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Synapse loss in frontal cortex biopsies in Alzheimer's disease: Correlation with cognitive severity
Steven T. DeKosky, Stephen W. Scheff. Annals of Neurology, 1990-05-01
Topic: Amyloid, tau and blood-test diagnosis
Ultrastructural studies of biopsied cortical tissue from the right frontal lobe of 8 patients with mild to moderate Alzheimer's disease (AD) revealed that the number of synapses in lamina III of Brodmann's area 9 was significantly decreased when compared with the number in age-matched control brains (n = 9; postmortem time, less than 13 hours). Further decline in synaptic number was seen in age-matched autopsied AD specimens. In the AD brains there was significant enlargement of the mean apposition length, which correlated with degree of synapse loss; as synapse density declined, synapse size increased. The enlargement of synapses, coupled with the decrease in synaptic number, allowed the total synaptic contact area per unit volume to remain stable in the patients who underwent biopsy. In autopsied subjects who had AD, there was no further enlargement of mean synaptic contact area. There was a significant correlation between synapse counts and scores on the Mini-Mental State examination in the patients who underwent biopsy. Lower mental status scores were associated with greater loss of synapses. Choline acetyltransferase activity was significantly decreased in the biopsied group and declined further in the autopsied specimens of AD. There was no relationship between choline acetyltransferase activity and scores on the Mini-Mental State examination or synapse number. There is evidence of neural plasticity in the AD neuropil; synaptic contact size increased in patients who had biopsy and possibly compensated for the numerical loss of synapses. But by end stage of the disease, the ability of the cortex to compensate was exceeded and both synapse number and synaptic contact area declined.(ABSTRACT TRUNCATED AT 250 WORDS)
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
DeKosky, S. T., & Scheff, S. W. (1990). Synapse loss in frontal cortex biopsies in Alzheimer's disease: Correlation with cognitive severity. Annals of Neurology. https://doi.org/10.1002/ana.410270502
Vancouver
DeKosky ST, Scheff SW. Synapse loss in frontal cortex biopsies in Alzheimer's disease: Correlation with cognitive severity. Annals of Neurology. 1990. doi:10.1002/ana.410270502. PMID: 2360787.
BibTeX
@article{dekosky1990-2360787,
author = {DeKosky, Steven T. and Scheff, Stephen W.},
title = {{Synapse loss in frontal cortex biopsies in Alzheimer's disease: Correlation with cognitive severity}},
journal = {Annals of Neurology},
year = {1990},
doi = {10.1002/ana.410270502},
pmid = {2360787},
url = {https://doi.org/10.1002/ana.410270502}
}
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.
Why it matters
Frontal lobe biopsies from 8 people with mild to moderate Alzheimer's had fewer synapses than control brains, and lower Mini-Mental State scores went with greater synapse loss. Remaining synapses were larger, which the authors see as the brain partly compensating, a capacity that was exceeded by end stage.
How this study scored 54/100
Published in a leading specialty 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 strength of evidence, so that was left out: it earned 51 of the 95 points we could judge it on, which is 54 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Annals of Neurology) |
| Journal's citation record | 3 / 4 | Annals of Neurology: journal h-index 437 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | — / 5 | No evidence rating recorded — left out of this score |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1990 — 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 | 7 / 7 | Cited 2,380 times (OpenAlex, 2026-10-10) |
| Citations per year | 5 / 5 | 62.6 citations a year over 38 year(s) since 1990 |
| Impact for its field and year | 5 / 6 | Cited 22.0× 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 | 4 / 4 | Cited 271 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Stephen W. Scheff: h-index 86 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | University of Kentucky: institution h-index 824 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 2360787) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 51 / 95 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 51 of the 95 points we could judge it on is 54 out of 100. |
| Total | 54 / 100 | — |
What each of these 20 components measures, and what this score is not →
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