Abstract
Only a limited number of visually impaired people can independently operate talking automatic teller machines (ATMs). Beginners need understandable and effective voice guidance. The purpose of this paper is to experimentally determine the maximum number of items that users of talking ATMs can remember in transactions where they select a particular item after hearing all the items, when they are not familiar with the items. On the assumption that the uses of talking ATMs by young users who are blind or low vision, blindfold young participants were asked to memorize items with serial numbers presented by a synthetic voice and to give the serial number assigned to an item selected randomly from among the items in the experiments. The experimental variable was the number of items (Experiment I: 2, 3, 4, 5, Experiment II: 5, 7, 9, 11 conditions) presented in a single trial. The results showed that participants memorized the correct serial numbers faster and confidently under the 2- and 3-item conditions. In contrast, they gave incorrect answers when the number of items was 4 or more. These results suggest that the number of items remembered is related to short-term memory capacity. From the standpoint of memorability, voice guidance should be designed such that not more than 3 items are presented at a time.
