Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease
Abstract Background Reports from longer studies of preclinical Alzheimer’s disease (i.e., Aβ+ cognitively normal older adults) now show that performance on memory tests remains stable across re‐assessments, whereas in matched Aβ‐ controls, performance improves substantially (i.e. a practice effect)....
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crwiley:10.1002/alz.045901 2024-03-17T08:59:44+00:00 Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease Neuropsychology: Neuropsychological correlates of pathology — Novel and standard cognitive markers of disease Lim, Yen Ying Baker, Jenalle E. Bruns, Loren Mills, Andrea Fowler, Christopher J. Fripp, Jurgen Rainey‐Smith, Stephanie R. Ames, David Masters, Colin L. Maruff, Paul T. 2020 http://dx.doi.org/10.1002/alz.045901 https://onlinelibrary.wiley.com/doi/pdf/10.1002/alz.045901 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/alz.045901 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Alzheimer's & Dementia volume 16, issue S6 ISSN 1552-5260 1552-5279 Psychiatry and Mental health Cellular and Molecular Neuroscience Geriatrics and Gerontology Neurology (clinical) Developmental Neuroscience Health Policy Epidemiology journal-article 2020 crwiley https://doi.org/10.1002/alz.045901 2024-02-22T01:46:12Z Abstract Background Reports from longer studies of preclinical Alzheimer’s disease (i.e., Aβ+ cognitively normal older adults) now show that performance on memory tests remains stable across re‐assessments, whereas in matched Aβ‐ controls, performance improves substantially (i.e. a practice effect). Such observations have led to proposals that the absence of expected practice effects may provide a superior cognitive marker of Aβ+ in older adults. However, an alternative explanation may be that disruption to MTL areas in preclinical AD manifest more strongly as deficits in learning than as a progressive decline in memory recall. Using a test designed specifically to measure learning over days, we aimed to determine the extent to which deficits in learning over 6 days are associated with Aβ+ and hippocampal volume in CN adults. Method Eighty CN older adults who had undergone positron emission tomography (PET) neuroimaging to determine Aβ status (n=42 Aβ‐ and 38 Aβ+), magnetic resonance imaging (MRI) to determine hippocampal and ventricular volume and repeated assessment of memory were recruited from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study. Participants completed the Online Repeatable Cognitive Assessment‐Language Learning Test (ORCA‐LLT), which required they learn associations between 50 Chinese characters and their English language equivalents over 6 days. ORCA‐LLT assessments were supervised on the first day, and were completed remotely online for all remaining days. Result Learning curves in the Aβ+ CNs were significantly worse than those in matched Aβ‐ CNs, with the magnitude of this difference very large (d=2.16, p <.001) (Figure 1), and greater than differences between these groups for memory decline since their enrolment in AIBL (d=0.52, p =.021), or memory impairment at their most recent visit. In Aβ+ CN adults, slower rates of learning were associated with smaller hippocampal, and larger ventricular volumes. Conclusion These results suggest that in CNs, Aβ+ is associated more ... Article in Journal/Newspaper Orca Wiley Online Library Alzheimer's & Dementia 16 S6 |
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Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
topic |
Psychiatry and Mental health Cellular and Molecular Neuroscience Geriatrics and Gerontology Neurology (clinical) Developmental Neuroscience Health Policy Epidemiology |
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Psychiatry and Mental health Cellular and Molecular Neuroscience Geriatrics and Gerontology Neurology (clinical) Developmental Neuroscience Health Policy Epidemiology Lim, Yen Ying Baker, Jenalle E. Bruns, Loren Mills, Andrea Fowler, Christopher J. Fripp, Jurgen Rainey‐Smith, Stephanie R. Ames, David Masters, Colin L. Maruff, Paul T. Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease |
topic_facet |
Psychiatry and Mental health Cellular and Molecular Neuroscience Geriatrics and Gerontology Neurology (clinical) Developmental Neuroscience Health Policy Epidemiology |
description |
Abstract Background Reports from longer studies of preclinical Alzheimer’s disease (i.e., Aβ+ cognitively normal older adults) now show that performance on memory tests remains stable across re‐assessments, whereas in matched Aβ‐ controls, performance improves substantially (i.e. a practice effect). Such observations have led to proposals that the absence of expected practice effects may provide a superior cognitive marker of Aβ+ in older adults. However, an alternative explanation may be that disruption to MTL areas in preclinical AD manifest more strongly as deficits in learning than as a progressive decline in memory recall. Using a test designed specifically to measure learning over days, we aimed to determine the extent to which deficits in learning over 6 days are associated with Aβ+ and hippocampal volume in CN adults. Method Eighty CN older adults who had undergone positron emission tomography (PET) neuroimaging to determine Aβ status (n=42 Aβ‐ and 38 Aβ+), magnetic resonance imaging (MRI) to determine hippocampal and ventricular volume and repeated assessment of memory were recruited from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study. Participants completed the Online Repeatable Cognitive Assessment‐Language Learning Test (ORCA‐LLT), which required they learn associations between 50 Chinese characters and their English language equivalents over 6 days. ORCA‐LLT assessments were supervised on the first day, and were completed remotely online for all remaining days. Result Learning curves in the Aβ+ CNs were significantly worse than those in matched Aβ‐ CNs, with the magnitude of this difference very large (d=2.16, p <.001) (Figure 1), and greater than differences between these groups for memory decline since their enrolment in AIBL (d=0.52, p =.021), or memory impairment at their most recent visit. In Aβ+ CN adults, slower rates of learning were associated with smaller hippocampal, and larger ventricular volumes. Conclusion These results suggest that in CNs, Aβ+ is associated more ... |
format |
Article in Journal/Newspaper |
author |
Lim, Yen Ying Baker, Jenalle E. Bruns, Loren Mills, Andrea Fowler, Christopher J. Fripp, Jurgen Rainey‐Smith, Stephanie R. Ames, David Masters, Colin L. Maruff, Paul T. |
author_facet |
Lim, Yen Ying Baker, Jenalle E. Bruns, Loren Mills, Andrea Fowler, Christopher J. Fripp, Jurgen Rainey‐Smith, Stephanie R. Ames, David Masters, Colin L. Maruff, Paul T. |
author_sort |
Lim, Yen Ying |
title |
Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease |
title_short |
Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease |
title_full |
Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease |
title_fullStr |
Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease |
title_full_unstemmed |
Deficits in learning are greater than memory dysfunction in preclinical Alzheimer’s disease |
title_sort |
deficits in learning are greater than memory dysfunction in preclinical alzheimer’s disease |
publisher |
Wiley |
publishDate |
2020 |
url |
http://dx.doi.org/10.1002/alz.045901 https://onlinelibrary.wiley.com/doi/pdf/10.1002/alz.045901 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/alz.045901 |
genre |
Orca |
genre_facet |
Orca |
op_source |
Alzheimer's & Dementia volume 16, issue S6 ISSN 1552-5260 1552-5279 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/alz.045901 |
container_title |
Alzheimer's & Dementia |
container_volume |
16 |
container_issue |
S6 |
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1793770548204929024 |