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Dysfunctional default mode and visual networks underlie cognitive deficits in dementia with Lewy bodies: a resting-state fMRI study
Su Zhou, Mengran Liu, Jun Kuai, Tingting Yi, Yuechang Zheng, Xinran Bao, Jiyu Ji. Frontiers in Aging Neuroscience, 2025-11-19
Topic: Brain proteins, microglia and lab models
Objective To characterize abnormal functional connectivity in dementia with Lewy bodies (DLB) and its association with cognitive impairment using resting-state functional magnetic resonance imaging (rs-fMRI). Methods Sixty-eight DLB patients and 38 age-, sex-, and education-matched healthy controls underwent neuropsychological assessments (MoCA, MMSE) and rs-fMRI. Imaging analyses included seed-based functional connectivity (sFC), independent component analysis (ICA), regional homogeneity (ReHo), fractional amplitude of low-frequency fluctuations (fALFF), and graph-theoretical network metrics (small-worldness, global/local efficiency). Results DLB patients exhibited significantly reduced FC in the default mode network (DMN) and visual network, including PCC–AG ( P < 0.001) and PCC–mPFC ( P < 0.001). ReHo and fALFF indicated decreased local neural synchronization and low-frequency activity in the posterior occipital lobe (fALFF: P = 0.004), angular gyrus (fALFF: P = 0.001), left temporal pole (fALFF: P < 0.001), left parietal (ReHo: P < 0.001), and posterior cerebellar lobe (ReHo: P < 0.001). Graph theory revealed impaired global network topology in DLB, with decreased small-worldness ( P < 0.001) and global efficiency ( P < 0.001). PCC–AG connectivity positively correlated with the MoCA total score ( r = 0.53, P < 0.001), attention ( r = 0.46, P < 0.001), executive ( r = 0.41, P < 0.001), and language function ( r = 0.34, P < 0.001). Posterior occipital fALFF and left parietal ReHo showed significant positive correlations with multiple cognitive domains, including visuospatial ability ( r = 0.34, P < 0.001 for fALFF; r = 0.42, P < 0.001 for ReHo) and memory ( r = 0.45, P < 0.001 for fALFF; r = 0.27, P = 0.006 for ReHo). A combined model of PCC–AG connectivity, fALFF, and small-worldness predicted 42% of MoCA variance ( R 2 = 0.42, P < 0.001). Conclusion DLB is characterized by DMN and visual network dysfunction, disrupted local neural activity, and impaired global network integration. These rs-fMRI metrics may serve as potential biomarkers for cognitive deficits in DLB.
Key findings
- Results DLB patients exhibited significantly reduced FC in the default mode network (DMN) and visual network, including PCC–AG ( P < 0.001) and PCC–mPFC ( P < 0.001).
- Graph theory revealed impaired global network topology in DLB, with decreased small-worldness ( P < 0.001) and global efficiency ( P < 0.001).
- Posterior occipital fALFF and left parietal ReHo showed significant positive correlations with multiple cognitive domains, including visuospatial ability ( r = 0.34, P < 0.001 for fALFF; r = 0.42, P < 0.001 for ReHo) and memory ( r = 0.45, P < 0.001 for fALFF; r = 0.27, P = 0.006 for ReHo).
Why it matters
In dementia with Lewy bodies, brain imaging showed reduced connectivity in the default mode and visual networks and impaired global network organization, which correlated with cognitive test scores. This helps explain how brain network changes relate to cognitive deficits, but it is not a treatment or cure.
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 senior author's track 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 (Frontiers in Aging Neuroscience) |
| Journal's citation record | 2 / 4 | Frontiers in Aging Neuroscience: journal h-index 174 (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 | 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 | 4 / 5 | 2025 — within 3 year(s) of the newest study here |
| 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 | 1 / 7 | Cited 2 times (OpenAlex, 2026-10-10) |
| Citations per year | 0 / 5 | 0.7 citations a year over 3 year(s) since 2025 |
| Impact for its field and year | 2 / 6 | Cited 1.1× 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 | 0 / 4 | Cited 2 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | — / 4 | OpenAlex's profile for last-listed author Jiyu Ji holds only 4 work(s), too few to judge a track record — left out of this score |
| Institution's track record | 1 / 3 | University of Bristol: institution h-index 1,260 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 41346435) |
| Free to read | 2 / 2 | Free to read |
| 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
- DOI: 10.3389/fnagi.2025.1630826
- PubMed: 41346435
- Original source →
- Free full text: Frontiers in Aging Neuroscience →
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. The record names 7 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Zhou, S., Liu, M., Kuai, J., Yi, T., Zheng, Y., Bao, X., et al. (2025). Dysfunctional default mode and visual networks underlie cognitive deficits in dementia with Lewy bodies: a resting-state fMRI study. Frontiers in Aging Neuroscience. https://doi.org/10.3389/fnagi.2025.1630826
Vancouver
Zhou S, Liu M, Kuai J, Yi T, Zheng Y, Bao X, et al. Dysfunctional default mode and visual networks underlie cognitive deficits in dementia with Lewy bodies: a resting-state fMRI study. Frontiers in Aging Neuroscience. 2025. doi:10.3389/fnagi.2025.1630826. PMID: 41346435.
BibTeX
@article{zhou2025-41346435,
author = {Zhou, Su and Liu, Mengran and Kuai, Jun and Yi, Tingting and Zheng, Yuechang and Bao, Xinran and Ji, Jiyu},
title = {{Dysfunctional default mode and visual networks underlie cognitive deficits in dementia with Lewy bodies: a resting-state fMRI study}},
journal = {Frontiers in Aging Neuroscience},
year = {2025},
doi = {10.3389/fnagi.2025.1630826},
pmid = {41346435},
url = {https://doi.org/10.3389/fnagi.2025.1630826}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.