title: Temporospatial identification of language-related cortical function by a combination of transcranial magnetic stimulation and magnetoencephalography.
abstract: BACKGROUND
  Identification of language-related cortical functions can be carried out noninvasively by transcranial magnetic stimulation (TMS) and magnetoencephalography (MEG), which allow for lesion-based interrogation and global temporospatial investigation of cortices, respectively. Combining these two modalities can improve the accuracy of the identification, but the relationships between them remain unclear. We compared TMS and MEG responses during the same language task to elucidate their temporospatial relationships and used the results to develop a novel method to identify language-related cortical functions.
  
  
  METHODS
  Twelve healthy right-handed volunteers performed a picture-naming task during TMS and MEG. TMS was applied on the right or left inferior frontal gyrus (IFG) at five time points, and the reaction times (RTs) for naming the pictures were measured. The temporospatial oscillatory changes measured by MEG during the same task were then compared with the TMS results.
  
  
  RESULTS
  Transcranial magnetic stimulation of the left IFG significantly lengthened RTs at 300 and 375 msec after picture presentation, whereas TMS of the right IFG did not change RTs significantly. Interestingly, the stimulus time point at which RTs increased significantly for each individual was correlated with when the low gamma event-related desynchronizations (ERDs) peaked in the left IFG. Moreover, combining the results of TMS and MEG improved the detection rate for identifying the laterality of language function.
  
  
  CONCLUSIONS
  These results suggest that the low gamma ERDs measured by MEG strongly relate to the language function of picture naming in the left IFG. Finally, we propose a novel method to identify language-related cortical functions by combining TMS and MEG.
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan.
authors: Misako
authors: M
authors: Shinshi
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan ; Department of Neurosurgery, Osaka University Graduate School of Medicine Suita, Japan.
authors: Takufumi
authors: T
authors: Yanagisawa
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan ; Department of Neurosurgery, Osaka University Graduate School of Medicine Suita, Japan.
authors: Masayuki
authors: M
authors: Hirata
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan ; Department of Neurosurgery, Osaka University Graduate School of Medicine Suita, Japan.
authors: Tetsu
authors: T
authors: Goto
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan ; Department of Neurosurgery, Osaka University Graduate School of Medicine Suita, Japan.
authors: Hisato
authors: H
authors: Sugata
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan.
authors: Toshihiko
authors: T
authors: Araki
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan.
authors: Yumiko
authors: Y
authors: Okamura
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan.
authors: Yuka
authors: Y
authors: Hasegawa
authors: Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, and Osaka University Kobe, Japan.
authors: Aya S
authors: AS
authors: Ihara
authors: Department of Functional Diagnostic Science, Osaka University Graduate School of Medicine Osaka, Japan.
authors: Shiro
authors: S
authors: Yorifuji
mesh_terms: D000328:Adult; D057186:Comparative Effectiveness Research; D005260:Female; D006801:Humans; D015225:Magnetoencephalography / Q000379:methods*; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D017397:Prefrontal Cortex / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D065855:Spatial Processing / Q000502:physiology; D013647:Task Performance and Analysis; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
keywords: Event-related desynchronizations; inferior frontal gyrus; language lateralization; language processing; low gamma; picture naming
references: IEEE Trans Biomed Eng. 2006 Sep;53(9):1755-64
references: 16941831
references: Neuroimage. 2013 Nov 15;82:260-72
references: 23702420
references: Prog Brain Res. 2006;159:275-95
references: 17071238
references: Clin Neurophysiol. 2007 Feb;118(2):237-54
references: 17008126
references: Epileptic Disord. 2007 Jun;9(2):111-26
references: 17525019
references: J Neurosurg. 2007 Jun;106(6):1117-33
references: 17564192
references: Behav Res Methods. 2007 Nov;39(4):1008-11
references: 18183919
references: J Neurosurg. 2008 Feb;108(2):411-21
references: 18240946
references: Cortex. 2009 Oct;45(9):1111-6
references: 19111289
references: Clin Neurophysiol. 2009 Dec;120(12):2008-39
references: 19833552
references: J Neurosurg. 2010 Mar;112(3):528-38
references: 19681682
references: Neuroimage. 2011 Jan 1;54(1):560-7
references: 20728551
references: Clin Neurophysiol. 1999 Nov;110(11):1842-57
references: 10576479
references: Curr Opin Neurobiol. 2000 Apr;10(2):232-7
references: 10753803
references: Psychophysiology. 2000 Jul;37(4):473-84
references: 10934906
references: Nat Rev Neurosci. 2000 Oct;1(1):73-9
references: 11252771
references: Science. 2003 Nov 14;302(5648):1181-5
references: 14615530
references: Radiology. 2004 Jan;230(1):49-54
references: 14695386
references: Neuroimage. 2004 Mar;21(3):1124-46
references: 15006680
references: Cognition. 2004 May-Jun;92(1-2):101-44
references: 15037128
references: Neuroimage. 2004 Sep;23(1):46-53
references: 15325351
references: Neuropsychologia. 1971 Mar;9(1):97-113
references: 5146491
references: Arch Neurol. 1986 Oct;43(10):1065-72
references: 3530216
references: Nature. 1988 Feb 18;331(6157):585-9
references: 3277066
references: Proc Natl Acad Sci U S A. 1993 Jun 1;90(11):4952-6
references: 8506340
references: Proc Natl Acad Sci U S A. 1993 Jun 1;90(11):4957-60
references: 8506341
references: J Neurosurg. 1993 Oct;79(4):584-8
references: 8410228
references: Nature. 1994 Mar 31;368(6470):463-5
references: 8133893
references: Brain. 1996 Feb;119 ( Pt 1):159-79
references: 8624678
references: Nature. 1996 Jun 6;381(6582):520-2
references: 8632824
references: J Cogn Neurosci. 1998 Sep;10(5):553-67
references: 9802989
references: J Neurosurg. 1999 Jan;90(1):85-93
references: 10413160
references: Philos Trans R Soc Lond B Biol Sci. 2005 Jun 29;360(1458):1185-205
references: 16147516
references: Neuron. 2006 Jun 15;50(6):963-74
references: 16772176
references: Comput Intell Neurosci. 2011;2011:852961
references: 21437221
references: Neuropsychologia. 2011 Apr;49(5):1350-4
references: 21251921
references: Science. 2013 Jun 14;340(6138):1230531
references: 23766329
references: Brain Res. 2006 Sep 27;1112(1):201-12
references: 16893534