The Elderly's Response for Choice Reaction and Movement Time

Abstract

User interface plays important role in product safety and usability as an interactive part between user and product. In particular, in case of the elderly, bad user interface design causes some problems in aspect of usability and safety. In this aspect, this study was conducted to investigate the elderly’s characteristics of the elderly's choice reaction and movement time for elderly-centered universal design. In the elderly’s choice reaction time, the number of alternatives was three or more, the female's response times were greater than the male. And as the number of alternatives increased, the choice reaction time of the elderly was found to increase for both men and women, and was found to be appropriately expressed by a formula applying Hick's law. The choice reaction time tended to decrease as the experiment was repeated, but in repetitions of two or more times, the decrease appeared insignificant even if the number of repetitions increased. However, it was found that there was a significant decrease in reaction time for both men and women between the first and second experiments. In the elderly’s movement time, the movement time was affected by the index of difficulty (ID) that was calculated by moving distance and button size. In particular, the movement time was more steeply increased with the increment of ID in case of the elderly than the young. This study provides meaningful results in terms of identifying the general characteristics of elderly people regarding choice reaction and movement time, and these results can be used as basic data for future universal design.