Direct electrophysiological mapping of human pitch-related processing in auditory cortex
Direct electrophysiological mapping of human pitch-related processing in auditory cortex
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DOI：
10.1016/j.neuroimage.2019.116076
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发表时间：
2019-11-15
期刊：
影响因子：
5.7
通讯作者：
Griffiths, Timothy D.
中科院分区：
文献类型：
--
作者：
Gander, Phillip E.;Kumar, Sukhbinder;Griffiths, Timothy D.
这项工作旨在寻找在听觉皮层神经元集群中由高于音高下限（LLP）的神经活动所定义的音高感知的相关因素，并研究它们的地形分布。在8名因药物难治性癫痫接受侵入性记录的患者中记录了局部场电位（LFPs）。刺激包括宽带噪声脉冲串，随后是定期间隔噪声（RIN）。RIN以低于和高于LLP的速率呈现，以区分与刺激规律性和音高本身存在相关的反应。使用植入在赫氏回（HG）和颞平面（PT）的多触点深度电极以及植入在颞上回外侧（STG）的硬膜下栅格电极，从人类听觉核心、带和旁带区域的皮质同源区记录LFPs。使用诱发反应的自相关评估与刺激时间规律性相对应的诱发反应，这些反应在低于和高于LLP的刺激中均出现。对于高于LLP的音高值，在整个高伽马范围（60 - 200 Hz）内存在诱导反应，起始潜伏期约为70毫秒。将诱导反应映射到共同的大脑空间表明，高伽马反应在不同受试者中的地形分布存在差异。诱导反应在HG的整个长度以及PT上均存在，这与先前的功能性神经影像学研究一致。此外，在每个受试者中，颞上回外侧的一个区域在诱发音高的刺激速率下显示出强烈的诱导反应。这项工作表明，在人类听觉核心和非核心皮质同源区的神经元集群中，音高处理是分布式表征的。
This work sought correlates of pitch perception, defined by neural activity above the lower limit of pitch (LLP), in auditory cortical neural ensembles, and examined their topographical distribution. Local field potentials (LFPs) were recorded in eight patients undergoing invasive recordings for pharmaco-resistant epilepsy. Stimuli consisted of bursts of broadband noise followed by regular interval noise (RIN). RIN was presented at rates below and above the LLP to distinguish responses related to the regularity of the stimulus and the presence of pitch itself. LFPs were recorded from human cortical homologues of auditory core, belt, and parabelt regions using multicontact depth electrodes implanted in Heschl's gyrus (HG) and Planum Temporale (PT), and subdural grid electrodes implanted over lateral superior temporal gyrus (STG). Evoked responses corresponding to the temporal regularity of the stimulus were assessed using autocorrelation of the evoked responses, and occurred for stimuli below and above the LLP. Induced responses throughout the high gamma range (60-200 Hz) were present for pitch values above the LLP, with onset latencies of approximately 70 ms. Mapping of the induced responses onto a common brain space demonstrated variability in the topographical distribution of high gamma responses across subjects. Induced responses were present throughout the length of HG and on PT, which is consistent with previous functional neuroimaging studies. Moreover, in each subject, a region within lateral STG showed robust induced responses at pitch-evoking stimulus rates. This work suggests a distributed representation of pitch processing in neural ensembles in human homologues of core and non-core auditory cortex.