Bullock Latané, Forseth Kiefer J, Woolnough Oscar, Rollo Patrick S, Tandon Nitin
Vivian L. Smith Department of Neurosurgery, McGovern Medical School at UT Health Houston, Houston, TX 77030, United States of America.
Texas Institute for Restorative Neurotechnologies, University of Texas Health Science Center at Houston, Houston, TX 77030, United States of America.
iScience. 2024 Dec 4;28(1):111531. doi: 10.1016/j.isci.2024.111531. eCollection 2025 Jan 17.
Speech production engages a distributed network of cortical and subcortical brain regions. The supplementary motor area (SMA) has long been thought to be a key hub in coordinating across these regions to initiate voluntary movements, including speech. We analyzed direct intracranial recordings from 115 patients with epilepsy as they articulated a single word in a subset of trials from a picture-naming task. We aimed to characterize the temporal dynamics of SMA relative to other cortical regions. SMA and preSMA were among the first regions to activate after cue onset, peaked in activity before articulation onset, and were the earliest regions to predict trial-to-trial response time. Neural activity at single electrodes in SMA and preSMA was closely associated with speech initiation; activity began at a highly predictable time after stimulus onset and extended until speech onset for any given trial. Our results support the idea that SMA is a key node in the speech initiation network.
言语产生涉及大脑皮层和皮层下区域的分布式网络。长期以来，辅助运动区（SMA）一直被认为是协调这些区域以启动包括言语在内的自主运动的关键枢纽。我们分析了115例癫痫患者在图片命名任务的一部分试验中说出单个单词时的直接颅内记录。我们旨在描述SMA相对于其他皮层区域的时间动态。SMA和前辅助运动区是提示开始后最早激活的区域之一，在发音开始前活动达到峰值，并且是预测每次试验反应时间的最早区域。SMA和前辅助运动区单个电极处的神经活动与言语起始密切相关；对于任何给定的试验，活动在刺激开始后一个高度可预测的时间开始，并持续到言语开始。我们的结果支持SMA是言语起始网络中的关键节点这一观点。
