Background: Alzheimer’s Disease (AD) is a neurodegenerative disorder that progresses from healthy aging to a preliminary stage known as preclinical AD. Preclinical AD is defined by intact global cognition and measures of pathological cerebral spinal fluid (CSF) amyloid ß1-42 and tau, deposition of amyloid ß plaques in the brain, or reduced hippocampal volume. Objectives: 1). Use a list learning task to compare probability of first recall (PFR) in older adults and college students (n=79). 2). Determine if PFR can distinguish between adults with and without preclinical AD. Method: Healthy older participants (n=20) were recruited from the Penn Memory Center and administered a free recall task with 24 lists at six lengths. Participants were randomly assigned to one of four groups in a 2x2 design with presentation speed (1 or 1.5 seconds) and articulation (reading words aloud or silently) as between subjects factors. Preclinical AD was determined using volumetric magnetic resonance imaging (MRI) of the hippocampus. PFR and a novel Primacy to Recency Shift Index (PRSI) determined participants’ tendency to use primacy or recency based first-recall strategies. Results: Reading aloud was associated with a more recency-based first recall pattern, especially on the two longest lists, supporting our hypotheses. PRSI scores and left hippocampal volumes showed a small, but nonsignificant, positive correlation indicating that primacy-based first recall strategies may be associated with greater hippocampal volume. Discussion: Articulating words by reading aloud during list learning is sufficiently taxing to alter first recall patterns on longer lists. Future research with a larger sample, comprehensive biomarker data, and a more demanding cognitive load manipulation is needed.
|School:||University of the Sciences in Philadelphia|
|Department:||Behavioral and Social Sciences|
|School Location:||United States -- Pennsylvania|
|Source:||MAI 58/04M(E), Masters Abstracts International|
|Subjects:||Behavioral psychology, Psychology|
|Keywords:||Preclinical ad, Primacy, Probability of first recall, Recency, Working memory|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be