Older adults can rely on an auditory cue to generate anticipatory postural adjustments prior to an external perturbation

Abstract

To minimize the potential postural disturbance induced by predictable external perturbations, humans generate anticipatory postural adjustments (APAs) using visual information about a perturbation. However, it is unknown whether older adults can generate APAs relying on auditory information. Ten older adults received external perturbations (a) with visual information but no auditory information available, (b) without neither visual nor auditory information, (c) with both visual and auditory information available, and (d) participated in training with only auditory information available. In addition, they were tested again after 1 week of washout period. Electromyography activities of eight leg and trunk muscles and ground reaction forces were recorded and analyzed during the anticipatory and compensatory phases. Outcome measures included the latencies and integrals of muscle activities, and center-of-pressure displacements. After a short period of training, participants were able to rely on the auditory cue only to generate APAs close to that when the visual information was available. In addition, after 1 week of washout period, they were able to partially retain the skill to rely on auditory cues to generate APAs. The outcome provides a foundation for future studies focusing on utilizing auditory cues to optimize postural control in individuals who have balance or vision deficit.

Greater Effect of Auditory Stimuli Than Visual Stimuli on Anticipatory Postural Adjustments Increase

“…However, when the task is unexpected, APA is not optimized. The same reports have been confirmed for auditory cues, which, as a conditioning stimulus, can trigger APA in healthy individuals against an external perturbation in youth adult (26).…”

“…Visual information is usually serious to create effective APAs prior to postural disruption. Preceding studies similarly reported that healthy young adults could be dependent on an auditory cue to produce postural responses to outer perturbation (26). All the researchers stated that when larger APAs were produced for an external postural perturbation, less postural instability was detected.…”

“…In general, it seems that the mechanism of the auditory cue is different from the visual cue because the auditory cues provides people timing information. Therefore, the participants were able to rely on a new form of sensory information to calculate the postural perturbation and generate appropriate APA (26).…”