Adult Lifespan Cognitive Variability in the Cross-Sectional Cam-CAN Cohort

International Journal of Environmental Research and Public Health

Emma Green³  Meredith A. Shafto¹  Fiona E. Matthews²  rib-type="author">Cam-CAN5contrib-type="author">Cam-CAN5<⁴  Simon R. White² 

[1] Centre for Speech, Language and the Brain, Department of Psychology, University of Cambridge, Downing Street, Cambridge CB2-3EB, UK;MRC Biostatistics Unit, Cambridge CB2-0SR, UK;Department of Public Health and Primary Care, Cambridge Institute of Public Health, Univeristy of Cambridge, Cambridge CB2-0SR, UK;Cambridge Centre for Ageing and Neuroscience (Cam-CAN), University of Cambridge and MRC Cognition and Brain Sciences Unit, Cambridge, UK, www.cam-can.com;

关键词: cognitive variability;    adult lifespan;    heterogeneity;    MMSE;    ceiling effects;    variance confounders;    verbal fluency;    episodic memory;   

DOI  :  10.3390/ijerph121215003

来源: mdpi

【 摘 要 】

This study examines variability across the age span in cognitive performance in a cross-sectional, population-based, adult lifespan cohort from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) study (n = 2680). A key question we highlight is whether using measures that are designed to detect age-related cognitive pathology may not be sensitive to, or reflective of, individual variability among younger adults. We present three issues that contribute to the debate for and against age-related increases in variability. Firstly, the need to formally define measures of central tendency and measures of variability. Secondly, in addition to the commonly addressed location-confounding (adjusting for covariates) there may exist changes in measures of variability due to confounder sub-groups. Finally, that increases in spread may be a result of floor or ceiling effects; where the measure is not sensitive enough at all ages. From the Cam-CAN study, a large population-based dataset, we demonstrate the existence of variability-confounding for the immediate episodic memory task; and show that increasing variance with age in our general cognitive measures is driven by a ceiling effect in younger age groups.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.