Normal aging increases discriminal dispersion in visuospatial short term memory
2012 (English)In: Psychology and Aging, ISSN 0882-7974, E-ISSN 1939-1498, Vol. 27, no 3, 627-637 p.Article in journal (Refereed) Published
Computational models of cognitive aging propose that age-related decrements in cognitive performance, including short-term memory (STM), result from less distinct stimulus representations. When applied to visual STM, these models predict higher discriminal dispersion (L. L. Thurstone, 1927, Psychophysical analysis, The American Journal of Psychology, 38, 368-389.) in older adults than in younger adults. To test this prediction, we used a change-detection paradigm for visuospatial locations, with different levels of cognitive load (one, three, or five items) and retention interval (100 or 1,000 ms). Adult age differences were not reliable at Load 1, but were substantial at Loads 3 and 5. Effects of retention time did not differ across age groups, suggesting that age-related differences originated mainly from early processing stages. Applying a mixture model to the data revealed age-related increases in discriminal dispersion and decreases in asymptotic discrimination performance (indexing STM capacity). We concluded that age-related declines in discriminal dispersion, in addition to increasing capacity limitations, impair visual STM performance with advancing adult age.
Place, publisher, year, edition, pages
2012. Vol. 27, no 3, 627-637 p.
aging, visual short-term memory, change detection, discriminal dispersion
Psychology Gerontology, specializing in Medical and Health Sciences
IdentifiersURN: urn:nbn:se:su:diva-81825DOI: 10.1037/a0027251ISI: 000308679600009OAI: oai:DiVA.org:su-81825DiVA: diva2:565466