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This is Scientific American's 60-second Science, I'mSusanne Bard¹.

这里是科学美国人——60秒科学系列，我是苏珊娜·巴德。

It's not easy to study the early development of thehuman brain.

研究人脑的早期发育并不容易。

"The brain is very inaccessible², especially the earlyfetal stages. It's just not ethical³ to study normal, healthy human brains."

“大脑很难进入，尤其是胎儿早期。研究正常健康的人脑是不道德的。”

University of California, San Diego, biologist Alysson Muotri. He says researchers have insteadrelied on animal models.

加州大学圣地亚哥分校的生物学家阿里森·穆特里说到。他表示，研究人员转而依赖动物模型。

"But the human brain is so much different from other species that we're desperate to have, really, a human model so we can study the human brain."

“但人脑与其他物种的大脑存在相当大的区别，因此我们迫切需要人类模型来研究人脑。”

Now Muotri's team may have that model, in the form of small globules of brain cells they'vecreated in the lab. These pea-sized structures develop from stem cells that are bathed in aculture of nutrients⁴, along with proteins that control gene⁵ activation⁶. As the little structuresgrow, their constituents⁷ also specialize into different types of brain cells.

现在，穆特里的团队可能拥有了这种模型，其形式是他们在实验室中创造出来的脑细胞小球。这些豌豆大小的结构由干细胞发育而来，而这些干细胞浸泡在营养物质和控制基因激活的蛋白质培养物中。随着这些小结构的成长，其成分也会分化成不同类型的脑细胞。

"And they will form connections, and these connections will form functional⁸ synapses⁹ that will, later on, turn into networks."

“它们会形成连接，这些连接会形成功能性突触，突触随后会联成网络。”

After two months, the mini brains even begin to emit brain waves.

两个月后，微型大脑甚至会开始释放脑电波。

"And you can record every week to see how the activity has changed. And when they reachabout six months of age, we see a growth exponentially in the number of connections andsynapses that they can make."

“你可以每周进行记录，观察活动变化。当它们长到约6个月大时，其能形成的连接和突触数量呈指数级增长。”

And at around 10 months, their brain activity compares to that of premature¹⁰ human infants.

在大约 10个月大的时候，其大脑活动与早产儿类似。

"They're pretty much following the same trajectory¹¹ as the human brain does."

“微型大脑的发育轨道与人脑非常相似。”

That could make the mini brains very useful for understanding how our brains become wiredearly on. And they could also provide insights into the development of neurological conditionssuch as autism and epilepsy.

这可能使微型大脑非常有助于理解人脑早期的连接形式。微型大脑还可以为自闭症和癫痫等神经系统疾病的发展提供思路。

"These very early stages are exactly when some neurological conditions appear. And we havethe possibility to help millions of people with neurological conditions."

“神经疾病往往出现在大脑发育非常早期的阶段。我们有可能帮助数百万名神经疾病患者。”

But Muotri also cautions that as the technology moves forward, ethical questions will start toemerge.

但穆特里也警告称，随着技术的进步，伦理问题将开始显现。

"Someone might ask, 'Are they conscious or are they self-aware? Can they feel pain?' I thinkwe are in a gray zone, where this technology could evolve to something more complex. Andthen I think the ethical question would be, 'What's the moral status of these miniaturizedbrains?'"

“有人可能会问，‘这些大脑有意识吗？或它们有自我意识吗？它们能感受到疼痛吗？’我认为我们处于技术可进化出更复杂事物的灰色地带。之后的伦理问题将是，‘这些微型大脑的道德地位如何？’”

Muotri says that same question has formed the basis for the rules and regulations governing theuse of animals in the lab, which can serve as a model to guide the mini brain research. Thefindings are in the journal Cell Stem Cell.

穆特里表示，同样的问题构成了在实验室使用动物的规章制度的基础，而这可以作为引导微型大脑研究的范例。研究结果发表在《细胞·干细胞》期刊上。

In addition to shedding light on neurological development, mini brains could also helpreveal how the human brain evolved and play a role in improving algorithms for artificialintelligence. These pea-sized brains may produce some big insights.

除了阐释神经发育，微型大脑还有助于揭示人类大脑的进化方式，并在改善人工智能算法方面发挥作用。这些豌豆大小的大脑可能会催生一些重大的见解。

Thanks for listening for Scientific American — 60-Second Science. I'm Susanne Bard.

谢谢大家收听科学美国人——60秒科学。我是苏珊娜·巴德。