试着翻译看看:P --- How the Brain Localizes Sounds 大脑如何分辨声音的位置 We live in a world full of echoes. Sounds reverberate, bouncing off walls, buildings, rocks and any other nearby surface. 我们住在一个充满回声的世界， 声音反射，碰撞墙壁、房子、石头以及任何附近的表面。 These sound waves pile on one another and hurtle down your ear canals from different angles, the echoes from one noise jumbling together with new sounds and their echoes. 音波持续地增强并从不同的角度冲击你的耳道，噪音产生的回声又与新的声音及其回声混 在一起。 In spite of that barrage, the neurons in the auditory midbrain, an area that responds before the auditory cortex does, are able to sort out which were the original sounds and where they came from. 尽管在这种疲劳轰炸下，在听觉皮质之前反应的中脑神经仍旧能够辨认原本的声音以及位 置。 How they do so has long puzzled scientists, but new research suggests the trick is simpler than expected. 科学家长期困惑於大脑是如何做到这件事(辨认原始的声音以及位置)， 然而新的研究结果说明了这件事其实比原本所想的简单。 In an April study, neuroscientists led by Sasha Devore at the Massachusetts Institute of Technology tested the widely held hypothesis that specialized cells in the brain actively suppress neuronal response to echoes. 在4月的研究中, 麻省理工学院的Sasha Devore带领神经科学家检查一个广泛被接受的假说: 大脑中存在特定的细胞负责抑制神经对回声产生反应。 Using electrodes in a cat’s midbrain, researchers measured cells' responses to a sound and its reverberations. 透过观测一只猫中脑的电极,检验细胞对声音以及回声的反应。 They found that the cells that sense a sound’s direction of origin responded more strongly to the first 50 milliseconds of sound waves than they did to the later waves—their activity simply tapered off after the onset of the sound. 研究者发现，细胞对於起初声音的方向跟之後的声音相比， 在前50ms的声波具有更强的反应— 细胞的活动在（新）声音产生後开始减弱。 (上面这句有点是用猜的......有错请指正 Orz) The tapering response, a much simpler mechanism than the earlier theory of suppression, allows the brain to easily tune in to original sounds and pinpoint who or what is making noise. 与早期的抑制理论相比简单许多的减弱机制， 使大脑更容易地注意原本的声音并且关注是谁或者是什麽产生它。 --

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