Onset asynchrony in spoken menus

The menu is an important interface component, which appears unlikely to be completely superseded by modern search-based approaches. For someone who is unable to attend a screen visually, however, alternative non-visual menu formats are often problematic. A display is developed in which multiple concurrent words are presented with different amounts of onset asynchrony. The effect of different amounts of asynchrony and word length on task durations, accuracy and workload are explored. It is found that total task duration is significantly affected by both onset asynchrony and word duration. Error rates are significantly affected by both onset asynchrony, word length and their interaction, whilst subjective workload scores are only significantly affected by onset asynchrony. Overall, the results appear to suggest that the best compromise between accuracy, workload and speed may be achieved through presenting shorter or temporally-compressed words with a short inter-stimuli interval.