Repetition blindness and homophone blindness in young and older adults.

We tested age effects on repetition blindness (RB), defined as the reduced probability of reporting a target word following presentation of the same word in a rapidly presented list. We also tested age effects on homophone blindness (HB), in which the first word is a homophone of the target word rather than a repeated word. Thirty young and 28 older adults viewed rapidly presented lists of words containing repeated, homophone, or unrepeated word pairs and reported all of the words immediately after each list. Older adults exhibited a greater degree of RB and HB than young adults using a conditional scoring method that provides certainty that blindness has occurred. The existence of RB and HB for both age groups, and increased blindness for older compared to young adults, supports predictions of a binding theory that has successfully accounted for a wide range of phenomena in cognitive aging.

The effects of age on using prosody to convey meaning and on judging communicative effectiveness.

We tested the effects of aging on the use of prosody to convey meaning and the ability to monitor communicative effectiveness. Participants read aloud ambiguous sentences with the goal of clearly communicating one designated meaning. Young and older adults produced intonational boundaries consistent with the designated meaning equally often, but listener judgments indicated that older adults disambiguated the sentences more often than chance and young adults did so only marginally more often than chance. Young adults believed they communicated their message clearly, and older adults evaluated their own communication even more favorably. Participants were more confident for structurally ambiguous sentences than for lexically ambiguous sentences (which cannot be differentiated through prosody), and older adults demonstrated more overconfidence than young adults for both types of ambiguous sentences.