Helen Wills Neuroscience Institute and Department of Psychology, University of California, Berkeley, California 94720, USA.
J Neurosci. 2010 Dec 8;30(49):16643-50. doi: 10.1523/JNEUROSCI.1809-10.2010.
The human auditory cortex is engaged in monitoring the speech of interlocutors as well as self-generated speech. During vocalization, auditory cortex activity is reported to be suppressed, an effect often attributed to the influence of an efference copy from motor cortex. Single-unit studies in non-human primates have demonstrated a rich dynamic range of single-trial auditory responses to self-speech consisting of suppressed, nonsuppressed and excited auditory neurons. However, human research using noninvasive methods has only reported suppression of averaged auditory cortex responses to self-generated speech. We addressed this discrepancy by recording electrocorticographic activity from neurosurgical subjects performing auditory repetition tasks. We observed that the degree of suppression varied across different regions of auditory cortex, revealing a variety of suppressed and nonsuppressed responses during vocalization. Importantly, single-trial high-gamma power (γ(High), 70-150 Hz) robustly tracked individual auditory events and exhibited stable responses across trials for suppressed and nonsuppressed regions.
人类听觉皮层参与监测对话者的言语以及自身产生的言语。在发声期间，据报道听觉皮层活动受到抑制，这种效应通常归因于来自运动皮层的传出副本的影响。在非人类灵长类动物中的单细胞研究表明，自我言语的单个试验听觉反应具有丰富的动态范围，包括抑制、非抑制和兴奋的听觉神经元。然而，使用非侵入性方法的人类研究仅报告了对自身产生的言语的平均听觉皮层反应的抑制。我们通过记录执行听觉重复任务的神经外科患者的脑电皮质电图活动来解决这一差异。我们观察到，在不同的听觉皮层区域，抑制的程度有所不同，在发声期间显示出各种抑制和非抑制的反应。重要的是，单个试验高伽马功率（γ（High），70-150 Hz）能够可靠地跟踪单个听觉事件，并在抑制和非抑制区域的试验中表现出稳定的反应。
