CORTICOTHALAMIC INPUT TO THE MOTOR THALAMUS

皮质丘脑对运动丘脑的输入

• 批准号: 7349370
• 负责人: MARJORIE E ANDERSON
• 金额: $ 13.2万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7349370
• 关键词: CORTICOTHALAMIC; INPUT; MOTOR; THALAMUS

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Neurons in the motor thalamus receive input from the cerebral cortex, in addition to the basal ganglia or the cerebellum. The signals carried by corticothalamic afferents are not well known, however, nor are the non-sleep related conditions in which motor thalamic neurons shift between irregular and burst discharges. After MPTP-induced hemiparkinsonism, monkeys fail to work with the arm contralateral to the injection, and the thalamus also shows more bursts, even when the animal works with the ipsilateral arm. We have shown that there are two different classes of antidromically identified corticothalamic neurons, one of which is active in association with movement, has short antidromic latencies, is activated by low stimulus intensities, and is encountered at relatively more superficial depths (active neurons). The second has long antidromic latencies, higher threshold stimulus intensities, deeper location in cortical tracks, and no activity, except when activated antidromically. What activates these 'inactive' corticothalamic neurons is still a mystery, since we have been unable to activate them during sleep/wake transitions or different task learning states. Another paper describes the directional tuning curve of thalamocortical neurons during arm movements and compares it to the curve for motor cortex neurons activated orthodromically or antidromically by stimulation in the thalamus. Cortical tuning curves are narrower than are thalamocortical ones, suggesting that cortical connections- local or longer distance cortico-cortical- sharpen the response field of motor cortex cells. Two monkeys have been trained on a visual attention task that varies attention by varying the luminance change that animals must detect in the right or left hemifield to trigger an arm movement. We have begun to record from the thalamus of one monkey to map out the motor thalamus and then to study the activity of these neurons during different attention states, pre- and post treatment with MPTP.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。运动丘脑中的神经元除了接受来自基底神经节或小脑的输入外，还接受来自大脑皮层的输入。然而，皮质丘脑传入神经所携带的信号并不为人所知，运动丘脑神经元在不规则放电和爆发性放电之间转换的非睡眠相关条件也不为人所知。在MPTP诱导的偏侧帕金森病后，猴子不能用注射对侧的手臂工作，丘脑也显示出更多的爆发，即使动物用同侧手臂工作。我们已经表明，有两种不同类型的逆行识别的皮质丘脑神经元，其中一种与运动相关，具有短的逆行潜伏期，被低刺激强度激活，并且在相对更浅的深度（活动神经元）遇到。第二个有长的逆向laeromic，更高的阈值刺激强度，更深的位置在皮层轨道，并没有活动，除了当激活逆向。是什么激活了这些“不活跃”的皮质丘脑神经元仍然是一个谜，因为我们无法在睡眠/清醒过渡或不同的任务学习状态下激活它们。 另一篇论文描述了在手臂运动过程中丘脑皮层神经元的方向调谐曲线，并将其与丘脑中刺激顺向或逆向激活的运动皮层神经元的曲线进行了比较。皮质调谐曲线比丘脑皮质的窄，这表明皮质连接-局部或较长距离的皮质-皮质-锐化运动皮质细胞的反应场。 两只猴子接受了一项视觉注意力任务的训练，该任务通过改变动物必须在右半野或左半野检测到的亮度变化来改变注意力，以触发手臂运动。我们已经开始记录一只猴子的丘脑，绘制出运动丘脑，然后研究这些神经元在不同注意状态下的活动，MPTP治疗前后。