Spontaneous Slow Fluctuation of EEG Alpha Rhythm Reflects Activity in Deep-Brain Structures: A Simultaneous EEG-fMRI Study

Kei Omata; Takashi Hanakawa; Masako Morimoto; Manabu Honda

doi:10.1371/journal.pone.0066869

Spontaneous Slow Fluctuation of EEG Alpha Rhythm Reflects Activity in Deep-Brain Structures: A Simultaneous EEG-fMRI Study

PLoS One. 2013 Jun 18;8(6):e66869. doi: 10.1371/journal.pone.0066869. Print 2013.

Authors

Kei Omata¹, Takashi Hanakawa, Masako Morimoto, Manabu Honda

Affiliation

¹ Department of Functional Brain Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Tokyo, Japan ; Department of Biofunctional Imaging, Medical Photonics Research Center, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan ; Japan Science and Technology Agency, CREST, Saitama, Japan.

Abstract

The emergence of the occipital alpha rhythm on brain electroencephalogram (EEG) is associated with brain activity in the cerebral neocortex and deep brain structures. To further understand the mechanisms of alpha rhythm power fluctuation, we performed simultaneous EEGs and functional magnetic resonance imaging recordings in human subjects during a resting state and explored the dynamic relationship between alpha power fluctuation and blood oxygenation level-dependent (BOLD) signals of the brain. Based on the frequency characteristics of the alpha power time series (APTS) during 20-minute EEG recordings, we divided the APTS into two components: fast fluctuation (0.04-0.167 Hz) and slow fluctuation (0-0.04 Hz). Analysis of the correlation between the MRI signal and each component revealed that the slow fluctuation component of alpha power was positively correlated with BOLD signal changes in the brain stem and the medial part of the thalamus and anterior cingulate cortex, while the fast fluctuation component was correlated with the lateral part of the thalamus and the anterior cingulate cortex, but not the brain stem. In summary, these data suggest that different subcortical structures contribute to slow and fast modulations of alpha spectra on brain EEG.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Alpha Rhythm*
Brain / diagnostic imaging
Brain / physiology*
Electroencephalography / methods*
Female
Humans
Magnetic Resonance Imaging / methods*
Male

Grants and funding

This work was partly supported by Japan Science and Technology Agency, CREST (URL: http://www.jst.go.jp/kisoken/crest/en/research_area/ongoing/area02-1.html), a Grant-in-Aid for Scientific Research on Innovative Areas (Brain and Information Science on SHITSUKAN)(URL: http://shitsukan.jp/content/137, Number: C01-3) and a Health Labour Sciences Research Grant (URL: http://www.mhlw.go.jp/bunya/kenkyuujigyou/hojokin-koubo20/07-03.html, Number: 33) to M.H. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.