Related Experiment Videos
Serial position effects differ between Alzheimer's and vascular features in mild cognitive impairment
Russell Jude Chander1, Heidi Foo1, Tingting Yong1
1Department of Neurology, National Neuroscience Institute, Singapore 308433, Singapore.
Aging
|December 13, 2018
Summary
Serial position effect (SPE) in mild cognitive impairment (MCI) reveals distinct patterns. Poor SPE performance correlates with reduced brain volume and genetic factors, suggesting potential as a clinical marker for MCI subtypes.
Area of Science:
- Neuroscience
- Cognitive Psychology
- Medical Imaging
Background:
- Mild cognitive impairment (MCI) presents heterogeneous cognitive profiles.
- The serial position effect (SPE), reflecting memory for early (primacy) and late (recency) items, varies among individuals with MCI.
- Understanding the link between SPE performance and underlying MCI pathophysiology is crucial.
Purpose of the Study:
- To investigate the relationship between SPE performance in word list recall and clinical, genetic (apolipoprotein E - ApoE), and neuroimaging (grey matter - GM, white matter hyperintensities - WMH) features in MCI.
- To differentiate MCI subtypes based on SPE performance (Good SPE, LP-SPE, LR-SPE, Low SPE).
Main Methods:
- 119 MCI and 68 cognitively normal (CN) participants underwent cognitive assessment, ApoE genotyping, and volumetric MRI with voxel-based morphometry.
- A 10-word list recall task assessed SPE, categorizing participants into Good SPE or Poor SPE (LP-SPE, LR-SPE, Low SPE) groups.
- Statistical analyses correlated SPE performance with GM/WMH volumes and ApoE ε4 carrier status.
Main Results:
- Poor SPE performance in MCI was associated with reduced GM volumes and increased WMH volumes.
- Low primacy recall (LP-SPE) was linked to reduced hippocampal GM and higher likelihood of ApoE ε4 carriage, suggesting Alzheimer's disease-like pathology.
- Low recency recall (LR-SPE) correlated with increased WMH volumes, indicative of vascular pathology.
- Combined WMH and ApoE ε4 presence predicted Low SPE.
Conclusions:
- SPE performance profiles in MCI are associated with distinct underlying pathophysiological mechanisms (neurodegenerative vs. vascular).
- LP-SPE MCI exhibits features suggestive of Alzheimer's disease, while LR-SPE MCI points towards vascular contributions.
- SPE may serve as a valuable, accessible clinical marker for stratifying MCI subtypes and understanding their pathology.