Effects of Simultaneous Cognitive Task on Gait Event Accuracy with Auditory Stimuli: Comparison between Young Adults in Their 20s and the Elderly in their 70s

The purpose of this study was to compare the difference in the accuracy of gait events between young and older adults during metronomic walking by auditory cueing. Additionally, age-specific changes in the gait event accuracy according to additional simultaneous cognitive tasks were examined. The time interval (or temporal error) between the auditory cue (i.e., metronome) and the heel contact was used as the accuracy of the gait event. Fifteen young group (YG, 24.7 ± 0.8 years) and 14 elderly (EG, 78.4 ± 5.5 years) people participated in the experiment. The temporal errors under two gait conditions (MET: walking with metronome; MET + BC: walking with metronome while counting backward) were compared for each group. The results revealed that all the temporal errors of EG were significantly greater than those of YG. While the addition of simultaneous cognitive tasks resulted in a significant increase in temporal error in both age groups, the coefficient of variation (CV) of the temporal error significantly increased only in the EG group. In other words, although heel contact accuracy with auditory stimuli was affected by the simultaneous cognitive task in both groups, it was demonstrated that the variability of the error in the young adults remained constant. Therefore, the time error measurement used in this study has the potential to be used as a tool to judge the gait instability of the elderly compared with young adults.