Top-down gain control of the auditory space map by gaze control circuitry in the barn owl.
Top-down gain control of the auditory space map by gaze control circuitry in the barn owl.
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通过仓鸮中的凝视控制电路对听觉空间图进行自上而下的控制。
DOI：
10.1038/nature04411
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发表时间：
2006
期刊：
影响因子：
64.8
通讯作者：
Knudsen,EricI
中科院分区：
文献类型：
--
作者：
Winkowski,DanielE;Knudsen,EricI
大脑中控制注视方向的高级回路与视觉空间注意力的控制密切相关，。在动物将目光指向刺激之前，对视觉刺激的心理物理敏感性和大脑皮层中代表刺激的高级神经元的反应性都急剧增加。等效的行为敏感性和视觉刺激的神经元反应性的结果，从局部电微刺激的凝视控制中心在猴子，。凝视控制系统是否调节视觉以外的感觉方式中的神经元反应尚不清楚。在这里，我们表明，电微刺激施加到谷仓猫头鹰前脑的凝视控制电路调节中脑听觉反应的增益在一个注意力的方式。当前脑回路被激活时，中脑对由前脑位点编码的位置处的听觉刺激的反应增强，空间选择性变尖锐。同样的刺激抑制了对听觉刺激的反应，这些听觉刺激在中脑地图的其他位置上表现出来。仓鸮的凝视控制电路对听觉反应的这种空间特异性、自上而下的调节表明，中枢神经系统使用一种共同的策略来动态调节感官增益，这种策略适用于各种形式、大脑区域和脊椎动物物种。这种方法为发现中枢神经系统中自上而下的增益控制机制提供了一条途径。
High-level circuits in the brain that control the direction of gaze are intimately linked with the control of visual spatial attention,,,,. Immediately before an animal directs its gaze towards a stimulus, both psychophysical sensitivity to that visual stimulus and the responsiveness of high-order neurons in the cerebral cortex that represent the stimulus increase dramatically,,. Equivalent effects on behavioural sensitivity and neuronal responsiveness to visual stimuli result from focal electrical microstimulation of gaze control centres in monkeys,,,. Whether the gaze control system modulates neuronal responsiveness in sensory modalities other than vision is unknown. Here we show that electrical microstimulation applied to gaze control circuitry in the forebrain of barn owls regulates the gain of midbrain auditory responses in an attention-like manner. When the forebrain circuit was activated, midbrain responses to auditory stimuli at the location encoded by the forebrain site were enhanced and spatial selectivity was sharpened. The same stimulation suppressed responses to auditory stimuli represented at other locations in the midbrain map. Such space-specific, top-down regulation of auditory responses by gaze control circuitry in the barn owl suggests that the central nervous system uses a common strategy for dynamically regulating sensory gain that applies across modalities, brain areas and classes of vertebrate species. This approach provides a path for discovering mechanisms that underlie top-down gain control in the central nervous system.