Brain white matter tract integrity and cognitive abilities in community-dwelling older people: the Lothian Birth Cohort, 1936.
Neuropsychology
; 27(5): 595-607, 2013 Sep.
Article
em En
| MEDLINE
| ID: mdl-23937481
ABSTRACT
OBJECTIVE:
The present study investigates associations between brain white matter tract integrity and cognitive abilities in community-dwelling older people (N = 655). We explored two potential confounds of white matter tract-cognition associations in later life (a) whether the associations between tracts and specific cognitive abilities are accounted for by general cognitive ability (g); and (b) how the presence of atrophy and white matter lesions affect these associations.METHOD:
Tract integrity was determined using quantitative diffusion magnetic resonance imaging tractography (tract-averaged fractional anisotropy [FA]). Using confirmatory factor analysis, we compared first-order and bifactor models to investigate whether specific tract-ability associations were accounted for by g.RESULTS:
Significant associations were found between g and FA in bilateral anterior thalamic radiations (r range .16-.18, p < .01), uncinate (r range .19-.26, p < .001), arcuate fasciculi (r range .11-.12, p < .05), and the splenium of corpus callosum (r = .14, p < .01). After controlling for g within the bifactor model, some significant specific cognitive domain associations remained. Results also suggest that the primary effects of controlling for whole brain integrity were on g associations, not specific abilities.CONCLUSION:
Results suggest that g accounts for most of, but not all, the tract-cognition associations in the current data. When controlling for age-related overall brain structural changes, only minor attenuations of the tract-cognition associations were found, and these were primarily with g. In totality, the results highlight the importance of controlling for g when investigating associations between specific cognitive abilities and neuropsychology variables.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Encéfalo
/
Envelhecimento
/
Cognição
/
Memória
Tipo de estudo:
Etiology_studies
/
Incidence_studies
/
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Aged
/
Humans
País como assunto:
Europa
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article