CENTRAL CONTROL OF SPEECH AND VOICE PRODUCTION AND PERCEPTION

几项研究正在使用经颅磁刺激进行 检查a)是否有双侧喉代表 B)如果对右侧或右侧刺激的反应 左侧皮质的波幅和潜伏期相等；c)如果喉部 肌肉反应的变化取决于激活任务是否 呼吸、言语或努力结束。在之前的一项研究中，刺激对 左侧产生了更大的幅度和更短的反应潜伏期 在喉部两侧与右侧刺激相比较。 第二项研究确定了对侧肌肉反应的阈值 到左侧和右侧的皮质刺激。没有重大意义 双侧阈值有差异的有4例 受试者的喉部或手部肌肉。当刺激物 以高于10%的阈值水平呈现，两种类型的响应 发生：刺激后10毫秒内发生的事件和 在10到20毫秒之间。早期的反应被发现在 同侧的波幅和潜伏期缩短。 第四项研究的目的是确定刺激是否 从头骨出来的外周神经， 产生与早期同侧反应类似的反应。当 同样的正常志愿者在外周和大脑皮层都受到刺激， 周围神经反应与早期皮质反应相似 只有1-2毫秒的延迟，表明早期的同侧反应 在经颅磁刺激期间最有可能是由于直接 刺激周围神经。 我们计划使用这项技术来检查与正常情况下的差异 声带运动患者的喉中央神经控制 精神错乱。

Several studies are being conducted using transcranial magnetic stimulation to examine if a) there is bilateral representation of the laryngeal musculature in each cortex; b) if responses to stimulation on the right or left cortices are equivalent in amplitude and latency; and c) if laryngeal muscle responses are changed depending upon whether the activation task is respiration, speech or effort closure. In a previous study, stimulation on the left side produced increased amplitudes and reduced response latencies on both sides of the larynx in comparison with stimulation on the right. A second study determined the thresholds for contralateral muscle responses to cortical stimulation on the left and right sides. No significant differences were found between the threshold values on the two sides in 4 subjects for either the laryngeal or hand muscles. When stimuli were presented at threshold levels of 10% greater, two types of responses occurred: those that were within 10 ms after stimulation and those that were between 10 and 20 ms. The early responses were found to be greater in amplitude and reduced in latency on the ipsilateral side. A fourth study was conducted aimed at determining whether stimulation of the nerve at the periphery at the point where it emerges from the skull, produced responses similar to the early ipsilateral responses. When the same normal volunteers were stimulated both peripherally and at the cortex, the peripheral nerve responses were similar to the early cortical responses with only a 1-2 Ms delay, indicating that early ipsilateral responses seen during transcranial magnetic stimulation are most likely due to direct stimulation of the peripheral nerve. We plan to use this technique to examine for differences from normal in central laryngeal neural control in patients with vocal fold movement disorders.