Dept of Psychology, UCL. Gower Street, London WC1E 6BT.
Institute of Cognitive Neuroscience, UCL, 17 Queen Square London WC1N 3AR.
J Speech Lang Hear Res. 2010 Apr;53(2):226-236. doi: 10.1044/1092-4388(2009/09-0009). Epub 2009 Nov 30.
Delayed auditory feedback is a technique that can improve fluency in stutterers, while disrupting fluency in many nonstuttering individuals. The aim of this study was to determine the neural basis for the detection of and compensation for such a delay, and the effects of increases in the delay duration.
Positron emission tomography was used to image regional cerebral blood flow changes, an index of neural activity, and to assess the influence of increasing amounts of delay.
Delayed auditory feedback led to increased activation in the bilateral superior temporal lobes, extending into posterior-medial auditory areas. Similar peaks in the temporal lobe were sensitive to increases in the amount of delay. A single peak in the temporal parietal junction responded to the amount of delay but not to the presence of a delay (relative to no delay).
This study permitted distinctions to be made between the neural response to hearing one's voice at a delay and the neural activity that correlates with this delay. Notably, all the peaks showed some influence of the amount of delay. This result confirms a role for the posterior, sensorimotor "how" system in the production of speech under conditions of delayed auditory feedback.
延迟听觉反馈是一种可以提高口吃者流畅度的技术，同时也会打乱许多非口吃者的流畅度。本研究旨在确定检测和补偿这种延迟的神经基础，以及延迟持续时间增加的影响。
正电子发射断层扫描（PET）用于成像区域脑血流变化，这是神经活动的一个指标，并评估了增加延迟量的影响。
延迟听觉反馈导致双侧颞上回的激活增加，延伸到后内侧听觉区域。颞叶中的类似峰值对延迟量的增加很敏感。颞顶交界处的单个峰值对延迟量有反应，但对是否存在延迟（相对于没有延迟）没有反应。
这项研究使得能够区分听到自己的声音延迟时的神经反应和与这种延迟相关的神经活动。值得注意的是，所有的峰值都显示出对延迟量的某种影响。这一结果证实了后、感觉运动“如何”系统在延迟听觉反馈条件下产生言语的作用。
