暗算と語想起による注意分散が視覚誘発脳磁界に及ぼす影響 The effects of divided attention on visual evoked magnetic fields during mental arithmetic tasks and a verbal fluency task

この論文にアクセスする

この論文をさがす

著者

    • 池田 拓郎 Ikeda Takuro
    • 国際医療福祉大学福岡保健医療学部理学療法学科 Department of Physical Therapy, Faculty of Health Sciences at Fukuoka, International University of Health and Welfare
    • 後藤 和彦 Goto Kazuhiko
    • 博多メディカル専門学校臨床工学技士科 Department of Clinical Engineering, Hakata Medical Technical College
    • 後藤 純信 Goto Yoshinobu
    • 国際医療福祉大学福岡保健医療学部作業療法学科 Department of Occupational Therapy, Faculty of Health Sciences at Fukuoka, International University of Health and Welfare

抄録

<p>内因性の注意分散が視覚誘発脳磁界 (VEFs) に及ぼす影響を検討した。対象は右利き健常成人14名。被検者に中央の固視点を注視させた状態で左右の半側視野に白–黒格子縞反転刺激を刺激頻度1 Hzで提示し, 暗算 (連続7減算および九九) と語想起を負荷した時のVEFsを全頭型306チャンネル脳磁計で記録した。その結果, 左半側視野刺激時に右後頭部のN75mの振幅が内因性思考課題によって低下し, また, 右後頭部のP100mの潜時が九九によって延長した。さらに, 左半側視野刺激時の高周波γ帯域律動反応 (50∼100 Hz) の頭皮上での広がりが課題遂行時に右前頭部で縮小し, 右後頭部での分布の広がりが九九によって拡大した。よって, 内因性の注意分散が視覚情報処理機能の初期段階での神経細胞の活動を抑制させると考えられた。さらに, 高周波γ帯域律動反応の分布の広がりが異なる情報処理を同時に遂行するための皮質間の機能的分散や統合の指標となると推察された。</p>

<p>[Objective] The aim of this study was to investigate the specific spatiotemporal brain processes of divided attention in mental arithmetic and verbal fluency tasks using visual evoked magnetic fields (VEFs). <br>[Methods] VEFs were recorded using a 306-channel MEG in 14 healthy adult right-handed volunteers. To evoke visual responses, a hemifield black–white checkerboard pattern was phase-reversed at a rate of 1 Hz to stimulate either the right or left visual hemifield. The subjects were instructed to fixate on a red dot placed 0.2º of arc laterally from the stimulated hemifield. VEFs were recorded with or without endogenous tasks, which included mental arithmetic tasks (serial subtraction and multiplication facts) and a verbal fluency task. The amplitudes and latencies of VEF components (the N75m, P100m and N145m) were measured. Additionally, VEFs were analyzed using fast Fourier transformation (FFT), and the topographic distribution of gamma band activity was then plotted. <br>[Results] The amplitude change in N75m on the left hemifield stimulation was significantly decreased in all endogenous tasks compared to the control condition (normal task). The latency change of the P100m on the left hemifield stimulation was significantly longer in the multiplication facts task than in the control condition and the successive subtraction task. In addition, the distribution of high-gamma band activity in the left hemifield was contracted to the right frontal area during both types of dispersion tasks. Furthermore, the power value of the right occipital area was expanded in both the occipital lobe and parietal lobe during the multiplication facts task. <br>[Conclusions] Our results suggest that the VEF changes are the evidence of the inhibition of visual information processing in the primary visual cortex that occurs during endogenous tasks. In addition, the high gamma band activity changes maybe evidence of the neural connection or inhibition of information processing in cortico-cortical communication.</p>

収録刊行物

  • 臨床神経生理学

    臨床神経生理学 45(3), 137-145, 2017

    一般社団法人 日本臨床神経生理学会

各種コード

  • NII論文ID(NAID)
    130006398077
  • NII書誌ID(NCID)
    AA11410258
  • 本文言語コード
    JPN
  • ISSN
    1345-7101
  • NDL 記事登録ID
    028314436
  • NDL 請求記号
    Z19-1109
  • データ提供元
    NDL  J-STAGE 
ページトップへ