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Volume and number of neurons of the human hippocampal formation in normal aging and Alzheimer's disease
Simić G, Kostović I, Winblad B, Bogdanović N.. The Journal of comparative neurology, 1997-03-01
Topic: Amyloid, tau and blood-test diagnosis
In order to observe changes owing to aging and Alzheimer's disease (AD) in the volumes of subdivisions of the hippocampus and the number of neurons of the hippocampal formation, 18 normal brains from subjects who died of nonneurological causes and had no history of long-term illness or dementia (ten of these brains comprised the aged control group) and 13 AD brains were analyzed. An optimized design for sampling, measuring volume by using the Cavalieri principle, and counting the number of neurons by using the optical disector was implemented on 50 microns-thick cresyl-violet sections. The mean total volume of the principal subdivisions of the hippocampal formation (fascia dentata, hilus, CA3-2, CA1, and subiculum) showed a negative correlation with age in normal subjects (r = -0.56, 2P < 0.05), and a 32% mean reduction in the AD group compared with controls (P < 0.001). This finding supports the measurement of the coronal cross-sectional area and the volume of the hippocampal formation in the clinical diagnosis of AD. There was an inverse relationship between the age of normal subjects and the number of neurons in CA1 (r = -0.84, 2P < 0.0001) and subiculum (r = -0.49, 2P < 0.05) but not in other subdivisions. Pronounced AD-related reductions in neuron number were found only in the subiculum and the fascia dentata. Compared with controls, both losses represented 23% of neurons (P < 0.05). These results 1) confirm that AD is a qualitatively different process from normal aging and 2) reveal the regional selectivity of neuron loss within the hippocampal formation in aging and AD, which may be relevant to understanding the mechanisms involved in the neuron loss associated with the two processes.
Key findings
- The mean total volume of the principal subdivisions of the hippocampal formation (fascia dentata, hilus, CA3-2, CA1, and subiculum) showed a negative correlation with age in normal subjects (r = -0.56, 2P < 0.05), and a 32% mean reduction in the AD group compared with controls (P < 0.001).
- Compared with controls, both losses represented 23% of neurons (P < 0.05).
- These results 1) confirm that AD is a qualitatively different process from normal aging and 2) reveal the regional selectivity of neuron loss within the hippocampal formation in aging and AD, which may be relevant to understanding the mechanisms involved in the neuron loss associated with the two processes.
Why it matters
This brain tissue study found that the hippocampus was about 32% smaller in people with Alzheimer's disease than in controls, with neuron loss in specific regions, and that some shrinkage also occurred with normal aging. It supports using hippocampal volume in diagnosis but does not offer a treatment or cure.
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Study details
- Study designcross-sectional
- Evidence strengthLow
How this study scored 49/100
Published in a peer-reviewed journal, and it is a snapshot of people at one point in time. Scored zero for sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on senior author's track record, so that was left out: it earned 47 of the 96 points we could judge it on, which is 49 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (The Journal of comparative neurology) |
| Journal's citation record | 3 / 4 | The Journal of Comparative Neurology: journal h-index 431 (OpenAlex, 2026-10-29) |
| Study design | 4 / 12 | A snapshot of people at one point in time |
| 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 | 1997 — 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 | 6 / 7 | Cited 520 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 16.8 citations a year over 31 year(s) since 1997 |
| Impact for its field and year | 4 / 6 | Cited 11.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 9 other studies in this library |
| Still being cited | 2 / 4 | Cited 33 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | — / 4 | OpenAlex's profile for last-listed author Nenad Bogdanovi holds only 1 work(s), too few to judge a track record — left out of this score |
| Institution's track record | 1 / 3 | Karolinska Institutet: institution h-index 1,477 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9067838) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 47 / 96 | Scored on 19 of 20 parts. We have no data for the rest, so they are left out: 47 of the 96 points we could judge it on is 49 out of 100. |
| Total | 49 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1002/(sici)1096-9861(19970324)379:4<482::aid-cne2>3.0.co;2-z
- PubMed: 9067838
- Original source →
- Free full text: The Journal of Comparative Neurology →
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
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
Simić, G., Kostović, I., Winblad, B., & Bogdanović, N. (1997). Volume and number of neurons of the human hippocampal formation in normal aging and Alzheimer's disease. The Journal of comparative neurology. https://doi.org/10.1002/(sici)1096-9861(19970324)379:4<482::aid-cne2>3.0.co;2-z
Vancouver
Simić G, Kostović I, Winblad B, Bogdanović N. Volume and number of neurons of the human hippocampal formation in normal aging and Alzheimer's disease. The Journal of comparative neurology. 1997. doi:10.1002/(sici)1096-9861(19970324)379:4<482::aid-cne2>3.0.co;2-z. PMID: 9067838.
BibTeX
@article{simic1997-9067838,
author = {Simić, G. and Kostović, I. and Winblad, B. and Bogdanović, N.},
title = {{Volume and number of neurons of the human hippocampal formation in normal aging and Alzheimer's disease}},
journal = {The Journal of comparative neurology},
year = {1997},
doi = {10.1002/(sici)1096-9861(19970324)379:4<482::aid-cne2>3.0.co;2-z},
pmid = {9067838},
url = {https://doi.org/10.1002/(sici)1096-9861(19970324)379:4<482::aid-cne2>3.0.co;2-z}
}
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