Abstract:
Spoken word recognition may be characterized by two successive stages: (1) activation of multiple form-based representations in memory and (2) frequency-biased perceptual decision. Recent research has suggested that older adults show deficits in controlled processing in perceptual and memory tasks, suggesting that while activation mechanisms subserving spoken word recognition may remain relatively intact over time, perceptual decision processes degrade. In order to investigate the possible loci of older adults' recognition difficulties, perception of specially selected words that orthogonally varied on three dimensions was examined: word frequency, neighborhood density, and neighborhood frequency. Effects of neighborhood density are typically associated with activation mechanisms, whereas neighborhood frequency is associated with perceptual decision. The implications of these results for theories of aging and spoken word recognition will be discussed. [Work supported by grants from NIDCD.]