Step aside killer zombies: scientists have delved deep into ancient brain ­circuits to reveal neurons that can turn mild-mannered mice into ferocious predators — before switching the rodents back to their normal placid selves.

让僵尸杀手靠边站吧：科学家们对古老的大脑回路进行了深入研究，以揭示可能把性情温和的老鼠变成凶猛的掠食者的神经元，然后让这些老鼠重新变成通常的温和型。

The researchers at Yale University used “optogenetic” technology, which switches specific neurons on and off in genetically engineered animals using laser light, to tap into brain mechanisms that control predatory hunting.

耶鲁大学(Yale University)研究人员利用“光遗传”技术(利用激光开启和关闭转基因动物的特定神经元)进入控制掠食性狩猎的大脑机制。

“We’d turn the laser on and they’d jump on an object, hold it with their paws and intensively bite it as if they were trying to capture and kill it,” said Ivan de Araujo, lead investigator.

首席调查员伊万•德阿劳约(Ivan de Araujo)表示：“我们开启激光后，它们会突然跃上一个物体，用它们的爪子抓住，用力咬它，就好像它们想抓住并杀死它。”

The mice attacked not only live prey such as crickets, which they immediately devoured, but also inanimate objects such as mobile plastic toys that they would normally avoid.

这些老鼠袭击的不仅是蟋蟀等活的猎物(它们会直接吞下)，还会袭击没有生命的物体(例如它们通常会避开的移动塑料玩具)。

The study, published in the journal Cell, was part of a broader programme to research feeding behaviour in animals. The investigation of various brain regions showed that the central nucleus of the amygdala was closely associated with the urge to hunt and with controlling the jaw and neck muscles required to subdue and kill prey.

研究论文发表在《细胞》(Cell)杂志上，是研究动物进食行为的更广泛计划的一部分。对不同大脑区域的研究显示，杏仁体区域的中央神经元与猎食欲望以及控制下颌和颈部肌肉(制服并杀死猎物所需)密切相关。

By manipulating brain cells in this region through optogenetics, the Yale team found one distinct set of neurons controlled pursuit and another controlled the kill. If the hunting neurons were switched on and the biting set inactivated, the mice pursued prey but could not deliver the killer bite to finish it off.

通过光遗传技术来操控这个大脑区域的脑细胞，耶鲁大学研究团队发现，一套神经元控制追逐，另一套则控制杀戮。如果启动追逐神经元，但不启动咬食神经元，老鼠会追上猎物，但无法咬死后者。

The next stage in the Yale project will be to explore how sensory inputs — from the eyes, nose and ears — into the amygdala trigger predatory behaviour and co-ordinate its pursuit and killing modules. “We now have a grip on their anatomical identities, so we hope we can manipulate them even more precisely in the future,” said Prof de Araujo.

耶鲁大学研究项目的下一个阶段将是探索进入大脑杏仁体区域的感官信息(来自眼睛、鼻子和耳朵)如何触发掠食行为，并协调追逐和杀戮模块。德阿劳约教授表示：“我们现在了解了它们的解剖学特点，因此我们希望未来能够更精准地操控它们。”

The brain mechanisms involved are ancient. He said the ability to hunt was a “major evolutionary advantage”, pointing to the evolution of jaws in vertebrates, which began with fish about 400m years ago.

研究涉及的是古老的大脑机制。他表示，猎食能力是一项“重大进化优势”，他指出脊椎动物下颌的进化，这起始于大约4亿年前的鱼类。

The Yale research could have practical applications, such as treating neurological diseases. Researchers in mobile robotics and artificial intelligence could also use information from the predatory brain to create a device that pounces on a moving target, Prof de Araujo added.

耶鲁大学的研究可能具有实际应用空间，例如治疗神经疾病。德阿劳约教授补充称，研究移动机器人和人工智能的人员也可以利用来自大脑掠食区域的信息，创建一种扑向移动目标的设备。

But the production of killer zombie mice is not on the agenda.

但是制造杀人僵尸老鼠不在议程上。