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Differential neurocognitive network perturbation in amnestic and aphasic Alzheimer disease
Martersteck A, Sridhar J, Rader B, Coventry C, Parrish T, Mesulam MM, Rogalski E.. Neurology, 2020-01-22
Topic: Amyloid, tau and blood-test diagnosis
Objective To determine if Alzheimer disease (AD) is associated with aphasic rather than amnestic dementias in certain circumstances related in part to perturbations in different networks. Methods Three groups were investigated: 14 participants suspected of having the neuropathology of AD based on clinically diagnosed amnestic dementia of the Alzheimer type (DAT), 26 individuals with primary progressive aphasia (PPA) with either a positive 18 F-florbetapir amyloid PET scan or confirmed AD at autopsy, and 26 neurologically intact controls. The groups were compared using rs-fMRI. Seeds included the left hemisphere inferior frontal gyrus (IFG) for the language network, the left hippocampus for the episodic memory network, and the left posterior cingulate for the default mode network (DMN). Results Greater connectivity perturbations were found from the hippocampus for the DAT group and from the IFG for the PPA group. Furthermore, connectivity alterations in the PPA group were more asymmetric and favored the language-dominant left hemisphere. Loss of connectivity from the DMN seed was of a similar magnitude in the PPA and DAT groups. Conclusions Despite the presumptive common underlying neuropathology of amyloid plaques and neurofibrillary tangles, the 2 groups displayed 2 different patterns of network perturbation, each concordant with the clinical presentation and the anatomy of neurodegeneration.
Key findings
- Objective To determine if Alzheimer disease (AD) is associated with aphasic rather than amnestic dementias in certain circumstances related in part to perturbations in different networks.
- Results Greater connectivity perturbations were found from the hippocampus for the DAT group and from the IFG for the PPA group.
Why it matters
This small imaging study found that people with amnestic versus aphasic presentations of Alzheimer's disease showed different patterns of brain network disruption despite presumed shared amyloid and tau pathology. It helps explain how the same pathology can produce different symptoms but does not test treatment, cure, or prevention.
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Study details
- Participants14
- Evidence strengthLow
How this study scored 44/100
Published in a leading specialty journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Neurology) |
| Journal's citation record | 4 / 4 | Neurology: journal h-index 525 (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 | 2 / 5 | 2020 — within 10 year(s) of the newest study here |
| Sample size | 1 / 4 | 14 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 2 / 7 | Cited 14 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 1.8 citations a year over 8 year(s) since 2020 |
| 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 | 1 / 6 | Cited by 1 other studies in this library |
| Still being cited | 1 / 4 | Cited 7 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Emily Joy Rogalski: h-index 59 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Northwestern University: institution h-index 1,592 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 31969462) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 44 / 100 | — |
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Read the original
- DOI: 10.1212/wnl.0000000000008960
- PubMed: 31969462
- Original source →
- Free full text: PubMed Central →
Full text: free to read — PubMed Central lists this copy as free to read: the link above (checked 10 Oct 2026).
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
Martersteck, A., Sridhar, J., Rader, B., Coventry, C., Parrish, T., Mesulam, M. M., et al. (2020). Differential neurocognitive network perturbation in amnestic and aphasic Alzheimer disease. Neurology. https://doi.org/10.1212/wnl.0000000000008960
Vancouver
Martersteck A, Sridhar J, Rader B, Coventry C, Parrish T, Mesulam MM, et al. Differential neurocognitive network perturbation in amnestic and aphasic Alzheimer disease. Neurology. 2020. doi:10.1212/wnl.0000000000008960. PMID: 31969462.
BibTeX
@article{martersteck2020-31969462,
author = {Martersteck, A. and Sridhar, J. and Rader, B. and Coventry, C. and Parrish, T. and Mesulam, M. M. and Rogalski, E.},
title = {{Differential neurocognitive network perturbation in amnestic and aphasic Alzheimer disease}},
journal = {Neurology},
year = {2020},
doi = {10.1212/wnl.0000000000008960},
pmid = {31969462},
url = {https://doi.org/10.1212/wnl.0000000000008960}
}
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