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Effects of donepezil on verbal memory after semantic processing in healthy older adults
FitzGerald DB, Crucian GP, Mielke JB, Shenal BV, Burks D, Womack KB, Ghacibeh G, Drago V et al.. Cognitive and behavioral neurology : official journal of the Society for Behavioral and Cognitive Neurology, 2008-06-01
Topic: Risk, prevention and care in population studies
Objective To learn if acetylcholinesterase inhibitors alter verbal recall by improving semantic encoding in a double-blind randomized placebo-controlled trial. Background Cholinergic supplementation has been shown to improve delayed recall in adults with Alzheimer disease. With functional magnetic resonance imaging, elderly adults, when compared with younger participants, have reduced cortical activation with semantic processing. There have been no studies investigating the effects of cholinergic supplementation on semantic encoding in healthy elderly adults. Method Twenty elderly participants (mean age 71.5, SD+/-5.2) were recruited. All underwent memory testing before and after receiving donepezil (5 mg, n=11 or 10 mg, n=1) or placebo (n=8) for 6 weeks. Memory was tested using a Levels of Processing task, where a series of words are presented serially. Subjects were either asked to count consonants in a word (superficially process) or decide if the word was "pleasant" or "unpleasant" (semantically process). Results After 6 weeks of donepezil or placebo treatment, immediate and delayed recall of superficially and semantically processed words was compared with baseline performance. Immediate and delayed recall of superficially processed words did not show significant changes in either treatment group. With semantic processing, both immediate and delayed recall performance improved in the donepezil group. Conclusions Our results suggest that when using semantic encoding, older normal subjects may be aided by anticholinesterase treatment. However, this treatment does not improve recall of superficially encoded words.
Key findings
- With functional magnetic resonance imaging, elderly adults, when compared with younger participants, have reduced cortical activation with semantic processing.
- Results After 6 weeks of donepezil or placebo treatment, immediate and delayed recall of superficially and semantically processed words was compared with baseline performance.
- Immediate and delayed recall of superficially processed words did not show significant changes in either treatment group.
- Conclusions Our results suggest that when using semantic encoding, older normal subjects may be aided by anticholinesterase treatment.
Why it matters
In 20 healthy older adults, 6 weeks of donepezil did not significantly change recall of superficially processed words in either treatment group. This small study looked at memory in healthy people, not at treating or preventing Alzheimer's disease.
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Study details
- Evidence strengthHigh
How this study scored 56/100
Published in a peer-reviewed journal, and it is a randomised controlled trial. Scored zero for sample size and effect reported because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Cognitive and behavioral neurology : official journal of the Society for Behavioral and Cognitive Neurology) |
| Journal's citation record | 0 / 4 | Cognitive and Behavioral Neurology: journal h-index 66 (OpenAlex, 2026-10-29) |
| Study design | 11 / 12 | A randomised controlled trial (from PubMed type “Randomized Controlled Trial”) |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2008 — within 20 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (pubmed indexes it as a clinical or observational study) |
| Randomised / blinded | 2 / 2 | Randomised and blinded or placebo-controlled (as stated in the record) |
| Times cited | 4 / 7 | Cited 43 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 2.1 citations a year over 20 year(s) since 2008 |
| Impact for its field and year | 3 / 6 | Cited 3.3× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 0 / 4 | Cited 2 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Kenneth M. Heilman: h-index 103 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | The University of Texas Southwestern Medical Center: institution h-index 1,356 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 8 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 18541979) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 56 / 100 | — |
What each of these 20 components measures, and what this score is not →
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May need a subscription Unpaywall, Europe PMC and OpenAlex found no free copy of the full text (checked 10 Oct 2026), so the publisher may charge for it. The PubMed abstract is free.
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Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
FitzGerald, D. B., Crucian, G. P., Mielke, J. B., Shenal, B. V., Burks, D., Womack, K. B., et al. (2008). Effects of donepezil on verbal memory after semantic processing in healthy older adults. Cognitive and behavioral neurology : official journal of the Society for Behavioral and Cognitive Neurology. https://doi.org/10.1097/wnn.0b013e3181799df1
Vancouver
FitzGerald DB, Crucian GP, Mielke JB, Shenal BV, Burks D, Womack KB, et al. Effects of donepezil on verbal memory after semantic processing in healthy older adults. Cognitive and behavioral neurology : official journal of the Society for Behavioral and Cognitive Neurology. 2008. doi:10.1097/wnn.0b013e3181799df1. PMID: 18541979.
BibTeX
@article{fitzgerald2008-18541979,
author = {FitzGerald, D. B. and Crucian, G. P. and Mielke, J. B. and Shenal, B. V. and Burks, D. and Womack, K. B. and Ghacibeh, G. and Drago, V. and others},
title = {{Effects of donepezil on verbal memory after semantic processing in healthy older adults}},
journal = {Cognitive and behavioral neurology : official journal of the Society for Behavioral and Cognitive Neurology},
year = {2008},
doi = {10.1097/wnn.0b013e3181799df1},
pmid = {18541979},
url = {https://doi.org/10.1097/wnn.0b013e3181799df1}
}
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