Evidence map›Paper›PMID 41144662›Full record

ArticleProceedings of the National Academy of Sciences of the United States of America2025

Quantitative MRI of the hippocampus reveals microstructural trajectories of aging and Alzheimer's disease pathology.

Alfie Wearn, Christine L Tardif, Ilana R Leppert, Giulia Baracchini, Colleen Hughes, Jennifer Tremblay-Mercier, John Breitner, Judes Poirier, Sylvia Villeneuve, Boris C Bernhardt and 3 more

Abstract read
In one paragraph

Article in Proceedings of the National Academy of Sciences of the United States of America, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed.

  1. Article
  2. Article
  3. Article
  4. Review
  5. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

13 authors.

Alfie WearnMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0001-7699-648X
Christine L TardifMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0001-8356-6808
Ilana R LeppertMcConnell Brain Imaging Centre, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0001-7672-0918
Giulia BaracchiniMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.
Colleen HughesMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0002-0632-4060
Jennifer Tremblay-MercierDouglas Mental Health University Institute, Verdun, QC H4H 1R3, Canada.
John BreitnerDouglas Mental Health University Institute, Verdun, QC H4H 1R3, Canada.
Judes PoirierDouglas Mental Health University Institute, Verdun, QC H4H 1R3, Canada.ORCID 0000-0002-8018-4545
Sylvia VilleneuveMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0003-2338-0467
Boris C BernhardtMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0001-9256-6041
Gary R TurnerDepartment of Psychology, York University, Toronto, ON M3J 1P3, Canada.ORCID 0000-0001-7232-8994
R Nathan SprengMontreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, QC H3A 2B4, Canada.ORCID 0000-0003-1530-8916
PREVENT-AD Research Group

Funding

Investigating the impact of loneliness on brain aging and pre-symptomatic Alzheimer's disease progressionR01AG068563 · NIA · MCGILL UNIVERSITY · PI BZDOK, DANILO, SPRENG, ROBERT NATHAN · 2020 to 2024
$2.3M
Alzheimer's Association (AA) AARG-22-927100HHS | NIH (NIH) AG068563NIA NIH HHS R01 AG068563
6 · The paper itself

Abstract

Hippocampal degeneration is a feature of both normal aging and Alzheimer's disease (AD). Prior to macroscopic degeneration, microstructural changes occur such as demyelination, iron deposition, or subtle atrophy, which can be characterized in vivo using MRI. We topographically mapped measures of microstructure and macrostructure across the unfolded surface of the hippocampus in 224 healthy older adults at risk for AD (aged 57 to 87) and 37 younger adults (aged 18 to 37). We describe three spatial regions of unique structural covariance between four parameters sensitive to microstructural tissue properties (R1, MTsat, R2*, PD) and macrostructure (surface thickness), with high convergence with previous spatial segmentations. We demonstrate both cross-sectional and longitudinal associations of microstructure with healthy aging across the lifespan, AD pathological hallmarks, genetic risk, and cognition. These associations had subtle variations across different spatial areas of the hippocampus. We report associations between age and qMRI measures sensitive to macromolecular concentration (R1, MTsat) and paramagnetic susceptibility (R2*), consistent with mechanisms of demyelination and increased iron deposition as key hallmarks of the aging hippocampus and in presymptomatic stages of AD. qMRI measures did not explain more variance in delayed recall than global PET measures, suggesting variation in cognitive performance in aging and incipient AD is influenced by factors beyond hippocampal microstructure. We demonstrate the utility of quantitative MRI to provide greater insight into hippocampal health compared to typical macrostructural measures through "in vivo histology," opening a window to understanding neuropathological mechanisms in the earliest stages of age- and disease-related neurodegeneration.

Indexed as

AgingAlzheimer DiseaseHippocampusMagnetic Resonance ImagingAdolescentAdultAgedAged, 80 and overCross-Sectional StudiesFemaleHumansMaleMiddle AgedYoung AdultagingAlzheimer’s diseasehippocampusmicrostructureMRI

Identifiers

PMID41144662
PMCPMC12595451

What OpenQuestion holds

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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.