title: Reverse causation in activity-cognitive ability associations: the Lothian Birth Cohort 1936.
abstract: Active lifestyles might protect cognitive abilities; however, studies rarely consider the reverse causal direction. Activity-cognition associations might reflect stable intelligence differences rather than a protective effect of activity. The Lothian Birth Cohort 1936 (n = 1091) completed cognitive tests aged 70, having taken an intelligence test aged 11. Activity (assessed by participation in 15 activities that produced a socio-intellectual activity factor, and by physical activity) was positively associated with cognition (r = .08 to .32, p ≤ .05). When age-11 IQ and adult social class were controlled, only physical activity remained significantly associated with general cognitive ability and processing speed.
authors.affiliation: Centre for Cognitive Ageing and Cognitive Epidemiology, Department of Psychology, University of Edinburgh, Edinburgh, UK. alan.gow@ed.ac.uk
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Gow
authors.forename: Janie
authors.initials: J
authors.lastname: Corley
authors.forename: John M
authors.initials: JM
authors.lastname: Starr
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Deary
mesh_terms: D000368:Aged; D000375:Aging / Q000523:psychology*; D015984:Causality; D002648:Child; D003071:Cognition / Q000502:physiology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D015444:Exercise / Q000523:psychology*; D005260:Female; D006801:Humans; D007360:Intelligence / Q000502:physiology; D007899:Leisure Activities; D008019:Life Style; D016014:Linear Models; D008297:Male; D011594:Psychometrics; D014888:Wechsler Scales