1. Neurocognitive markers of cognitive impairment: Exploring the roles of speed and inconsistency
- Author
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Roger A. Dixon, Douglas D. Garrett, Tanya L. Lentz, Stuart W. S. MacDonald, Esther Strauss, and David F. Hultsch
- Subjects
Male ,Health Status ,Decision Making ,Individuality ,Neuropsychological Tests ,Choice Behavior ,Vocabulary ,050105 experimental psychology ,Education ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Memory ,Predictive Value of Tests ,Reaction Time ,Humans ,0501 psychology and cognitive sciences ,Longitudinal Studies ,Aged ,Aged, 80 and over ,Sex Characteristics ,Verbal Behavior ,Working memory ,05 social sciences ,Middle Aged ,Semantics ,Cross-Sectional Studies ,Neuropsychology and Physiological Psychology ,Data Interpretation, Statistical ,Female ,Cognition Disorders ,Psychology ,Psychomotor Performance ,030217 neurology & neurosurgery ,Cognitive psychology - Abstract
A well-known challenge for research in the cognitive neuropsychology of aging is to distinguish between the deficits and changes associated with normal aging and those indicative of early cognitive impairment. In a series of 2 studies, the authors explored whether 2 neurocognitive markers, speed (mean level) and inconsistency (intraindividual variability), distinguished between age groups (64-73 and 74-90+ years) and cognitive status groups (nonimpaired, mildly impaired, and moderately impaired). Study 1 (n = 416) showed that both level and inconsistency distinguished between the age and 2 cognitive status (not impaired, mildly impaired) groups, with a modest tendency for inconsistency to predict group membership over and above mean level. Study 2 (n = 304) replicated these results but extended them because of the qualifying effects associated with the unique moderately impaired oldest group. Specifically, not only were the groups more firmly distinguished by both indicators of speed, but evidence for the differential contribution of performance inconsistency was stronger. Neurocognitive markers of speed and inconsistency may be leading indicators of emerging cognitive impairment.
- Published
- 2007
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