title: Effects of apolipoprotein E genotype on spatial attention, working memory, and their interaction in healthy, middle-aged adults: results From the National Institute of Mental Health's BIOCARD study.
abstract: The cognitive consequences of the apolipoprotein E-epsilon4 (APOE-epsilon4) allele were examined in middle age, before likely onset of symptoms of Alzheimer's disease. The authors identified 3 cognitive processes--visuospatial attention, spatial working memory, and the effect of visuospatial attention on working memory--and devised "behavioral assays" of the integrity of components of these processes. Redirecting visuospatial attention, retention of memory for location, and attentional modulation of memory of target location were affected by APOE genotype. Visuospatial attention showed additive effects of epsilon4 gene dose; each additional epsilon4 allele inherited further slowed disengagement from invalidly cued space. In contrast, working memory performance was affected only in epsilon4 homozygotes. Effect sizes for the APOE gene were moderate to large, ranging from 14% to 24%. Effects of APOE genotype on component processes of cognition in healthy, middle-aged adults is consistent with the emergence in adulthood of an APOE-epsilon4 cognitive phenotype.
authors.affiliation: Cognitive Science Laboratory, Catholic University of America, Washington, DC, USA. pgreenw1@gmu.edu
authors.forename: P M
authors.initials: PM
authors.lastname: Greenwood
authors.forename: Chantal
authors.initials: C
authors.lastname: Lambert
authors.forename: Trey
authors.initials: T
authors.lastname: Sunderland
authors.forename: Raja
authors.initials: R
authors.lastname: Parasuraman
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D000544:Alzheimer Disease; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D005227:Fatty Acids; D005260:Female; D005838:Genotype; D006801:Humans; D007211:Indoles; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009315:National Institute of Mental Health (U.S.); D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D018570:Risk Assessment; D013028:Space Perception / Q000502:physiology*; D014481:United States
chemical_list: D053327:Apolipoprotein E4; D001057:Apolipoproteins E; C107235:CU 23; D005227:Fatty Acids; D007211:Indoles