Residual spectrum: Brain functional connectivity detection beyond coherence

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Goto, Yuichi, Zhang, Xuze, Kedem, Benjamin, Chen, Shuo
Natura: Preprint
Pubblicazione: 2023
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866911879952072704
author Goto, Yuichi
Zhang, Xuze
Kedem, Benjamin
Chen, Shuo
author_facet Goto, Yuichi
Zhang, Xuze
Kedem, Benjamin
Chen, Shuo
contents Coherence is a widely used measure to assess linear relationships between time series. However, it fails to capture nonlinear dependencies. To overcome this limitation, this paper introduces the notion of residual spectral density as a higher-order extension of the squared coherence. The method is based on an orthogonal decomposition of time series regression models. We propose a test for the existence of the residual spectrum and derive its fundamental properties. A numerical study illustrates finite sample performance of the proposed method. An application of the method shows that the residual spectrum can effectively detect brain connectivity. Our study reveals a noteworthy contrast in connectivity patterns between schizophrenia patients and healthy individuals. Specifically, we observed that non-linear connectivity in schizophrenia patients surpasses that of healthy individuals, which stands in stark contrast to the established understanding that linear connectivity tends to be higher in healthy individuals. This finding sheds new light on the intricate dynamics of brain connectivity in schizophrenia.
format Preprint
id arxiv_https___arxiv_org_abs_2305_19461
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Residual spectrum: Brain functional connectivity detection beyond coherence
Goto, Yuichi
Zhang, Xuze
Kedem, Benjamin
Chen, Shuo
Statistics Theory
Methodology
62M15, 62M10, 62G10
Coherence is a widely used measure to assess linear relationships between time series. However, it fails to capture nonlinear dependencies. To overcome this limitation, this paper introduces the notion of residual spectral density as a higher-order extension of the squared coherence. The method is based on an orthogonal decomposition of time series regression models. We propose a test for the existence of the residual spectrum and derive its fundamental properties. A numerical study illustrates finite sample performance of the proposed method. An application of the method shows that the residual spectrum can effectively detect brain connectivity. Our study reveals a noteworthy contrast in connectivity patterns between schizophrenia patients and healthy individuals. Specifically, we observed that non-linear connectivity in schizophrenia patients surpasses that of healthy individuals, which stands in stark contrast to the established understanding that linear connectivity tends to be higher in healthy individuals. This finding sheds new light on the intricate dynamics of brain connectivity in schizophrenia.
title Residual spectrum: Brain functional connectivity detection beyond coherence
topic Statistics Theory
Methodology
62M15, 62M10, 62G10
url https://arxiv.org/abs/2305.19461