...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Neurophysiology >Changing directions of forthcoming arm movements: neuronal activity in the presupplementary and supplementary motor area of monkey cerebral cortex.
【24h】

Changing directions of forthcoming arm movements: neuronal activity in the presupplementary and supplementary motor area of monkey cerebral cortex.

机译：即将发生的手臂运动方向改变：猴子大脑皮层的补充运动区和补充运动区的神经元活动。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

1. To understand roles played by two cortical motor areas, the presupplementary motor area (pre-SMA) and supplementary motor area (SMA), in changing planned movements voluntarily, cellular activity was examined in two monkeys (Macaca fuscata) trained to perform an arm-reaching task in which they were asked to press one of two target buttons (right or left) in three different task modes. 2. In the first mode (visual), monkeys were visually instructed to result and press either a right or left key in response to a forth coming trigger signal. In the second mode (stay), monkeys were required to wait for the trigger signal and press the same target key as pressed in preceding trials. In the third mode (shift), a 50 Hz auditory cue instructed the monkey to shift the target of the future reach from the previous target to the previous nontarget. 3. While the monkeys were performing this task, we recorded 399 task-related cellular activities from the SMA and the pre-SMA. Among them, we found a group of neuronsthat exhibited activity changes related specifically to shift trials (shift-related cells). The following properties characterized these 112 neurons. First, they exhibited activity changes after the onset of the 50-Hz auditory cue and before the movement execution when the monkeys were required to change the direction of forthcoming movement. Second, they were not active when the monkeys pressed the same key without changing the direction of the movements. Third, they were not active when the monkeys received the 50-Hz auditory cue but failed to change the direction of the movements by mistake. These observations indicate that the activity of shift-related cells is related to the redirection of the forthcoming movements, but not to the auditory instruction itself or to the location of the target key or the direction of the forthcoming movements. 4. Although infrequently, monkeys made errors in the stay trials and changed directions of the reach voluntarily. In that case, a considerably high proportion of shift-related neurons (12 of 19) exhibited significant activity changes long before initiation of the reach movement. These long-lasting activities were not observed during the preparatory period in correct stay trials, but resembled the shift-related activity observed when the target shift was made toward the same direction. Thus these activity changes were considered to be also related to the process of changing the intended movements voluntarily. 5. We found another population of neurons that showed activity modulation when the target shift was induced by the visual instruction in visual trials (visually guided shift-related neurons). These neurons were active when the light-emitting diode (LED) guided the forthcoming reach to the previous nontarget but not to the previous target. Therefore their activity was not a simple visual response to the LED per se. A majority of them also showed shift-related activity in shift trials (19 of 22 in monkey 2). 6. Neurons exhibiting the shift-related activity were distributed differentially among the two areas. In the pre-SMA, 31% of the neurons recorded showed the shift-related activity, whereas in the SMA, only 7% showed such an activity. These results suggest that pre-SMA and SMA play differential roles in updating the motor plans in accordance with current requirements.
机译：1.为了了解两个皮质运动区（前运动区（SMA）和辅助运动区（SMA））在自愿改变计划的运动中所扮演的角色，研究了两只猴子（猕猴）的细胞活动，这些猴子经过训练可以执行伸臂任务，要求他们在三种不同的任务模式下按下两个目标按钮之一（向右或向左）。 2.在第一种模式（视觉）下，视觉指示猴子进行反应，并响应于第四次触发信号而按下向右或向左键。在第二种模式（停留）中，要求猴子等待触发信号并按与先前试验相同的目标键。在第三模式（换档）中，50 Hz的听觉提示指示猴子将未来触及范围的目标从先前的目标转换为先前的非目标。 3.在猴子执行此任务时，我们记录了SMA和SMA前期的399种与任务相关的细胞活动。其中，我们发现了一组神经元，这些神经元表现出与轮班试验（轮班相关细胞）特别相关的活动变化。以下特性表征了这112个神经元。首先，它们在50 Hz听觉提示开始后和执行运动之前表现出活动性变化，要求猴子改变即将发生的运动方向。其次，当猴子在不改变运动方向的情况下按下相同的键时，它们就没有活动。第三，当猴子收到50 Hz的听觉提示时，它们没有活动，但未能错误地改变运动方向。这些观察结果表明，与班次相关的单元格的活动与即将发生的运动的重定向有关，但与听觉指令本身或与目标键的位置或即将发生的运动的方向无关。 4.虽然不常见，但猴子在中止试验中犯了错误，并自动改变了伸手的方向。在这种情况下，相当大比例的与移位相关的神经元（19个中的12个）在到达运动开始前很久就显示出明显的活动变化。在准备阶段，在正确的停留试验中未观察到这些持久的活动，但类似于当目标朝相同方向转移时观察到的与转移相关的活动。因此，这些活动变化也被认为也与自愿改变预期动作的过程有关。 5.我们发现了另一组神经元，当视觉试验中的视觉指令引起目标转变时，这些神经元显示出活动调节（视觉指导的转变相关神经元）。当发光二极管（LED）将即将到达的目标引导到先前的非目标但没有到达先前的目标时，这些神经元处于活动状态。因此，它们的活动并不是对LED本身的简单视觉响应。他们中的大多数人在轮班试验中也显示了与轮班相关的活动（猴子2中的22个中有19个）。 6.表现出与移位相关的活动的神经元在两个区域之间的分布有所不同。在SMA前期，记录的31％的神经元显示出与移位相关的活性，而在SMA中，只有7％的神经元显示出这种活性。这些结果表明，前SMA和SMA在根据当前要求更新电机计划中起着不同的作用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号