The effect of slowing speech rate at natural boundaries on older adults' memory for auditorially presented stories

This investigation examined whether elderly people benefit from theoretically based adjustments to heard information. Speech rate was slowed by inserting pauses at syntactic boundaries (e.g., clause boundaries, sentence endings), and both recall and recognition memory for the information was assessed. Sixty-nine people (55-83 years) each listened to three stories (speech rates 175, 115, and 75 wpm), and read a fourth. Participants recalled more and recognised more accurately from the slowed speech. More higher order information (main points) than lower order information (details) was recalled, but this did not interact with speech rate. However, there was a speech-rate by recognition-error type interaction, suggesting that memory for higher order information (meaning) was enhanced by giving more time for processing at natural boundaries, and lower level information (surface structure) was forgotten when working memory was taxed. Although previous research has found a memory advantage for read text over heard text, we found an advantage for heard information at the slower rates. In conclusion, slowing speech rate at syntactic boundaries considerably benefited memory for heard information