Absence of practice effects in preclinical Alzheimer's disease.

ABSTRACT:

Objective

To describe how practice effects influence cognitive trajectories and determine if a reduction in practice effects is a potential marker of Stage-III preclinical Alzheimer's disease (AD).

Method

Participants included 263 older adults who were cognitively normal at baseline (i.e., had a Clinical Dementia Rating [CDR] of 0; Morris, 1993) and returned for an average of 9.5 annual visits. Participants completed standard tests of episodic memory, visuospatial ability, semantic memory, and executive function. Progressors (n = 66) converted to CDR > 0 with a diagnosis of symptomatic AD after a minimum of 3 visits and stable participants (n = 197) never progressed to CDR > 0. Practice effects, defined as the slope of performance across Visits 1-3, were compared between gro

SUBMITTER: Hassenstab J 

PROVIDER: S-EPMC4640964 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature