Older Adults’ Detection of Misspellings During Reading

ONE positive aspect of language processing in healthy older adults is the stability of the cognitive processes underlying perception and comprehension of individual words relative to their production (see Abrams & Farrell, in press; Burke & Shafto, 2008, for recent reviews). Despite considerable research on other perception tasks, research on older adults’ spelling detection has received little attention. In the studies that have been conducted, older adults’ detection of a word’s spelling as correct or misspelled is generally equivalent to college students (e.g., MacKay, Abrams, & Pedroza, 1999; Margolin & Abrams, 2007) or sometimes superior (Abrams & White, in press). However, conclusions about older adults’ performance have been made using relatively young groups of older adults. Furthermore, these studies assessed detection of single words’ spellings, not words embedded in any context. The purpose of the present experiment was to investigate whether misspelling detection processes remain stable within the older adult life span and in naturalistic settings such as reading, which more accurately represent conditions in which misspellings are encountered. There are reasons to suspect that the effects of age on misspelling detection may become more pronounced when looking at a broader range of ages. Theoretically, the transmission deficit hypothesis proposes that relative to bottom–up activation, top–down connectivity between the semantic representation of words and their constituent phonological and orthographic components become particularly vulnerable to age-linked decline (MacKay & Burke, 1990). Perception is less affected by age than production because the perception of a word begins with bottom–up processing of its features and results in a spread of activation to its corresponding lexical and semantic representations (e.g., Dell, 1986; Levelt, Roelofs, & Meyer, 1999; MacKay, 1987). However, although some perception tasks are completed at lexical access, spelling detection requires a top–down verification process (e.g., Paap, Newsome, McDonald, & Schvaneveldt, 1982), where the orthographic features of the word are confirmed. This latter spelling verification process may therefore be adversely influenced by aging and result in decreased misspelling detection with increasing age. Empirical support for this claim comes from Abrams and Stanley (2004), who conducted a signal detection analysis on younger adults’ and two groups of older adults’ judgments from a misspelling detection task. Of relevance here are the differences that emerged between the two older groups, where adults aged 73–85 years were less sensitive and more conservative than adults aged 61–72 years in detecting misspellings under some conditions. Adults in their 70s and 80s also show larger age-related declines relative to adults in their 60s on other cognitive tasks, such as implicit memory (e.g., Davis et al., 1990) and word naming (e.g., Au et al., 1995). Comparing older adults of different age ranges with each other can also be advantageous in that age-related changes to spelling processes can be examined without potential confounds from variables on which younger and older adults might differ, such as vocabulary, educational level, processing speed, working memory, and interest/relevance in the content. Furthermore, even when differences do occur between older adults of different age ranges on these variables, these differences are likely to be less pronounced than those between younger and older adults. The context in which misspelled words are presented may also be important for determining when age differences will occur. The majority of research on misspelling detection in old age has involved briefly showing words one at a time. When asked to judge the correctness of a word’s spelling, younger and older adults were equivalently accurate at detecting misspelled words (MacKay et al., 1999; Margolin & Abrams, 2007; see Abrams & Stanley, 2004, for an exception with rapid presentation rates). However, single-word presentation studies represent a limited context to assess misspelling detection and do not capture language processes in more real-world situations, such as reading, where detecting misspellings in sentences may become more difficult with advancing age because of the working memory resources required for successful comprehension (e.g., Just & Carpenter, 1992). The current experiment presented misspellings embedded in sentences about health-related topics to be read for recall. To assess possible influences of resource demands on misspelling detection during reading, we manipulated the position of the misspellings within the sentence, where misspellings could occur near the beginning, middle, or end of the sentence. We hypothesized that detecting misspellings near the end of the sentence may be particularly demanding of working memory because the reader has to hold the entire sentence until this point and synthesize its meaning for comprehension. Working memory capacity generally declines with advancing age even within older adulthood (e.g., De Beni, Borella, & Carretti, 2007), so old–old adults and middle-old adults may have exacerbated difficulty in detecting misspellings that occur later in the sentence relative to young–old adults.