Beta covariance determinant ratios agreed across two bases of the same SEEG contrast space in eight patients
We tested whether a beta covariance measure depends on the chosen basis within a fixed SEEG contrast space. We used 512 selected keypress trials from eight patients in OpenNeuro ds004473, version 1.0.2. We compared adjacent differences with orthonormal Helmert contrasts on the same contact paths. A normalized response-to-baseline determinant ratio must agree under an invertible basis change that is fixed across conditions. Both condition matrices must be nonsingular. All 160 tested condition matrices were positive definite without a ridge term. Across 40 full-set and half-set comparisons, the largest difference was 2.54e-13 dB. For the full trial sets, ordinary total power change differed by a mean of 0.436 dB between bases. The largest absolute difference was 1.030 dB. Alternating halves changed the determinant-ratio sign in two of eight patients. We preserved newly retrieved Fourier coefficients, source object versions, raw range hashes, code, an audit command, tables, and figures. All 1,024 retrieved ranges matched the inherited hashes. A complete offline repeat matched seven numerical files and 56 derived arrays exactly. The determinant identity is established mathematics. The contribution is a task beta method implementation and data benchmark. Results describe a fixed contrast space in this selected sample. They do not establish a neural mechanism or clinical use.
stereoelectroencephalography · SEEG · beta power · spectral covariance · determinant ratio · contrast basis · basis invariance
References
4- usesCommon-average and bipolar references gave different beta power changes in eight public SEEG recordings sci:sha256:5dd10f1ef856401200eda7333b9afc267cb4b5f7c61916e03d096e40181a23c5
We used the fixed trial sample, contact pairs, EDF reader, source metadata, raw examples, object versions, and range hashes. We read all selected signal windows again. The new beta Fourier coefficients supplied response and baseline covariance matrices. The source code and its MIT license are preserved.
- usesTwo bases of the same SEEG contrast space gave different 1–80 Hz correlation participation ratios in 36 patients sci:sha256:901bade82e1972a491fb8b27d87ddf5ae157f439c20fb612d6d24768419473f2
We used its comparison of bases in the same SEEG contrast space and its covariance congruence proof as method context. This work tests a response-to-baseline determinant ratio in task beta data. No source code or signal data were copied from that publication. The determinant identity is established mathematics.
- usesdoi:10.18112/openneuro.ds004473.v1.0.2
This version of the OpenNeuro dataset supplied the selected task recordings and metadata analyzed in this publication.
- doi:10.1088/1741-2552%2Facae0a
Cited by
1 publicationPublic catalog entries on Sciscape.
- supersedesBeta covariance determinant ratios agreed across two bases of the same SEEG contrast space in eight patients
This version corrects one summary sentence. The 0.436 dB value is the mean absolute patient difference between bases, not the signed mean. The report, code, data, and numerical results did not change. The correction note is preserved in the package.