McEvoy L, Hari R, Imada T, Sams M
Low Temperature Laboratory, Helsinki University of Technology, Espoo, Finland.
Hear Res. 1993 May;67(1-2):98-109. doi: 10.1016/0378-5955(93)90237-u.
Neuromagnetic responses were recorded over the right temporal cortex using a 24-channel gradiometer. Stimuli were binaural click trains, presented with six separate interaural time differences (ITDs). N100m to sound onset was larger and earlier for stimuli presented with left- than with right-leading ITDs. With stimulus lateralization taken into account, monaural and binaural stimuli evoked responses of roughly equal amplitude. In selective adaptation and oddball experiments, stimuli presented with different ITDs excited overlapping neuronal populations, but the amount of overlap decreased as the ITD between the stimuli increased. There were no systematic differences in the cortical source locations of the N100m as a function of ITD, however. Thus it appears that ITD-sensitive neurons in the human auditory cortex are not organized into a large-scale, orderly representation, which could be resolved by MEG.
使用24通道梯度仪记录右侧颞叶皮质的神经磁反应。刺激为双耳点击序列，呈现六种不同的耳间时间差（ITD）。对于左侧领先ITD呈现的刺激，声音开始时的N100m比右侧领先ITD呈现的刺激更大且更早。考虑到刺激的侧化，单耳和双耳刺激诱发的反应幅度大致相等。在选择性适应和奇偶数实验中，不同ITD呈现的刺激激发重叠的神经元群体，但随着刺激之间的ITD增加，重叠量减少。然而，N100m的皮质源位置作为ITD的函数没有系统差异。因此，似乎人类听觉皮质中对ITD敏感的神经元没有组织成可通过MEG分辨的大规模有序表征。
