Overall, the findings suggest that the poorer performance of older adults in the AV condition was a result of reduced speechreading abilities rather than a consequence of impaired integration capacities. The pattern of correlations across the three stimulus types indicates some overlap in the mechanisms mediating AV perception of words and sentences and that these mechanisms are largely independent from those used for AV perception of consonants.

Overall, the results of the current study suggest that despite increased reliance on visual speech information, older adults who have hearing impairment do not exhibit better V speech perception or auditory-visual integration than age-matched individuals who have normal hearing. These findings indicate that inclusion of V and AV speech perception measures can provide important information for designing maximally effective audiological rehabilitation strategies.

In this study of visual (V-only) and audiovisual (AV) speech recognition in adults aged 22-92 years, the rate of age-related decrease in V-only performance was more than twice that in AV performance. Both auditory-only (A-only) and V-only performance were significant predictors of AV speech recognition, but age did not account for additional (unique) variance. Blurring the visual speech signal decreased speech recognition, and in AV conditions involving stimuli associated with equivalent unimodal performance for each participant, speech recognition remained constant from 22 to 92 years of age. Finally, principal components analysis revealed separate visual and auditory factors, but no evidence of an AV integration factor. Taken together, these results suggest that the benefit that comes from being able to see as well as hear a talker remains constant throughout adulthood, and that changes in this AV advantage are entirely driven by age-related changes in unimodal visual and auditory speech recognition.

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20-89 (n=388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domaindifferentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation. Keywords working memory; memory span; aging; individual differencesThe present study examines the structure of working memory abilities from the standpoint of both age and individual differences. Our approach builds on the distinction between simple and complex span tasks proposed by Engle and his colleagues (Engle, Tuholski, Laughlin, & Conway, 1999). According to Engle et al.'s original interpretation of this distinction, simple span tasks (e.g., digit span) primarily measure storage whereas complex span tasks (e.g., operation span, reading span) measure executive functions involved in coordinating storage and processing. More recently, however, Unsworth and Engle (2006, 2007a, 2007b), suggested that simple and complex span tasks also differ in the degree to which they rely on Correspondence concerning this article should be addressed to sshale@wustl.edu. 1 This interpretation could not be verified statistically because of the very large standard errors for these loadings, presumably because the verbal simple span tasks were allowed to load on two latent variables (primary and secondary memory) in Model 4c, creating a situation similar to multicollinearity in multiple regression. Publisher's Disclaimer:The following manuscript is the final accepted manuscript. It has not been subjected to the final copyediting, fact-checking, and proofreading required for formal publication. It is not the definitive, publisher-authenticated version. The American Psychological Association and its Council of Editors disclaim any responsibility or liabilities for errors or omissions of this manuscript version, any version derived from this manuscript by NIH, or other third parties. The published version is available at www.a...