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Aging, task complexity, and efficiency modes: the influence of working memory involvement on age differences in response times for verbal and visuospatial tasks.

Paul Verhaeghen·John Cerella·Chandramallika Basak
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Abstract

We examined the information-processing functions (response-time x load) of younger and older adults for two verbal and one visuo-spatial task; each task was implemented in a baseline and a high-complexity condition. Heightened complexity transformed the baseline functions in either an additive or a multiplicative fashion. The processing efficiency of older adults was defined as the old-young ratio of the slopes of the load functions. Three levels of efficiency could be distinguished. The first level, with an age-related slowing factor of about 1.2, consisted of low-complexity verbal processing and additive-complexity verbal processing. The second level, associated with a slowing factor of about 1.6, consisted of a mixture of verbal-high-multiplicative-complexity processing and visuo-spatial-low-complexity processing. The third level, with a slowing factor of about 4, consisted of visuo-spatial processing of high multiplicative complexity. The results go against any common factor theory of aging. Instead, they suggest that a shift from a higher to a lower mode of efficiency is triggered by a greater degree of working memory involvement.

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AdolescentAdultAgedAgingAttentionDiscrimination LearningEfficiencyFemaleHumansImaginationMaleMathematicsMemory, Short-TermMiddle AgedOrientationPattern Recognition, VisualProblem SolvingPsychomotor PerformanceReaction TimeReadingSpeech PerceptionJournal ArticleResearch Support, N.I.H., Extramural

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Paul Verhaeghen, John Cerella, Chandramallika Basak. 2006. Aging, task complexity, and efficiency modes: the influence of working memory involvement on age differences in response times for verbal and visuospatial tasks.. https://doi.org/10.1080/138255890969267

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