Midbrain local circuits shape sound intensity codes.
Midbrain local circuits shape sound intensity codes.
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DOI：
10.3389/fncir.2013.00174
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发表时间：
2013
影响因子：
3.5
通讯作者：
Sivaramakrishnan S
中科院分区：
文献类型：
--
作者：
Grimsley CA;Sanchez JT;Sivaramakrishnan S
感觉信息的分层处理需要沿外围到中枢通路的多个层次的相互作用。最近的证据表明，驱动和调制成分之间的相互作用可以影响自上而下和自下而上的感官信息处理。在这里，我们展示了从外部源继承的分量与本地分量相结合来编码声音强度。通过将高浓度的二价阳离子应用于听觉中脑下丘核的神经元，我们发现随着声音强度的增加，突触效能的来源从遗传输入转变为局部回路。在具有宽动态范围强度响应的神经元中，遗传输入在低声强时增加放电率，但在中高声强时达到饱和。局部电路在高声强下激活，并通过不断增加其输出增益来扩大动态范围。继承的输入是必要的，足以唤起调谐的响应，然而局部电路改变峰值输出。推挽驱动抑制和兴奋对强度可变神经元产生净兴奋性驱动，并使神经元适应强度。我们的研究结果表明，动态范围和调谐通过自身可变或调谐的局部电路在听觉中脑中重新出现。
Hierarchical processing of sensory information requires interaction at multiple levels along the peripheral to central pathway. Recent evidence suggests that interaction between driving and modulating components can shape both top down and bottom up processing of sensory information. Here we show that a component inherited from extrinsic sources combines with local components to code sound intensity. By applying high concentrations of divalent cations to neurons in the nucleus of the inferior colliculus in the auditory midbrain, we show that as sound intensity increases, the source of synaptic efficacy changes from inherited inputs to local circuits. In neurons with a wide dynamic range response to intensity, inherited inputs increase firing rates at low sound intensities but saturate at mid-to-high intensities. Local circuits activate at high sound intensities and widen dynamic range by continuously increasing their output gain with intensity. Inherited inputs are necessary and sufficient to evoke tuned responses, however local circuits change peak output. Push–pull driving inhibition and excitation create net excitatory drive to intensity-variant neurons and tune neurons to intensity. Our results reveal that dynamic range and tuning re-emerge in the auditory midbrain through local circuits that are themselves variable or tuned.
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DOI：
10.1007/s10162-008-0139-6
发表时间：
2009-03
影响因子：
2.4
作者：
Sumner, Christian J.;Scholes, Chris;Snyder, Russell L.
通讯作者：
Snyder, Russell L.
DOI：
10.1126/science.1194908
发表时间：
2010-11-05
期刊：
Science (New York, N.Y.)
影响因子：
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作者：
Freiwald WA;Tsao DY
通讯作者：
Tsao DY
影响因子：
1.7
作者：
Egorova, Marina;Vartanyan, Inna;Ehret, Guenter
通讯作者：
Ehret, Guenter
影响因子：
56.9
作者：
Barbour, DL;Wang, XQ
通讯作者：
Wang, XQ
影响因子：
2.5
作者：
Bartlett, EL;Wang, XQ
通讯作者：
Wang, XQ