Pantev C
Clinical Research Unit, Biomagnetism and Biosignal Analysis, University of Münster, Germany.
Brain Topogr. 1995 Summer;7(4):321-30. doi: 10.1007/BF01195258.
The evoked gamma-band activity is an event related rhythmic response which persists within the first 100 ms after the stimulus onset. It shows spectral peaks between 30 and 40 Hz in the auditory, between 45 and 55 Hz in the somatosensory and between 100 and 110 Hz in the visual system. After separation of the wide-band activity in slow and gamma-band activity, a moving single equivalent current dipole model accounts for each activity almost completely. The induced gamma-band activity is not phase-locked to the stimulus or it is strongly gittering and thus it cannot be extracted in time domain. In this case we are using signal analysis methods in frequency domain. The evaluation of the induced brain gamma-band activity around 30 Hz shows differences to word and nonword stimuli. It was supposed that the induced gamma-band activity represents the synchronized activity of Hebbian cell assemblies correlated to words.
诱发伽马波段活动是一种与事件相关的节律性反应，在刺激开始后的前100毫秒内持续存在。它在听觉系统中显示出30至40赫兹之间的频谱峰值，在体感系统中为45至55赫兹之间，在视觉系统中为100至110赫兹之间。在将宽带活动分离为慢波和伽马波段活动后，一个移动的单等效电流偶极子模型几乎可以完全解释每种活动。诱发的伽马波段活动与刺激没有锁相，或者它强烈抖动，因此无法在时域中提取。在这种情况下，我们使用频域中的信号分析方法。对30赫兹左右诱发的脑伽马波段活动的评估显示，对单词和非单词刺激存在差异。据推测，诱发的伽马波段活动代表了与单词相关的赫布细胞集合的同步活动。
