Research Paper Volume 10, Issue 12 pp 3866—3880
Serial position effects differ between Alzheimer’s and vascular features in mild cognitive impairment
- 1 Department of Neurology, National Neuroscience Institute, Singapore 308433, Singapore
- 2 Department of Neurology, Singapore General Hospital, Singapore 169856, Singapore
- 3 Duke-NUS Medical School, Singapore 169857, Singapore
Received: August 11, 2018 Accepted: November 18, 2018 Published: December 12, 2018
https://doi.org/10.18632/aging.101678How to Cite
Copyright: Chander et al. This is an open‐access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Individuals with mild cognitive impairment (MCI) exhibit varying serial position effect (SPE) performances. The relationship between SPE performance in word list recall and clinical, genetic, and neuroimaging features of MCI requires elucidation. 119 MCI and 68 cognitively normal (CN) participants underwent cognitive assessment, apolipoprotein E (ApoE) genotyping, and volumetric MRI brain scans processed via voxel-based morphometry. A 10-word recall task was used to assess SPE performance in relation to recency and primacy recall. MCI participants were classified as having Good SPE performance (high primacy and recency, Good SPE) or Poor SPE performance (low primacy only, LP-SPE; low recency only, LR-SPE; or both low, Low SPE). Poor SPE participants had reduced grey matter (GM) volumes and increased white matter hyperintensities (WMH) volumes. Participants with LP-SPE demonstrated reduced hippocampal GM volumes and were more likely to be ApoE ε4 carriers. LR-SPE was associated with higher WMH volumes. Presence of both greater WMH volumes and ApoE ε4 resulted in Low SPE. LP-SPE MCI participants had features typical of Alzheimer’s disease. LR-SPE MCI was associated with increased WMH volumes, likely representing vascular pathology. SPE profiles are associated with distinct clinical patterns of MCI pathophysiology and could have potential as a clinical marker.
Abbreviations
AD: Alzheimer’s disease; ADAS-Cog: Alzheimer’s Disease Assessment Scale – Cognitive; ADNI: Alzheimer’s Disease Neuroimaging Initiative; aMCI: amnestic mild cognitive impairment; BNT: Boston Naming Test; CAT12: Computational Anatomy Toolbox package; CDR: Clinical Dementia Rating scale; CN: cognitively normal; CTT: Color Trails Test; DWR: delayed word recall; FLAIR: fluid attenuated inversion recovery MR sequence; GDS: Geriatric Depression Scale; GM: grey matter; ICBM: International Consortium for Brain Mapping; IWR: immediate word recall; LP-SPE: low primacy only serial position effect; LR-SPE: low recency only serial position effect; MCI: mild cognitive impairment; MMSE: Mini-Mental State Examination; MoCA-SG: Montreal Cognitive Assessment – Singapore version; MPRAGE: magnetization-prepared rapid gradient-echo MR sequence; naMCI: non-amnestic mild cognitive impairment; pvWMH: periventricular white matter hyperintensities; SPE: serial position effect; SPM: Statistical Parametric Mapping 12 software; TIV: total intracranial volume; VBM: voxel-based morphometry; VCI: vascular cognitive impairment; WAIS-IV: Wechsler Adult Intelligence Scale – Fourth edition; WM: white matter; WMS-IV: Wechsler Memory Scale – Fourth edition; WMH: white matter hyperintensities.