PDF(Pubmed)
Abstract：
Inhibitory interneurons within cortical layer 1 (L1-INs) integrate inputs from diverse brain regions to modulate sensory processing and plasticity, but the sensory inputs that recruit these interneurons have not been identified. Here we used monosynaptic retrograde tracing and whole-cell electrophysiology to characterize the thalamic inputs onto two major subpopulations of L1-INs in the mouse auditory cortex. We find that the vast majority of auditory thalamic inputs to these L1-INs unexpectedly arise from the ventral subdivision of the medial geniculate body (MGBv), the tonotopically-organized primary auditory thalamus. Moreover, these interneurons receive robust functional monosynaptic MGBv inputs that are comparable to those recorded in the L4 excitatory pyramidal neurons. Our findings identify a direct pathway from the primary auditory thalamus to the L1-INs, suggesting that these interneurons are uniquely positioned to integrate thalamic inputs conveying precise sensory information with top-down inputs carrying information about brain states and learned associations.
摘要：
皮质层1（L1-IN）内的抑制性中间神经元整合来自不同大脑区域的输入，以调节感觉处理和可塑性。但是招募这些中间神经元的感觉输入尚未确定。在这里，我们使用单突触逆行追踪和全细胞电生理学来表征小鼠听觉皮层中两个主要L1-IN亚群的丘脑输入。我们发现，这些L1-IN的绝大多数听觉丘脑输入意外地来自内侧膝状体（MGBv）的腹侧细分，声光组织的初级听觉丘脑。此外，这些中间神经元接收强大的功能性单突触MGBv输入，与L4兴奋性锥体神经元中记录的那些相当。我们的发现确定了从初级听觉丘脑到L1-IN的直接通路，这表明这些中间神经元具有独特的位置，可以将传达精确感觉信息的丘脑输入与携带有关大脑状态和学习关联的信息的自上而下的输入相结合。
