Department of Speech, Language, and Hearing Sciences, Moody College of Communication, The University of Texas at Austin, Austin, Texas 78712.
Departments of Neurosurgery, Baylor College of Medicine, Houston, Texas 77030.
J Neurosci. 2024 Nov 20;44(47):e1109242024. doi: 10.1523/JNEUROSCI.1109-24.2024.
The human auditory cortex is organized according to the timing and spectral characteristics of speech sounds during speech perception. During listening, the posterior superior temporal gyrus is organized according to onset responses, which segment acoustic boundaries in speech, and sustained responses, which further process phonological content. When we speak, the auditory system is actively processing the sound of our own voice to detect and correct speech errors in real time. This manifests in neural recordings as suppression of auditory responses during speech production compared with perception, but whether this differentially affects the onset and sustained temporal profiles is not known. Here, we investigated this question using intracranial EEG recorded from seventeen pediatric, adolescent, and adult patients with medication-resistant epilepsy while they performed a reading/listening task. We identified onset and sustained responses to speech in the bilateral auditory cortex and observed a selective suppression of onset responses during speech production. We conclude that onset responses provide a temporal landmark during speech perception that is redundant with forward prediction during speech production and are therefore suppressed. Phonological feature tuning in these "onset suppression" electrodes remained stable between perception and production. Notably, auditory onset responses and phonological feature tuning were present in the posterior insula during both speech perception and production, suggesting an anatomically and functionally separate auditory processing zone that we believe to be involved in multisensory integration during speech perception and feedback control.
人类听觉皮层在感知言语时根据言语声音的时间和频谱特征进行组织。在聆听过程中，后上颞叶根据起始反应进行组织，起始反应可以分割言语中的声学边界，而持续反应则进一步处理语音内容。当我们说话时，听觉系统会主动处理自己声音的声音，以实时检测和纠正言语错误。这在神经记录中表现为与感知相比，在言语产生期间抑制听觉反应，但这种抑制是否会对起始和持续的时间分布产生不同的影响尚不清楚。在这里，我们使用来自 17 名患有抗药性癫痫的儿科、青少年和成年患者的颅内 EEG 研究了这个问题，他们在执行阅读/聆听任务时进行了研究。我们在双侧听觉皮层中识别了言语的起始和持续反应，并观察到在言语产生期间起始反应的选择性抑制。我们得出的结论是，起始反应在言语感知期间提供了一个时间标记，该标记在言语产生期间与前向预测冗余，因此被抑制。在这些“起始抑制”电极中，语音特征调谐在感知和产生之间保持稳定。值得注意的是，在听觉感知和产生过程中，听觉起始反应和语音特征调谐都存在于后岛叶，这表明存在一个解剖和功能上分离的听觉处理区域，我们认为该区域参与了言语感知和反馈控制过程中的多感觉整合。
