评论
打印
It's easy to look at a sleeping dog, legs twitching as she snoozes, and imagine she's dreaming of chasing rabbits.
我们经常能够看到一只正在睡觉的狗，它在打盹时腿在抽动，想象它在追逐兔子。
And it's only natural for us humans to wonder if other animals dream. But dogs' brains are relatively similar to ours.
我们人类很自然地想知道其他动物是否也会做梦。但是狗狗的大脑和人类的相对相似。
What about something way more different from us? Say, a fish?
那些大脑和人类不太相似的动物呢？比如鱼？
We don't yet know exactly why our brains race through fantastical or scary scenarios at night,
我们还不知道为什么我们的大脑会在晚上上演幻想或可怕的场景，
but there are plenty of hypotheses. Dreams may be ways for our brains to process emotions or memories,
但是有很多的假设。梦可能是我们大脑处理情感或记忆的方式，
or to prepare for new scenarios. Human sleep occurs in a series of cycles.
或者是为新的情景做准备的方式。人类的睡眠有一系列的周期。
We cycle through a series of phases over the course of the night, which can take anywhere from 70 to 120 minutes.
我们一晚上会经历一系列的阶段，大概需要70到120分钟。
Most dreams occur during a phase called rapid eye movement, or REM.
大多数梦都发生在快速眼动（REM）阶段。
As you might imagine, this type of sleep is characterized by rapid movements of our eyes.
你可以想象，这种睡眠的特点是眼睛快速运动。
It's possible these eye movements are connected to our dreams themselves.
这些眼部运动可能与我们的梦境本身有关。
Researchers have suggested that each flick of the eye may correlate with a new image being encountered in a dream.
研究人员认为，眼睛的每一次转动都可能与梦中出现的新图像有关。
But do other animals experience sleep the way we do? Well, we can't exactly ask them, but we sure are curious.
但是动物也会和人一样做梦吗？动物不会说话，我们又很好奇。
And this fascination has led us to study sleep in fish as far back as 1913.
这种迷恋使人类早在1913年就开始研究鱼类的睡眠。
That study set out behavioral criteria for fish sleep.
该研究设定了鱼类睡眠的行为标准。
In zebrafish, that means things like immobility, a preferred sleeping location, and a reduced respiratory rate.
对斑马鱼来说，这意味着静止不动，一个更好的睡觉地点，以及呼吸频率的降低。
But it wasn't until a 2019 study that anyone defined what was happening inside the brains of fish while they sleep.
但直到2019年的一项研究，人们才定义了鱼类睡觉时大脑里发生了什么。
And it took so long because it's hard to do! One way to look inside human brains, including during sleep,
花了这么长时间是因为很难啊！探究人类大脑，包括在睡眠中的大脑
is using an instrument called an electroencephalogram, or EEG.
的一种方法是使用一种被称为脑电图（EEG）的工具。
This typically measures activity in a region of the brain called the neocortex. Fish don't have a neocortex.
它通常测量大脑中一个叫做新皮质的区域的活动。鱼类没有新皮质。
However, zebrafish do have something similar, called the dorsal pallium, which the researchers targeted in this study.
但斑马鱼有类似的东西——背侧大脑皮层，研究人员在研究中将这个锁定为目标。
They took advantage of the fact that the young zebrafish are see-through.
他们利用了年轻的斑马鱼是透明的这一事实。
You can see straight into their brains! They inserted a gene into the fish that caused their neurons to glow when active.
你可以看见它们的大脑！他们在鱼体内植入了一种基因，这种基因可以使鱼的神经元在活动时发光。
Specifically, it gives off light in response to calcium. Since calcium levels change as neurons send their signals,
具体来说，它在钙的作用下发光。由于钙离子水平会随着神经元发出的信号而变化，
this allowed the researchers to watch brain activity while the fish slept.
这使得研究人员能够在鱼睡觉时观察它们的大脑活动。
Their results showed that like humans, fish cycle through sleep patterns.
他们的研究结果表明，和人类一样，鱼类也有睡眠模式。
The researchers saw two main sleep states: slow bursting sleep and propagating wave sleep.
研究人员发现了两种主要的睡眠状态：慢脉冲睡眠和传播波睡眠。
And propagating wave sleep showed a number of similarities to our own REM phase, though the fish's eyes stayed still.
尽管鱼的眼睛保持静止，但传播波睡眠与人类的REM阶段有许多相似之处。
The researchers suggested these similar patterns of sleep activity could have evolved before fish and humans split,
研究人员认为，这些类似的睡眠活动模式可能在4.5亿年前
more than 450 million years ago. So, this doesn't prove that fish can dream,
鱼类和人类分裂之前就已经进化出来了。所以这不能证明鱼也做梦，
but it suggests that they do go through something similar to our own dream-filled REM sleep.
但这表明它们确实经历了类似于我们自己充满梦境的快速眼动睡眠。
So, that means fish dreams are a possibility! Thanks to our patron Olan Kenny for asking this question.
所以这意味着鱼有可能做梦！感谢Olan Kenny的提问。
Our patrons submit and vote on questions that eventually get made into episodes like this one!
我们的赞助人提交问题并为问题投票，最终本期视频得以出产！
So, if you want to be a part of that process, or just want to help SciShow keep making free educational videos
所以，如果你也想参与其中，或只想帮助我们只做免费教育视频
for everyone you can check out patreon.com/scishow.
你可以去patreon.com/scishow看看。
