What are your plans for this weekend?

你這週末有什麼規劃？

Where do you see yourself in five years?

你五年後會過著怎樣的生活？

Answering these questions requires looking into the future.

要回答這些問題都必須想到未來。

But when you make these predictions, what you're actually doing is accessing your memories.

但當你在預知未來時，你其實是在搜尋回憶。

Being able to accurately predict the future gives humans an evolutionary advantage.

能夠精準預測未來的能力給予人類革命性的優勢。

I'm not talking about a fortune cookie or a horoscope that says your true love will find you next Tuesday.

我不是說那種曲奇餅乾或星座運勢說你下禮拜二會遇見真愛的那種「預言」。

I'm talking about the practical ability to anticipate when crops will be ready to harvest or to prepare for a meeting with your boss.

我是說實際可以預測作物何時能收成或預先準備跟老闆開會的那種「預知」。

Planning beyond the present moment and even years into the future is indispensable to human life in society.

提前為幾年之後的未來做打算對人類社會來說是必須的。

But how do we do it?

但我們是怎麼做到的呢？

Researchers believe that we rearrange our memories of the past to put together a vision of what the future might look like.

研究者相信我們會重新整理我們的記憶並組織成可能的未來景象。

They've discovered that memories and predictions take place in the same regions of the brain and appear to use the same underlying processes.

他們發現記憶和預測用的是頭腦中的同一個區域，也是用同一種方式。

Scientists first learned about this connection by observing amnesia patients.

科學家一開始是在觀察失憶患者時發現其中的關連。

Not only were these patients unable to access their memories, but they also didn't have any idea of what they might do in the future.

這些患者不只無法連結記憶，他們也對自己未來會做什麼事完全不知曉。

More recently fMRI studies have allowed researchers to see into the brains of healthy people while they remembered the past and predicted the future.

近期的功能性磁振造影研究讓學者看見腦部健康的人在回憶和預測未來時腦內所進行的活動。

The psychologist Carl Spooner observed that the activity in the brain during both tasks was almost completely overlapping.

心理學家 Carl Spooner 發現做這兩件事情時的腦內活動幾乎重疊。

Researchers have also found that as people age and start to develop memory loss, their ability to imagine the future declines as well.

研究者也發現，隨著人類年紀增加且開始記憶衰退時，他們預測未來的能力也跟著下降了。

This ability to envision moments in both the past and the future is known as mental time travel.

這個能想像過去和未來的能力又稱之為「心理時光之旅」。

Mental time travel is different from just remembering facts.

心理時光之旅與能記得事實的能力不一樣。

It's about reliving scenes in your mind.

它跟在心裡重新回顧景象有關。

If you think about the last time you went to the beach your brain reconstructs the setting.

當你想起你上一次去海邊玩時你的頭腦會開始重置當時的景象。

You feel the sunshine on your skin and the sand between your toes and you can smell the salt on the breeze.

你會感覺到陽光灑在身上、沙子在你的腳趾間，甚至可以聞到空氣中的鹹味。

In a similar way, when you imagine an event in your future, you're essentially pre-living it.

相同地，當你想像未來的事情時，你基本上就是預先在腦中做這件事情。

You construct a similar scene using details from your memory.

你用過去的回憶建造相似的景象。

So the next time you plan a beach trip, you can imagine the feel of the sun in the sand before you've even packed your sunscreen.

所以下一次你計畫要去海邊旅行時，你可以在打包防曬乳之前就先想像太陽與沙灘的感覺。

Likewise, if you're imagining your future wedding, you'll probably cherry-pick elements from weddings you've been to as well as weddings you've seen on TV and movies or in magazines.

相同地，當你想到你未來的婚禮時，你可能會從你參加過的婚禮或電視、電影、雜誌中看過的婚禮中挑出幾個過程去想像。

But the ability to predict the future using your memories does have one big disadvantage.

但擁有用過往記憶去預知未來的能力有一個很大的缺點。

People often expect the future to be too much like the present.

那就是人類期望中的未來通常與現況太相像。

Studies back up the conventional wisdom that if you go to the grocery store when you're hungry, you'll buy too much food, not realizing you won't always be this hungry.

以前一句明智的俗話可以支持這個說法，那就是當你很餓的時候去逛超市，你會買太多東西，不會想到你不是一直都這麼餓。

Similarly, if you try to predict how you'll feel in the future about something, you're likely to be blinded by your current emotions.

同樣地，如果你試著預想你未來會有什麼樣的感覺，你通常會被你現在的心情給蒙蔽。

For a vivid example of how future predictions are affected by the present, just watch an old sci-fi movie.

以前一部科幻電影就是在描述對未來的想像被現況影響的生動例子。

Take Back to the Future 2, which was made in 1989 and set in 2015.

1989 年的電影《回到未來 2》的背景設定在 2015 年。

It successfully predicted things like videoconferencing, drones, and facial recognition, but it assumed people would be still be using fax machines and pay phones.

它成功預知視訊開會、空拍機、臉部偵測，但它還認為人們會繼續用傳真機和投幣式電話。

Two technologies integral to life in the '80s which the filmmakers seemingly couldn't imagine a future without.

這兩樣科技是 1980 年代不可或缺的，所以製作電影的人們沒辦法想像未來沒有它們。

The future is always going to be full of surprises we can't predict.

未來總是充滿我們不能預知的驚喜。

But one thing's for sure, without our memories, we'd be totally in the dark.

但有一件事是確定的，假如我們沒有記憶，我們就會被蒙在鼓裡。

This is You Are Here, a series about the science behind everyday life.

這個節目是 You Are Here ，一個跟日常生活科學有關的系列節目。

Tell us what topics you'd like us to discuss in the comments.

留言跟我們說你想要我們討論的主題。

I'm Julie Beck, thanks for watching.

我是 Julie Beck ，感謝你的收看。