COP) signals. The COP data were collected from 13 elderly fallers and 15 healthy young subjects under standing still with or without additional attention task. The COP signals were pre-processed by empirical mode decomposition (EMD), and high frequency si~:,'llals were calculated as "complexity" through multi-scale entropy (MSE) analysis. With the view of complexity, our results showed that attention certainly has an influence on postural control for elderly fallers. In that group, the complexities in dual-task COP signals were lower than those when standing still, and they exhibited less postural stability under an attention influence. Those results indicated a poor adaptability to attention influences for elderly fallers.
