Reexamining Synthetic Speech: Intelligibility and the Effects of Age, Task, and Speech Type on Recall

Abstract

Synthetic speech is a technology that can be utilized to convey information and aid people in their tasks. Older adults in particular are a population that may be able to benefit from synthetic speech, and they are a population that has been investigated in a limited capacity. The current researchers intended to elucidate lingering conflicts in previous research on the intelligibility and recall of word and stories in synthetic speech for older and younger adults and how that compared to similar conditions in natural speech. Twenty-four older and 24 younger adults completed intelligibility and recall tasks with word lists and stories. Results indicated that older adults had a more difficult time with all speech, natural speech was easier to understand and remember than synthetic speech, and stories were easier to recall than words. Results also indicated that older adults had a more difficult time understanding synthetic words as compared to natural words than younger adults. In addition, older adults improved differentially with the recall of stories as opposed to words when compared to the younger adult group. Potential directions for synthetic speech software design and future research are discussed.