Information processing in the thalamus

描述(申请人提供)：大量的能量被用于阐明基底节的功能，但几乎对支配基底节输出通过丘脑的传递的机制一无所知。这项研究计划的基本目的是探索信息是如何通过丘脑核团传递的，丘脑核核位于斑马雀学习歌曲所需的基底节环内。这个问题很有趣，因为这个丘脑区(DLM)最重要的输入是GABA能，对DLM神经元有强烈的抑制作用。那么，DLm如何传递GABA能输入呢？丘脑神经元的一个强大特征可以使抑制性突触后电位(IPSPs)兴奋，即抑制后反弹。事实上，短时接二连三的IPSP已被证明可以在DLm神经元中引发反弹尖峰。在这项研究中，我们计划系统地探索丘脑神经元将IPSP转换为超阈值输出的能力。这些实验将提供对脊椎动物运动学习重要的丘脑区域的功能以及丘脑-基底节继电器的强大洞察力。这些信息对于完全理解基底节环路是必要的，基底节环路在帕金森氏症等人类疾病中是病理性的。

DESCRIPTION (provided by applicant): An enormous amount of energy has been targeted at elucidating basal ganglia function yet almost nothing is known about the mechanisms that govern the relay of basal-ganglia output through the thalamus. The basic thrust of this research proposal is to explore how information is transferred through a thalamic nucleus, which lies within a basal ganglia loop required for song learning in zebra finches. This problem is interesting because the most substantial input to this thalamic area (DLM), is GABAergic and strongly inhibitory to DLM neurons. How, then, might DLM relay GABAergic inputs? A robust feature of thalamic neurons could render inhibitory post-synaptic potentials (IPSPs) excitatory, namely post-inhibitory rebound. In fact, short barrages of IPSPs have been shown to elicit rebound spikes in DLM neurons. In this study, we plan to systematically explore the capacity of thalamic neurons to translate IPSPs into superthreshold output. These experiments will provide powerful insight into the function of thalamic areas important for motor learning in vertebrates, as well as thalamic-basal ganglia relay. This information is necessary to completely understand basal ganglia circuitry, which is pathological in human disorders such as Parkinson's disease.