科学家们在实验室中发现了来自“迷你大脑”的脑电波

For the first time, brain tissue grown in a lab has spontaneously exhibited electrical activity, and it looks startlingly similar to human brain activity. More specifically, it resembles the brain activity of premature babies.

在实验室中生长的脑组织第一次自发地表现出电活动，它看起来与人类大脑的活动惊人地相似。更具体地说，它类似于早产儿的大脑活动。

This is a huge discovery that brings on possibilities for studying the early development of brain disorders.

这是一个巨大的发现，为研究大脑疾病的早期发展带来了可能性。

It also has left some scientists feeling hesitant.

这也让一些科学家感到犹豫。

These lab-grown brains are known as organoids - three-dimensional, miniature, simplified versions of organs grown in a lab for research purposes, such as testing drug responses, or cell development under certain adverse conditions.

这些实验室培养的大脑被称为“类器官”——实验室培养的用于研究目的的器官的三维、微型、简化版本，例如测试药物反应或在某些不利条件下细胞发育。

The research was first presented at a conference back in November 2018, and has now been peer-reviewed and published in Cell Stem Cell.

这项研究最初是在2018年11月的一次会议上提出的，现在已经被同行评审并发表在《细胞干细胞》杂志上。

"The level of neural activity we are seeing is unprecedented in vitro," says neuroscientist Alysson Muotri from the University of California, San Diego.

“我们在体外看到的神经活动水平是前所未有的，”加州大学圣迭戈分校的神经学家阿里森·穆特里(Alysson Muotri)说。
"We are one step closer to have a model that can actually generate these early stages of a sophisticated neural network."

“我们离建立一个能够生成复杂神经网络早期阶段的模型又近了一步。”

Muotri has been developing brain organoids in his lab for some years, but this is the first time he and his team have seen anything like human brain activity.

穆特里已经在他的实验室里开发了几年大脑器官，但这是他和他的团队第一次看到类似人类大脑活动的东西。

They grew the organoids in question from human pluripotent stem cells, or stem cells that can become any other kind of cell. They induced these 'blanks' to develop into cells that make up the cerebral cortex, the region of the brain responsible for really important things like memory, perception, cognition, thought, and sensory processing.

他们从人类多能干细胞(也就是可以成为任何其他类型细胞的干细胞)中培养出有问题的类器官。他们诱导这些“空白”发育成构成大脑皮层的细胞，大脑皮层是大脑中负责诸如记忆、感知、认知、思维和感官处理等真正重要事物的区域。

You can see a cross-section of one of the organoids below.

你可以看到下面某个有机物的横截面。
Hundreds of these tiny brains were grown in culture over a period of 10 months, with testing to ensure the right genes for brain development were being expressed. They also continuously monitored the organs with electroencephalography (EEG).

在10个月的时间里，数百个这样的小大脑在培养皿中生长，通过测试来确保大脑发育的正确基因得到表达。他们还用脑电图(EEG)连续监测这些器官。

By six months, Nature reports, the brainlets were showing very energetic brain activity - much more than any the team had noted before.

据《自然》杂志报道，到了6个月，这些脑小脑显示出非常活跃的大脑活动——这比研究小组之前所注意到的要多得多。

On analysis, the activity wasn't much like the organised, predictable brain activity of an adult. But it did bear a semblance to a different kind of brain activity. It had patterns in common with the chaotic bursts of synchronised brain activity seen in preterm infants.

据分析，这种活动与成年人有组织的、可预测的大脑活动不太相似。但它确实表现出一种不同的大脑活动。它与早产儿大脑同步活动的混乱爆发有着共同的模式。

"While network activity from organoids does not exhibit the full temporal complexity seen in adults, the pattern of alternating periods of quiescence and network-synchronised events is similar to electrophysiological signatures present in preterm human infant EEG," the researchers wrote in their paper.

研究人员在他们的论文中写道:“虽然来自类器官的网络活动，不像成年人那样呈现出完全的时间复杂性，但静息期和网络同步事件交替出现的模式，与早产儿脑电图中的电生理特征类似。”

It wasn't exactly the same. But a machine learning model trained on preterm EEG signatures was able to identify many features in common with a normal developmental timeline. Past 28 weeks, the organoids seemed to be on a similar developmental trajectory as a preterm baby of the same age.

这完全不一样。但是，一个经过早产儿脑电图特征训练的机器学习模型，能够识别出许多与正常发育时间表相同的特征。在过去的28周里，类器官似乎和同年龄的早产儿有着相似的发育轨迹。

The brain organoids are not quite like the parts of actual human brains - not only are they scaled down and simplified, the also don't have other brain regions to connect to. They were also engineered to be deficient in a proteinthat's essential for the normal function of neurons.

类脑器并不完全像人类大脑的各个部分——它们不仅被缩小和简化了，而且也没有其他大脑区域可以连接。他们还被设计成缺乏一种对神经元正常功能至关重要的蛋白质。

But they could represent a step towards a better understanding of brain development, since the brains of premature babies aren't exactly easy to come by, and adult brains are notoriously complicated.

但它们可能代表着朝着更好地理解大脑发育迈出的一步，因为早产儿的大脑并不容易获得，而成人的大脑是出了名的复杂。

"While we do not claim functional equivalence between the organoids and a full neonatal cortex," the researchers wrote, "the current results represent the first step towards an in vitro model that captures some of the complex spatiotemporal oscillatory dynamics of the human brain."

研究人员写道：“虽然我们不主张器官和完整的新生儿皮层之间的功能等效，但目前的研究结果代表了向体外模型迈出的第一步，该模型捕捉了人类大脑复杂的时空振荡动力学。”

The researchers are going to continue to try to develop the brainlets further to see if they continue to mature.

研究人员将继续尝试进一步开发大脑，看看他们是否会继续成熟。

But others are genuinely concerned at the proximity of developing consciousness in a tub of culture in a lab. So far, none of the brains show any signs of consciousness, but as the experiment continues, it could be a possibility.

但是有些人真正关心的是，在实验室的培养盆中培养意识的接近性。到目前为止，没有大脑显示出任何意识的迹象，但是随着实验的继续，这可能是一种可能性。

"The closer they get to the preterm infant, the more they should worry," neuroscientist Christof Koch of the Allen Institute for Brain Science in Seattle told Nature back in November 2018, when the research was presented at .

西雅图艾伦脑科学研究所的神经学家克里斯托夫·科赫(Christof Koch)于2018年11月向《自然》杂志表示：“他们越接近早产儿，就越应该担心。”

Given the careful engineering of the organoids to inhibit normal function, the researchers are not worried at this stage. However, if any start to show signs of consciousness, they will consider shutting the project down.

考虑到有机物对抑制正常功能的精心设计，研究人员在此阶段并不担心。然而，如果一旦开始表现出意识的迹象，他们会考虑关闭项目。

The research has been published in Cell Stem Cell.

这项研究发表在《细胞干细胞》杂志上。