---
title: "Specification dependence of EEG theta/alpha ratio associations with cognitive impairment: multiver"
id: "biorxiv-21-specification-dependence-of-eeg-theta-alpha-ratio-associations-with-cognitive"
canonical_url: "https://medichelpline.com/clinical-feed/biorxiv-21-specification-dependence-of-eeg-theta-alpha-ratio-associations-with-cognitive"
content_type: "clinical_feed_article"
specialty: "Neurology"
source_name: "bioRxiv (Biomedical Preprints)"
source_url: "https://www.biorxiv.org/content/10.64898/2026.09.03.749187v1?rss=1"
published_at: "2026-09-08T12:00:00.000Z"
evidence_level: "Verified Feed"
license: "CC-BY-NC-4.0 / Informational Use"
---
# Specification dependence of EEG theta/alpha ratio associations with cognitive impairment: multiver
## Provenance & Clinical Metadata
- **Canonical URL:** https://medichelpline.com/clinical-feed/biorxiv-21-specification-dependence-of-eeg-theta-alpha-ratio-associations-with-cognitive
- **Specialty:** [Neurology](https://medichelpline.com/clinical-feed/neurology.md)
- **Primary Source:** bioRxiv (Biomedical Preprints)
- **Source URL:** [Original Journal Publication](https://www.biorxiv.org/content/10.64898/2026.09.03.749187v1?rss=1)
- **Published At:** 2026-09-08T12:00:00.000Z
- **Evidence Rating:** Verified Feed
## Executive GIST (TL;DR)
- The study evaluated the robustness of the **EEG theta/alpha ratio** as a marker of **cognitive impairment** using a multiverse analysis that varied preprocessing, spectral, spatial, and statistical choices. - Two resting-state EEG datasets were analyzed: Dataset 1 (49 controls; 100 people with Parkinson's disease across cognitive status from normal to dementia) and Dataset 2 (29 controls; 36 with Alzheimer's disease; 23 with frontotemporal dementia). - Eight analytic decisions were varied across the pipelines: filtering, artifact correction, independent component analysis (**ICA**), referencing, spatial summary, alpha-band definition, spectral method, and covariate adjustment, producing 1,280 distinct specifications (universes). - Results were specification-dependent but showed consistent directionality: higher **theta/alpha ratios** associated with greater cognitive impairment across many specifications. - In Dataset 1, universes within an exploratory family that combined **ICA** with absolute **FFT** or **Welch** power yielded p < 0.05 for comparisons of controls and cognitively normal Parkinson's disease versus Parkinson's disease dementia, and produced significant associations with **Montreal Cognitive Assessment** scores in over 95% of universes. - In Dataset 2, absolute **FFT** or **Welch** power supported control versus Alzheimer's disease group differences in more than 95% of universes, while **ICA** with absolute power produced significant **Mini-Mental State Examination (MMSE)** associations in all specifications. - The authors conclude the **theta/alpha ratio** is a promising marker but its observed associations are contingent particularly on **ICA** and the method for spectral power quantification (absolute FFT or Welch). - The work emphasizes identifying analytic conditions that yield stable findings to support standardized, reproducible evaluation of quantitative **EEG** markers of cognitive impairment. - The authors declared no competing interests in the preprint.
## Clinical Analysis & Structured Key Points
Specification dependence of EEG theta/alpha ratio associations with cognitive impairment: a multiverse analysis | bioRxiv Skip to main content New Results Specification dependence of EEG theta/alpha ratio associations with cognitive impairment: a multiverse analysis Jinwon Chang , Seo Ho Song doi: https://doi.org/10.64898/2026.09.03.749187 Jinwon Chang 1 Williams College; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Seo Ho Song 2 Beth Israel Deaconess Medical Center Find this author on Google Scholar Find this author on PubMed Search for this author on this site For correspondence: ssong4{at}bidmc.harvard.edu Abstract Info/History Metrics Supplementary material Preview PDF Abstract Objective: The theta/alpha ratio, an index of electroencephalographic slowing, has been proposed as a marker of cognitive impairment, but estimates may depend on preprocessing, spectral, spatial, and statistical decisions. We used multiverse analysis to evaluate its robustness across plausible pipelines. Methods: Two resting-state EEG datasets were analyzed. Dataset 1 included 49 controls and 100 participants with Parkinson's disease spanning normal cognition to dementia. Dataset 2 included 29 controls, 36 patients with Alzheimer's disease, and 23 with frontotemporal dementia. Eight decisions were varied: filtering, artifact correction, independent component analysis (ICA), referencing, spatial summary, alpha-band definition, spectral method, and covariate adjustment, yielding 1,280 specifications (universes). Results: Findings varied across the unrestricted multiverse. In Dataset 1, all universes in the exploratory family combining ICA with absolute fast Fourier transform (FFT) or Welch power yielded p < 0.05 for comparisons of controls and cognitively normal Parkinson's disease with Parkinson's disease dementia and produced significant associations with Montreal Cognitive Assessment scores in more than 95% of universes. In Dataset 2, absolute FFT or Welch power supported control versus Alzheimer's disease differences in more than 95% of universes, while ICA with absolute power yielded significant Mini-Mental State Examination associations in all specifications. Higher theta/alpha ratios were consistently associated with greater cognitive impairment. Conclusions: The theta/alpha ratio is a promising but specification-dependent marker of cognitive impairment, contingent particularly on ICA and spectral power quantification. Significance: Identifying the analytic conditions under which theta/alpha findings remain stable supports standardized, reproducible evaluation of quantitative EEG markers of cognitive impairment. Competing Interest Statement The authors have declared no competing interest. Copyright The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY-NC-ND 4.0 International license . Back to top Previous Next Posted September 08, 2026. Download PDF Supplementary Material Email Thank you for your interest in spreading the word about bioRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. 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Share Specification dependence of EEG theta/alpha ratio associations with cognitive impairment: a multiverse analysis Jinwon Chang , Seo Ho Song bioRxiv 2026.09.03.749187; doi: https://doi.org/10.64898/2026.09.03.749187 Share This Article: Copy Citation Tools Specification dependence of EEG theta/alpha ratio associations with cognitive impairment: a multiverse analysis Jinwon Chang , Seo Ho Song bioRxiv 2026.09.03.749187; doi: https://doi.org/10.64898/2026.09.03.749187 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Areas All Articles Animal Behavior and Cognition (7974) Biochemistry (18640) Bioengineering (14772) Bioinformatics (44173) Biophysics (22474) Cancer Biology (19600) Cell Biology (26759) Clinical Trials (138) Developmental Biology (13904) Ecology (20894) Epidemiology (2067) Evolutionary Biology (25327) Genetics (16101) Genomics (23408) Immunology (18614) Microbiology (42253) Molecular Biology (17950) Neuroscience (92956) Paleontology (693) Pathology (2973) Pharmacology and Toxicology (5066) Physiology (8070) Plant Biology (15915) Scientific Communication and Education (2092) Synthetic Biology (4538) Systems Biology (10190) Zoology (2376)
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