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EEG coherence in Alzheimer's disease
Locatelli T, Cursi M, Liberati D, Franceschi M, Comi G.. Electroencephalography and clinical neurophysiology, 1998-03-01
Topic: Brain imaging, connectivity and assessment
EEG coherence can be used to evaluate the functionality of cortical connections and to get information about the synchronization of the regional cortical activity. We studied EEG coherence in patients affected by clinically probable Alzheimer's disease (AD) in order to quantify the modifications in the cortico-cortical or cortico-subcortical connections. The EEGs were recorded in 10 AD patients (with mild or moderate degrees of dementia) and in 10 normal age-matched subjects, at rest and eye-closed, from 16 electrodes with linked-ears reference. Spectral parameters and coherence were calculated by a multichannel autoregressive model using 50 artifact-free epochs, 1 s duration each. Alpha coherence was significantly decreased in 6 patients, the decrease being more accentuated in the area near the electrode taken into account; a significant delta coherence increase was found in a few patients between frontal and posterior regions. The AD group showed a significant decrease of alpha band coherence, in particular in temporo-parieto-occipital areas, more evident in patients with a more severe cognitive impairment. These abnormalities could reflect two different pathophysiological changes: the alpha coherence decrease could be related to alterations in cortico-cortical connections, whereas the delta coherence increase could be related to the lack of influence of subcortical cholinergic structures on cortical electrical activity.
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APA 7th
Locatelli, T., Cursi, M., Liberati, D., Franceschi, M., & Comi, G. (1998). EEG coherence in Alzheimer's disease. Electroencephalography and clinical neurophysiology. https://doi.org/10.1016/s0013-4694(97)00129-6
Vancouver
Locatelli T, Cursi M, Liberati D, Franceschi M, Comi G. EEG coherence in Alzheimer's disease. Electroencephalography and clinical neurophysiology. 1998. doi:10.1016/s0013-4694(97)00129-6. PMID: 9743281.
BibTeX
@article{locatelli1998-9743281,
author = {Locatelli, T. and Cursi, M. and Liberati, D. and Franceschi, M. and Comi, G.},
title = {{EEG coherence in Alzheimer's disease}},
journal = {Electroencephalography and clinical neurophysiology},
year = {1998},
doi = {10.1016/s0013-4694(97)00129-6},
pmid = {9743281},
url = {https://doi.org/10.1016/s0013-4694(97)00129-6}
}
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Key findings
- Alpha coherence was significantly decreased in 6 patients, the decrease being more accentuated in the area near the electrode taken into account; a significant delta coherence increase was found in a few patients between frontal and posterior regions.
- The AD group showed a significant decrease of alpha band coherence, in particular in temporo-parieto-occipital areas, more evident in patients with a more severe cognitive impairment.
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Study details
- Evidence strengthLow
How this study scored 36/100
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 journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 21 of the 58 points we could judge it on, which is 36 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Electroencephalography and clinical neurophysiology) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| 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 | 1 / 5 | 1998 — 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 | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9743281) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 21 / 58 | Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 21 of the 58 points we could judge it on is 36 out of 100. |
| Total | 36 / 100 | — |
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