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Quantitative assessment of synaptic density in the outer molecular layer of the hippocampal dentate gyrus in Alzheimer's disease
Scheff SW, Sparks DL, Price DA.. Dementia (Basel, Switzerland), 1996-07-01
Topic: Amyloid, tau and blood-test diagnosis
We quantified the synaptic density in the outer molecular layer of the hippocampal dentate gyrus. Autopsy material from 9 individuals with Alzheimer disease (AD) were compared to 10 age-matched, postmortem-matched controls without dementia, using standard electron microscopy. Statistical analyses showed a significant change in the density of synapses between controls and AD subjects. There was a significant decline in the width of the entire molecular layer in the AD material. Synaptic density showed a significant correlation with synaptic apposition length in both AD and control groups. As the number of synapses declined, the synaptic apposition length increased. The decline in density of synapses in the AD group might reflect the degree of neuronal loss in the entorhinal cortex. Such a loss in synaptic connectivity could play a key role in memory-related problems associated with AD.
Key findings
- Autopsy material from 9 individuals with Alzheimer disease (AD) were compared to 10 age-matched, postmortem-matched controls without dementia, using standard electron microscopy.
- Statistical analyses showed a significant change in the density of synapses between controls and AD subjects.
- There was a significant decline in the width of the entire molecular layer in the AD material.
- Synaptic density showed a significant correlation with synaptic apposition length in both AD and control groups.
- Such a loss in synaptic connectivity could play a key role in memory-related problems associated with AD.
Why it matters
In brain tissue examined after death from 9 people with Alzheimer's disease and 10 age-matched people without dementia, electron microscopy found fewer synapses in the outer molecular layer of the hippocampal dentate gyrus, and the whole molecular layer was thinner. Where synapses were fewer, the remaining contacts were longer. The authors suggest this loss of connections "could play a key role in memory-related problems," but the study did not measure memory and does not test any treatment or prevention.
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Study details
- Evidence strengthLow
How this study scored 34/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, so that was left out: it earned 33 of the 96 points we could judge it on, which is 34 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Dementia (Basel, Switzerland)) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1996 — older than 20 years, still counted |
| 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 | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 4 / 7 | Cited 95 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 3.0 citations a year over 32 year(s) since 1996 |
| Impact for its field and year | 1 / 6 | Cited 0.9× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 6 other studies in this library |
| Still being cited | 1 / 4 | Cited 3 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author DOUGLAS A. PRICE: h-index 25 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | University of Kentucky: institution h-index 824 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 8835888) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 33 / 96 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 33 of the 96 points we could judge it on is 34 out of 100. |
| Total | 34 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Scheff, S. W., Sparks, D. L., & Price, D. A. (1996). Quantitative assessment of synaptic density in the outer molecular layer of the hippocampal dentate gyrus in Alzheimer's disease. Dementia (Basel, Switzerland). https://doi.org/10.1159/000106884
Vancouver
Scheff SW, Sparks DL, Price DA. Quantitative assessment of synaptic density in the outer molecular layer of the hippocampal dentate gyrus in Alzheimer's disease. Dementia (Basel, Switzerland). 1996. doi:10.1159/000106884. PMID: 8835888.
BibTeX
@article{scheff1996-8835888,
author = {Scheff, S. W. and Sparks, D. L. and Price, D. A.},
title = {{Quantitative assessment of synaptic density in the outer molecular layer of the hippocampal dentate gyrus in Alzheimer's disease}},
journal = {Dementia (Basel, Switzerland)},
year = {1996},
doi = {10.1159/000106884},
pmid = {8835888},
url = {https://doi.org/10.1159/000106884}
}
Later studies that cite this one
6 studies in the alzhub library list this one in their references.