27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. 2 key findings →
Design: meta-analysis Participants: 12,826 Evidence: high
Full summary, score breakdown and related studies → Original source
Identifying genetic variants influencing human brain structures may reveal new biological mechanisms underlying cognition and neuropsychiatric illness. 2 key findings →
Design: meta-analysis Participants: 21,151 Evidence: high
Full summary, score breakdown and related studies → Original source
Lower intakes of nutrient-dense foods and higher intakes of unhealthy foods are each independently associated with smaller left hippocampal volume. 3 key findings →
Design: meta-analysis Participants: 255 Evidence: high
Full summary, score breakdown and related studies → Original source
The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. 3 key findings →
Participants: 33,536 Evidence: low
Full summary, score breakdown and related studies → Original source
The hippocampus shrinks in late adulthood, leading to impaired memory and increased risk for dementia. 4 key findings →
Design: randomized controlled trial Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
Our study is not subject to the biases of meta-analyses of published data, and it represents an important milestone in an ongoing collaborative effort to examine the neurobiological underpinnings of PTSD and the brain's response to trauma. 2 key findings →
Design: meta-analysis Participants: 1,868 Evidence: high
Full summary, score breakdown and related studies → Original source
Hippocampal volume loss in first episode depression is consistent with a neurodevelopmental model of depression, advocating hippocampal structure as a potential diagnostic neurobiomarker for depression. 2 key findings →
Design: meta-analysis Participants: 191 Evidence: high
Full summary, score breakdown and related studies → Original source
Furthermore, hippocampal subfields susceptible to atrophy in AD were protected by PRT revealing an elimination of long-term atrophy in the left subiculum, and attenuation of atrophy in left CA1 and dentate gyrus when compared to SHAM+SHAM (p = 0.023, p = 0.020 and p = 0.027). 4 key findings →
Evidence: high
Full summary, score breakdown and related studies → Original source
Hippocampal volume is a marker of brain health and is reduced with aging and neurological disease. 4 key findings →
Design: meta-analysis Participants: 23 Evidence: high
Full summary, score breakdown and related studies → Original source
Average volumetric changes are close to the limit of detection by MRI methods. 2 key findings →
Design: systematic review Participants: 1,424 Evidence: high
Full summary, score breakdown and related studies → Original source
Hippocampal volume increase in response to aerobic exercise has been consistently observed in animal models. 3 key findings →
Design: systematic review Participants: 737 Evidence: high
Full summary, score breakdown and related studies → Original source
Over the last decade a significant number of studies have reported smaller hippocampal volume in individuals with symptoms of post-traumatic stress disorder (PTSD) relative to control groups, and in some cases hemispheric asymmetries in this effect have been noted. 4 key findings →
Design: systematic review Participants: 13 Evidence: high
Full summary, score breakdown and related studies → Original source
Conjugated equine estrogens with or without MPA are associated with greater brain atrophy among women aged 65 years and older; however, the adverse effects are most evident in women experiencing cognitive deficits before initiating hormone therapy. 3 key findings →
Evidence: high
Full summary, score breakdown and related studies → Original source
The meta-analyses revealed structural brain abnormalities associated with PTSD and trauma and suggest that global brain volume reductions distinguish PTSD from major depression. 5 key findings →
Design: meta-analysis Participants: 113 Evidence: high
Full summary, score breakdown and related studies → Original source
Hippocampal volume is reduced in patients with unipolar depression, maybe as a consequence of repeated periods of major depressive disorder. 2 key findings →
Design: systematic review Participants: 351 Evidence: high
Full summary, score breakdown and related studies → Original source
These findings are consistent with smaller hippocampal volume in adult subjects with chronic PTSD. 5 key findings →
Design: meta-analysis Participants: 133 Evidence: high
Full summary, score breakdown and related studies → Original source
Posttraumatic stress disorder (PTSD) is a debilitating condition associated with mild to moderate cognitive impairment and with a prevalence rate of up to 22% in veterans. 5 key findings →
Design: systematic review Participants: 846 Evidence: high
Full summary, score breakdown and related studies → Original source
Relative to control subjects, patients had significantly smaller HCVs (standardized mean difference = -0.32 [95% confidence interval, -0.44 to -0.19]). 5 key findings →
Design: cohort study Participants: 2,702 Evidence: moderate
Full summary, score breakdown and related studies → Original source
Those with high baseline stress levels are more likely to develop mild cognitive impairment (MCI) and Alzheimer's Disease (AD). 3 key findings →
Participants: 14 Evidence: high
Full summary, score breakdown and related studies → Original source
The current study suggests that the degree of HPA hyperactivity can vary considerably across patient groups. 5 key findings →
Participants: 18,454 Evidence: low
Full summary, score breakdown and related studies → Original source Full text may need a subscription
Early identification of patterns of abnormality is of fundamental importance for detecting disease onset and tracking progression. 2 key findings →
Design: longitudinal study Participants: 1,017 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
These results indicate that in both healthy subjects and patients with schizophrenia hippocampal volume is plastic in response to aerobic exercise. 3 key findings →
Evidence: high
Full summary, score breakdown and related studies → Original source
We aimed to investigate whether hippocampal TDP-43 is associated with increased rates of hippocampal atrophy. 4 key findings →
Design: longitudinal study Participants: 205 Evidence: moderate
Full summary, score breakdown and related studies → Original source
This study found that the prevalence of maternal psychological distress in healthy, well-educated, and employed pregnant women was high, underappreciated, and associated with impaired fetal brain biochemistry and hippocampal growth as well as accelerated cortical folding. 5 key findings →
Design: cohort study Participants: 193 Evidence: moderate
Full summary, score breakdown and related studies → Original source
The objective of this study was to examine exercise effects on global brain volume, hippocampal volume, and cortical thickness in schizophrenia patients and healthy controls. 2 key findings →
Design: randomized controlled trial Evidence: high
Full summary, score breakdown and related studies → Original source
9 of the 492 studies in this tag, picked by a fixed rule (a hash of each study's address), not by score or date; each page of this list shows a different 9. The same 9 appear here every time.
Free full text links and the Full text may need a subscription label come from Unpaywall, Europe PMC and OpenAlex records of free copies, checked 10 Oct 2026. A study with neither is unknown, not paywalled. Show only studies that are free to read
This is alzhub's own score. It is not an official metric, not an impact factor, and no journal, publisher or ranking body endorses it. We built it so that a reader who is not a scientist can tell a landmark trial from a conference abstract without having to already know the difference. Every point comes from one of 20 components, all of them printed on the study itself, so you can disagree with our arithmetic rather than having to trust the total.
Journals are placed in ordered tiers, never given a numeric impact factor — we could not verify current impact factors from a source we control, and an invented one would be worse than none. Tier 1 is the top-tier general journals (NEJM, The Lancet, JAMA, Nature, Science, Nature Medicine); tier 2 is the leading specialty journals; tier 3 is every other peer-reviewed journal. A separate part scores how much the journal's own papers are cited, which tells the tier-3 journals apart.
Two rules we don't bend. First, we never fill in a missing value: if a record does not state a sample size or a design, that component scores zero, and if we simply have no data for a part, such as a citation count, that part is left out and the study is scored on the parts we could check. The study card says which. Second, anything that is not a peer-reviewed article is capped at 16/100 and carries a warning chip — so a conference abstract or a company press release can never outrank a peer-reviewed paper, no matter how good it looks.
We rank a rigorous null result — a good trial showing that something does not work — above an early positive finding. Someone deciding whether to buy a supplement is served by that, and the rigour is already counted by the design and journal components.
The score is computed from the published data alone and is reproducible: the same file always yields the same numbers.
See the whole rubric drawn out → — four charts covering all 27,380 studies: how the scores are spread and where the cap bites, which of the 20 components the library is strong and weak on, which subjects rest on stronger evidence, and what kinds of study each subject is actually built from.
This is a large sample of the Alzheimer's literature, not an exhaustive index of it. It holds 27,380 records, built mostly from automated pulls of Europe PMC (60.6% of the library) and OpenAlex (18.6%), plus smaller pulls from PubMed, Crossref and medRxiv. If a study, a drug, or a finding isn't here, that is not evidence it doesn't exist in the literature — it may simply not have been pulled in yet.
1,032 records (3.8% of the library) are not peer-reviewed — 962 of those are preprints posted before any journal review, and the rest are conference abstracts, regulatory notices and reports. Every study card on this page states its status plainly, and the score above is capped for anything that isn't a peer-reviewed article.
See the full, machine-readable breakdown of this library's coverage →