オザキ　イサム   Ozaki Isamu   尾﨑　勇    所属   東邦大学  医学部 医学科    職種   研究員（寄付講座）
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Impulse Propagation along Thalamocortical Fibers Can Be Detected Magnetically outside the Human Brain
掲載誌名	正式名：JOURNAL OF NEUROSCIENCE ISSNコード：0270-6474
出版社	SOC NEUROSCIENCE
巻・号・頁	28(47),pp.12535-12538
著者・共著者	Tomoaki Kimura,Isamu Ozaki,Isao Hashimoto
発行年月	2008/11
概要	Orchestrating cortical network activity with synchronous oscillations of neurons across distant regions of the brain underlies information processing in humans (Knight, 2007) and monkeys (Saalmann et al., 2007; Womelsdorf et al., 2007). Frequencies of oscillatory activities depend, to a considerable extent, on the length and conduction velocity of the tracts connecting the neural areas that participate in oscillations (Buzsaki, 2006). However, the impulse propagation along the fiber tracts in the white matter has never been visualized in humans. Here, we show, by recording magnetoencephalogram (MEG) following median nerve stimulation, that a magnetic field component, we labeled " M15," changes dynamically within 1.6-1.8 ms before the onset of magnetic M20 response generated from the primary somatosensory cortex. This new M15 component corresponds to the intracellular depolarizing action current in the thalamocortical fibers propagating with the mean conduction velocity of 29 m/s. The findings challenge the traditional view that MEG is blind to the activity of deep subcortical structures. We argue that the MEG technique holds the promise of providing novel information in impulse transmissions along not only the thalamocortical pathway but also other fiber tracts connecting distant brain areas in humans.
DOI	10.1523/JNEUROSCI.3022-08.2008
PMID	19020045