Suchý Daniel, Behroozmand Roozbeh, Railo Henry
Department of Psychology and Speech-Language Pathology, University of Turku, Finland; Turku Brain and Mind Centre, University of Turku, Finland.
Speech Neuroscience Lab, Department of Speech Language and Hearing, Callier Center for Communication Disorders, School of Behavioral and Brain Sciences, The University of Texas at Dallas, 2811N. Floyd Rd, Richardson, TX 75080, United States.
Neuroimage. 2025 Jul 1;314:121269. doi: 10.1016/j.neuroimage.2025.121269. Epub 2025 May 13.
During vocalization, mismatches between expected and perceived auditory feedback are processed rapidly and automatically, suggesting that feedback control of vocalization operates unconsciously. However, whether consciousness modulates speech feedback control remains little studied. To address this question, we concurrently measured behavioral vocal responses and electroencephalography (EEG) in 30 participants while they vocalized and their auditory feedback was perturbed with individually calibrated perceptual threshold level pitch shifts. Following each vocalization trial, participants rated if they consciously detected a pitch shift in their auditory feedback. We analyzed the data on a trial-by-trial basis to test if vocal responses to pitch perturbations were modulated by conscious perception. Our results revealed that even on trials where the participants reported not noticing the pitch shift at all, a compensatory vocal response to the altered auditory feedback was generated. Conscious detection of a pitch shift was associated with an increased magnitude of vocal responses roughly 500-700 ms after the pitch shift compared to the unconscious trials. Conscious detection of the pitch shift correlated with early (Auditory awareness negativity, AAN) and late (Late positivity, LP) neural responses as indexed by the modulation of event-related potentials (ERPs). Source localization of the ERPs suggested that conscious pitch shift detection was associated with increased neural activity within the temporal, frontal and parietal cortical networks known to be involved in speech motor control. These findings emphasize the importance of investigating the role of consciousness in regulating speech feedback control, and their effect on the underlying neural and behavioral functions.
在发声过程中，预期听觉反馈与感知到的听觉反馈之间的不匹配会被快速且自动地处理，这表明发声的反馈控制是在无意识状态下进行的。然而，意识是否会调节言语反馈控制，目前仍鲜少有人研究。为了解决这个问题，我们让30名参与者在发声时同时测量其行为性发声反应和脑电图（EEG），并通过个体校准的感知阈值水平音高偏移来干扰他们的听觉反馈。在每次发声试验后，参与者对他们是否有意识地察觉到听觉反馈中的音高变化进行评分。我们逐次试验地分析数据，以测试对音高扰动的发声反应是否受到意识感知的调节。我们的结果显示，即使在参与者报告完全没有注意到音高变化的试验中，针对改变后的听觉反馈仍会产生补偿性发声反应。与无意识试验相比，在音高变化后约500 - 700毫秒，有意识地察觉到音高变化与发声反应幅度的增加有关。有意识地察觉到音高变化与早期（听觉意识负波，AAN）和晚期（晚期正波，LP）神经反应相关，这通过事件相关电位（ERP）的调制来衡量。ERP的源定位表明，有意识地检测到音高变化与颞叶、额叶和顶叶皮质网络内神经活动的增加有关，这些网络已知参与言语运动控制。这些发现强调了研究意识在调节言语反馈控制中的作用及其对潜在神经和行为功能的影响的重要性。
