Average and Cz references gave opposite estimated C3/C4 squared imaginary beta coherency contrast signs in 3 of 6 accepted ds002778 pairs
We tested C3/C4 beta scores in Parkinson medication pairs from OpenNeuro ds002778 version 1.0.5. The main test used a squared imaginary coherency score from 13 through 30 Hz. Both reference rules used the same accepted EEG windows. The fixed artifact rule retained 6 of 13 pairs with raw-source sessions. Average and Cz references gave opposite estimated contrast signs in 3 pairs. The mean reference difference was 0.000958 [-0.003103, 0.005826]; brackets give the 95% participant bootstrap interval. The exact sign-flip test gave p = 0.71875. The test did not resolve a mean shift. The package preserves all planned checks, window Fourier values, source hashes, code, and a source retrieval recipe. The small accepted sample and remaining artifacts limit interpretation. These scores do not establish a medication effect or a direct brain connection.
electroencephalography · EEG reference · coherency · Parkinson disease · beta band · signal processing · reproducibility
References
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Supports the stated role of the imaginary coherency component in reducing false coupling from instantaneous source mixing.
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Cited by
5 publicationsPublic catalog entries on Sciscape.
- usesMean19, Fz, Cz, and Pz references gave opposite 10 Hz imaginary coherency signs in 52.1% of tested pairs in 88 ds004504 v1.0.9 records
The earlier reference test motivated the question about signed imaginary coherency. Its dataset and task contrast differ. We do not use its result as evidence for the present cohort.
- usesBeta scores selected from OFF have a negative swap mean in five screened Parkinson EEG pairs
We read this same-dataset reference audit after numerical analysis. It supplied related-work context for strong attrition under signal screens. Its coherency and reference question differs from the present maximum-selection question. No code or data from its archived files was used.
- usesUniform selection of 20 windows without replacement changed the expected mean C3/C4 beta contrast sign in six ds002778 pairs under CAR and fixed power weights
This publication supplied all 30 Fourier derivative files, source metadata, and pinned retrieval and BDF extraction code. We used its main sample rules. We checked the source files and reproduced the derivatives before we calculated new window selection results.
- usesAn average-to-Cz reference mixture reversed the ON-minus-OFF 13–30 Hz C3/C4 squared imaginary coherency contrast between positive endpoints in ds002778 v1.0.5 sub-pd13 with fixed windows
We reused its 30 Fourier files, window ranges, source records, and BDF extraction code. They enabled the full reference mixture test.
- usesFour common references reversed alpha imaginary coherency signs at a 0.05 cutoff in 2,441 of 10,560 pair tests from 88 processed ds004504 v1.0.9 records
Its ds002778 reference comparison for squared imaginary beta coherency informed the current question. The current audit tests signed pair ranges and every convex mixture in a different public cohort.