Psychology and Aging 1993, Vol. 8, No. 4,481-489 Copyright 1993 by the American Psychological Association, Inc. 0882-7974/93/S3.00 Typography Manipulations Can Affect Priming of Word Stem Completion in Older and Younger Adults Janet M. Gibson, John O. Brooks III, Leah Friedman, and Jerome A. Yesavage The experiments reported here investigated whether changes of typography affected priming of word stem completion performance in older and younger adults. Across all experiments, the typeface in which a word appeared at presentation either did or did not match that of its 3-letter stem at test. In Experiment 1, no significant evidence of a typography effect was found when words were presented with a sentence judgment or letter judgment task. However, subsequent experiments revealed that, in both older and younger adults, only words presented with a syllable judgment task gave rise to the typography effect (Experiments 2-4). Specifically, performance was greater when the presentation and test typeface matched than when they did not. Experiment 5, which used stem-cued recall, did not reveal a difference between syllable and letter judgment tasks. These findings highlight the com- plex nature of word stem completion performance. Memory research with older adults has generally focused on deficits arising in tasks that require conscious recollection, such as recall or recognition (cf. Kausler, 1991). Older adults' deficits in recollective memory are all the more striking in view of find- ings that there are only slight, and sometimes undetectable, deficits in nonrecollective memory tasks (Hultsch, Masson, & Small, 1991). Compared with studies with younger adults, the factors that affect older adults' performance on nonrecollective tasks have only recently come under investigation (e.g., Chia- rello & Hoyer, 1988; Light, LaVoie, Valencia-Laver, Owens, & Mead, 1992; Light, Singh, & Capps, 1986; Russo & Parkin, 1993; cf. Graf, 1990). It is unclear whether manipulations that affect younger adults' performance would affect older adults' performance as well. One test of nonrecollective memory that has been used with older adults is the word stem completion test (e.g., Hultsch et al., 1991; Light et al., 1986). In this test, subjects are first pre- sented with a list of words and are later given a series of three- letter word beginnings, or stems, to complete with the first word that comes to mind (e.g., GAL for GALLANT). Priming is the increased probability of a word being used as a comple- tion, which reflects the effects of the prior exposure to the word Janet M. Gibson, Department of Psychology, Grinnell College; John O. Brooks III and Leah Friedman, Department of Psychiatry and Be- havioral Sciences, Stanford University School of Medicine; Jerome A. Yesavage, Psychiatry Service, Department of Veterans Affairs Medical Center, Palo Alto, California, and Department of Psychiatry and Be- havioral Sciences, Stanford University School of Medicine. This work was supported in part by National Institute of Mental Health Grant MH35182 to Jerome A. Yesavage and a Grinnell College grant to Janet M. Gibson. We would like to thank Henry L. Roediger for his comments on our findings and Christine Gray for her help in testing subjects. Correspondence concerning this article should be addressed to Janet M. Gibson, Department of Psychology, Grinnell College, Grinnell, Iowa 50112. Electronic mail may be sent to gibsonj@grin.edu or job@lcon.palo-alto.med.va.gov (Internet). in a presentation list. Are there age differences in priming of word stem completion? Not all researchers report such differ- ences, but there is growing evidence that such differences exist. Light and Singh (1987) administered a word stem completion test to both younger and older adults and found no evidence of age differences. Similarly, Java and Gardiner (1991) found that younger adults performed better than older adults on a cued recall test but that there was no significant difference in perfor- mance on a stem completion test. Chiarello and Hoyer (1988), however, reported that older adults exhibited less priming than did younger adults on a stem completion test. Davis et al. (1990) conducted a finer grained investigation and administered a word stem completion test to subjects who ranged in age from 18 to 90 years old. Davis et al. divided their subjects among seven age groups and found that subjects who were in their 70s or 80s showed impaired priming of stem completion relative to younger subjects. The inconsistent finding of age differences in priming of word stem completion performance may reflect a small magnitude of age differences or the fact that previous studies did not involve large numbers of subjects. Hultsch et al. (1991) adopted this reasoning and administered a word stem completion test to 96 subjects under the age of 37 years and 448 subjects between the ages of 55 and 89 years. The older subjects showed significantly less priming than did the younger subjects, but the difference was small (.02). Hultsch et al. thus concluded that the inconsis- tency of previous findings may have resulted from a lack of sta- tistical power. Though most studies have focused solely on age differences in the priming of word stem completion, a few have examined the effects of presentation task manipulations with older adults. Light and Singh (1987) had older subjects engage in either a vowel judgment task or a pleasantness rating task and then take a word stem completion test. Presumably, the vowel judgment task emphasized the structural aspects of the words, whereas the pleasantness rating task emphasized semantic aspects. Al- though the amount of priming was greater after the pleasantness 481 This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.