And considering you spend roughly six years of your life dreaming, it's quite curious that we often brush them aside to be quickly forgotten.

人的一生當中，大概有六年的時間在作夢，但是相當奇怪的是，我們很容易忽視並且快速遺忘夢的內容。

Night after night, our brains go to work and bring us some of the most incredible, bizarre, and often seemingly random imagery and storylines.

我們的頭腦每天晚上運作並讓我們看見最不可思議、離奇的隨機畫面或生活片段。

But what are dreams?

而夢究竟是什麼?

And like the many science fiction stories or movies, could we ever record and figure out what we're seeing while we're dreaming?

我們能不能像許多科幻小說或電影一樣，紀錄並且解讀我們在夢中看見的畫面?

You may have heard of people referring to 'brain waves' before, but have you ever stopped to think: Are these actual waves, and do they carry information?

你可能聽過其他人談論「腦波 」，但你有沒有好奇過：腦波是真實的波嗎？ 這些波是否帶有任何訊息？

Are brain waves similar to, say, radio waves?

腦波跟無線電波一樣嗎？

The answer is, yes.

沒錯。

Both brain and radio waves are forms of electromagnetic radiation, waves that travel at the speed of light.

腦波和無線電波都是以光速傳播的電磁輻射。

Every time you think, thousands of neurons fire at the same frequency and generate a wave.

每當你在思考時，數以千計的神經元會以相同的頻率激發能量，並產生波。

These waves oscillate at around 10 to 100 cycles per second.

這些波以每秒 10 到 100 次的頻率振動。

Radio waves, on the other hand, oscillate at around 50 million to 1 billion times per second.

另一方面，無線電波每秒振動的頻率大約是五千萬次到十億次。

Scientists have long used this phenomenon to measure brain activity and interface the brain to electronic devices.

從很早以前開始，科學家們就已經根據此現象，將腦部和電子儀器做連結來偵測腦部活動。

It allows us to see which parts of the brain are active for different activities, and similarly, which parts of the brain are active during dreaming.

用電子儀器連結人腦後，我們可以觀察到腦部個別區塊針對不同活動的活躍反應，同時也可以知道腦部有哪些區塊在人作夢時特別活躍。

Strange as it may seem, we still barely understand why we sleep let alone why we dream.

雖然我們有能力觀察到腦部的反應，但我們還搞不清楚人類為什麼要睡覺，甚至作夢。

Michael from Vsauce does a fantastic job explaining the main theories for why we dream.

Vsauce 頻道的 Michael 對於人類作夢的主要理論做了一個很棒的解釋。

But there are so many theories because we can't really measure or know what people are dreaming about without waking them up and asking them.

但因為我們無法在不叫醒並詢問作夢者的狀況下知道他們正在夢些什麼，所以坊間充斥各種關於作夢的理論。

Of course, this is subject to forgetting or other errors.

不過就算你叫醒作夢者，他們也很可能因為遺忘或其他失誤而無法提供準確訊息。

Unfortunately, there is no device that exists to allow us to peer into the mind of a dreamer, or is there?

不幸的是，好像沒有任何的裝置可以允許我們窺視作夢者的腦袋。或者其實有呢？

Crazy as it sounds, scientists have created a technique to do just that.

這聽起來很瘋狂，但科學家們的確創造了一種技術來做這件事。

This mind-reading technology began with a functional MRI Scanner, inside which, subjects were shown simple pictures made up of black and white pixels.

科學家把受試者送進功能性磁振造影儀，向他們展示由簡單的黑白像素組成的圖案，再用技術讀取他們的大腦。

The software then finds patterns in the brain activity that corresponds to the specific images.

分析軟體會蒐集受試者看到不同圖案產生的腦部活躍形態。

For example, if the letter "T" was shown, the software would record exactly how the brain reacted.

舉例來說，如果受試者看到了字母「T」，分析軟體就會把腦部產生的反應記錄下來。

After sufficient data, the subjects were then shown completely different images, and the software would predict and recreate what it thought the subjects were seeing.

蒐集了充分資料後，科學家再向受試者展示完全不同的圖案，讓分析軟體預測和描繪它認為受試者看到的圖案。

After being shown the word "neuron", these were the images the software generated.

這是受試者看到單字「neuron 」後，分析軟體描繪的圖案。

But it doesn't stop there.

科學家們的測試不只是這樣。

Further studies began to use more complex visuals and started monitoring the subjects in their sleep.

他們接著使用更複雜的圖像去測試受試者，並持續檢測受試者的睡眠狀況。

In this case, they first had the subjects fall asleep while in an fMRI, and would wake them up in the middle of dreaming, quickly asking them what they were dreaming about.

在實驗中，科學家先讓受試者在 fMRI 儀器內睡著，並在受試者作夢期間叫醒他們，立刻問他們剛剛夢到的內容。

They then used thousands of images from the internet to get a best approximation of what the subject was seeing based on brain scans.

接下來，科學家使用網路上數以千計的影像，比對腦部掃描的結果，試著重建受試者夢中的畫面。

After doing this nearly 200 times with each person, and plugging the information into a learning algorithm, software was used to interpret and generate their next dreams.

在和每個受試者進行了近 200 次的試驗後，科學家將蒐集而來的資訊輸入學習演算系統中，讓分析軟體轉譯和預測受試者的下一個夢。

Though by no means perfect, it was clear that the machine's predictions were better than chance, matching up with the dreamers' description.

儘管儀器的預測並不完美，但儀器所預測的夢，卻和作夢者所描述的夢境有不少的重合。

Perhaps even more shocking is a study that used actual video footage.

還有一個更瘋狂的測試行為是科學家用影片來做夢的研究。

After showing subjects two hours of movie footage and analyzing their brain activity, they then used a library of 18 million, 1 second YouTube clips to match the brain activity.

科學家在讓受試者觀看兩個小時的電影並分析完他們的腦部活動數據後，再拿出 1800 萬個 1 秒鐘長度的 YouTube 影片片段給受試者觀看，以再次比對受試者的腦部活動數據。

Here are the results: On the left are new, unrelated clips that the subjects were later shown, and on the right is what the software guessed they were seeing, using a mashed-up combination of the YouTube clips as an approximation.

這是數據比對後，儀器產生的夢境模擬結果：畫面左邊是受試者之後觀看的全新影片，畫面右邊是儀器以 YouTube 影片庫為基礎，所預測受試者看見的畫面。

All of this based on their brain waves.

所有的預測都是根據受試者的腦波數據而產生的。

As these software programs become more and more complex, we come that much closer to accurately visualizing and recording our thoughts and dreams.

隨著分析用的儀器和程式越來越複雜，我們也許能更精準地視覺化和記錄我們的想法和夢境。

At which point, perhaps, we'll find a few more clues into why we dream, in the first place.

甚至解答人類為什麼會作夢。

And if you'd like to find out about some other amazing and unanswered scientific phenomenon, head over to AllTime 10's channel, where 10 fantastic science YouTubers have come together in an attempt to answer some burning questions.

如果你對解讀一些驚奇和未知的科學現象感興趣，鎖定 All Time 10's YouTube 頻道，我們召集了 10 位很棒的科學系 YouTuber 來一起解答熱門科學問題。

It's a super-collaboration of science! And if you're new to AsapSCIENCE, be sure to subscribe for more weekly science videos! We've made a playlist of some of our favorite and most popular videos for your viewing pleasure. Enjoy!

這可是我們的超級企劃！如果這是你第一次來到 AsapSCIENCE 頻道，訂閱我們就可以觀看我們週更的科學影片囉！我們也把精彩和熱門的前期影片整理成播放清單，方便你觀看。慢用！