Susceptibility to a multisensory speech illusion in older persons is driven by perceptual processes.

Recent studies suggest that multisensory integration is enhanced in older adults but it is not known whether this enhancement is solely driven by perceptual processes or affected by cognitive processes. Using the "McGurk illusion," in Experiment 1 we found that audio-visual integration of incongruent audio-visual words was higher in older adults than in younger adults, although the recognition of either audio- or visual-only presented words was the same across groups. In Experiment 2 we tested recall of sentences within which an incongruent audio-visual speech word was embedded. The overall semantic meaning of the sentence was compatible with either one of the unisensory components of the target word and/or with the illusory percept. Older participants recalled more illusory audio-visual words in sentences than younger adults, however, there was no differential effect of word compatibility on recall for the two groups. Our findings suggest that the relatively high susceptibility to the audio-visual speech illusion in older participants is due more to perceptual than cognitive processing.

Factors associated with perceived health in older adult Irish population.

OBJECTIVES: Perceived health status or self-reported health declines with age and is associated with increased morbidity, mortality, poor mental health and functional outcomes and health care utilisation. The aim of this study was to investigate the relationship between a range of biopsychosocial measures and self-reported health in a sample of community-dwelling older people living in Dublin. METHOD: A total of 492 participants with a mean age of 72.5 (SD = 7.34) were assessed at the Technology Research for Independent Living (TRIL) clinic, a comprehensive geriatric assessment facility in St James's Hospital, Dublin, using standardised measures of medical morbidity, personality, functional status, depression, anxiety, perceived stress, cognition, loneliness and social support. The relationship between self-rated health and health measures was analysed using bivariate correlations and backward multiple regression. Indirect pathways of effects on perceived health were evaluated using bootstrapping mediation analysis. RESULTS: Self-rated health was best predicted by instrumental activities of daily living (IADL), Charlson Co-morbidity Index (CCI), extraversion and perceived stress. The effects of cognition and social support from friends on self-rated health were found to be mediated by elements of these identified factors. CONCLUSION: Self-rated health is not simply the absence of physical illness but is also strongly influenced by the degree of functional impairment, personality factors and the level of stress experienced by the older person.

The effect of combined sensory and semantic components on audio-visual speech perception in older adults.

Previous studies have found that perception in older people benefits from multisensory over unisensory information. As normal speech recognition is affected by both the auditory input and the visual lip movements of the speaker, we investigated the efficiency of audio and visual integration in an older population by manipulating the relative reliability of the auditory and visual information in speech. We also investigated the role of the semantic context of the sentence to assess whether audio-visual integration is affected by top-down semantic processing. We presented participants with audio-visual sentences in which the visual component was either blurred or not blurred. We found that there was a greater cost in recall performance for semantically meaningless speech in the audio-visual 'blur' compared to audio-visual 'no blur' condition and this effect was specific to the older group. Our findings have implications for understanding how aging affects efficient multisensory integration for the perception of speech and suggests that multisensory inputs may benefit speech perception in older adults when the semantic content of the speech is unpredictable.

Is inefficient multisensory processing associated with falls in older people?

Although falling is a significant problem for older persons, little is understood about its underlying causes. Spatial cognition and balance maintenance rely on the efficient integration of information across the main senses. We investigated general multisensory efficiency in older persons with a history of falls compared to age- and sensory acuity-matched controls and younger adults using a sound-induced flash illusion. Older fallers were as susceptible to the illusion as age-matched, non-fallers or younger adults at a short delay of 70 ms between the auditory and visual stimuli. Both older adult groups were more susceptible to the illusion at longer SOAs than younger adults. However, with increasing delays between the visual and auditory stimuli, older fallers did not show a decline in the frequency at which the illusion was experienced even with delays of up to 270 ms. We argue that this relatively higher susceptibility to the illusion reflects inefficient audio-visual processing in the central nervous system and has important implications for the diagnosis and rehabilitation of falling in older persons.