Functional properties of single neurons in the primate face primary somatosensory cortex. II. Relations with different directions of trained tongue protrusion.
Functional properties of single neurons in the primate face primary somatosensory cortex. II. Relations with different directions of trained tongue protrusion.
复制标题
灵长类动物面部初级体感皮层单个神经元的功能特性。
作者：
Li;G. M. Murray;B. Sessle
1.在以前的论文中，我们提出的证据表明，面部初级躯体感觉皮层（SI）在舌头运动的精细控制中起着重要作用。这些发现，再加上我们早期的证据，即面部运动皮层（MI）中的许多神经元可能表现出与舌头伸出方向相关的放电率，使我们能够测试舌头伸出运动方向的变化与不同面部SI神经元活动变化相关的假设。2.两只猴子被训练在三个方向上执行舌头伸出任务：任务传感器位于中矢平面的0度，向左30度或向右30度。后两个位置被称为不对称的舌头伸出任务位置。单神经元活动记录从面对SI在试验的舌头伸出任务在每个两个或三个上述位置。此外，机械感受野（RF）划定为每个神经元。3.在研究的43个神经元中，有25个（58%）发现了方向关系;这包括20个神经元，它们在放电率上显示出显著的方向-时间相互作用，即，从实验前期到任务期，不同方向的放电频率变化有显著性差异，5不存在方向与时间的交互作用，但在伸舌任务中不同方向的放电频率有显著性差异. 4.在研究的43个神经元中，分别有21个和20个在舌头和嘴唇上有RF（“舌头RF”和“嘴唇RF”神经元），其余2个接收来自其他口面区域的机械敏感传入输入。舌RF和唇RF神经元的方向敏感性发生率无显著差异（分别为12/21和11/20）。5. 25个“定向”神经元中有8个位于3b区，17个位于1区。3b区和1区定向神经元的比例无显著差异。6.在首选方向的放电频率的增加，平均为25个定向神经元，39%以上的任务期间观察到的所有方向的舌头伸出任务的平均放电频率。八个方向性神经元表现出显着的增加，在舌头伸出任务高达130毫秒前颏舌肌肌电图活动的发病率。（400字处删节）
1. In previous papers we have presented evidence suggesting an important role for the face primary somatosensory cortex (SI) in the fine control of tongue movements. These findings, plus our earlier evidence that many neurons in face motor cortex (MI) may exhibit firing rates related to the direction of tongue protrusion, led us to test the hypothesis that variations in the direction of a tongue-protrusion movement would be associated with variations in the activity of different face SI neurons. 2. Two monkeys were trained to perform a tongue-protrusion task in each of three directions: the task transducer was positioned at 0 degrees, 30 degrees to the left, or 30 degrees to the right from the midsagittal plane. The latter two positions were termed asymmetrical tongue-protrusion task positions. Single-neuron activity was recorded from face SI during trials of the tongue-protrusion task at each of two or three of the above positions. In addition, the mechanoreceptive field (RF) was delineated for each neuron. 3. Directional relations were found in 25 (58%) of the 43 neurons studied; this included 20 neurons showing a significant direction-by-time interaction in firing rate, i.e., the change of firing rate from the pretrial period to the task period was significantly different between different directions, and 5 showing no direction-by-time interaction but a significant difference in firing rate between different directions of the tongue-protrusion task. 4. Of the 43 neurons investigated, 21 and 20 had a RF on the tongue and lips, respectively ("tongue RF" and "lip RF" neurons), and the remaining 2 received mechanosensitive afferent inputs from other orofacial regions. There was no significant difference in the incidence of directional sensitivity between the neurons with a tongue RF and those with a lip RF (12/21 and 11/20, respectively). 5. Eight of the 25 "directional" neurons were located in area 3b and 17 in area 1. There was no significant difference in the proportion of directional neurons between areas 3b and 1. 6. The increase in discharge frequency at the preferred direction was, on the average for the 25 directional neurons, 39% over the mean discharge frequency observed during the task period for all directions of the tongue-protrusion task. Eight directional neurons showed a significant increase in firing rate during the tongue-protrusion task up to 130 ms before the onset of genioglossus electromyographic activity.(ABSTRACT TRUNCATED AT 400 WORDS)