Article

Postural control is a highly automatized basic activity that requires limited
attentional investments. These investments have been shown to increase from
balancing experts to controls, and from controls to persons with impaired
postural control. Such between-subject comparisons led to a proposed direct
relation between the regularity of center-of-pressure (COP) fluctuations and the
amount of attention invested in posture. This study aims to expand this relation
to a within-subject comparison of conditions that differ in balance demands.
Specifically, more regular COP fluctuations were expected for standing than
sitting, as stimulus-response reaction-time studies showed that the required
attentional demands are lower for sitting than standing. COP registrations were
made for fifteen healthy young adults in seated and standing postures. COP
regularity was quantified with sample entropy. As expected, COP fluctuations were
found to be more regular for standing than sitting, as evidenced by significantly
lower sample entropy values. These findings expand the relation between COP
regularity and the amount of attention invested in posture to postural tasks that
vary in balance demands. An assessment of COP regularity may thus not only be
instrumental in the examination of attentional investment in posture in
between-subject designs, but also for different postures in within-subjects
designs.
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Langue : ANGLAIS