憂鬱症的科學：英語精讀講義

With over 350 million people affected by depression worldwide, 文法

全球有超過3.5億人受到憂鬱症影響，

it's no doubt an incredibly real and serious issue.

毫無疑問，這是一個非常真實且嚴重的問題。

But what exactly is going on inside of a depressed person? 片語動詞

但憂鬱症患者體內究竟發生了什麼事？

Is there a biological basis for these intense feelings of sadness? 片語搭配

這些強烈的悲傷感受有生物學基礎嗎？

In the past, depression was often described as simply a chemical imbalance in the brain. 用詞

過去，憂鬱症常被簡單描述為大腦中的化學物質失衡。

Specifically, scientists believed that a lack of the neurotransmitter serotonin was to blame, 片語搭配

具體來說，科學家認為罪魁禍首是神經傳導物質血清素不足，

which is often referred to as the feel-good chemical. 片語搭配

血清素常被稱為「讓人感覺良好的化學物質」。

However, the only real evidence for this was that when some depressed people were prescribed drugs which increased serotonin levels,

然而，唯一真正的證據是：有些憂鬱症患者服用能提高血清素濃度的藥物後，

it helped alleviate their symptoms. 片語搭配

症狀有所緩解。

But while chemicals most certainly are involved, 文法

不過，雖然化學物質肯定參與其中，

this view doesn't really capture just how complex depression is. 文法

這種觀點卻無法真正呈現憂鬱症究竟有多複雜。

In recent years, scientists began to notice that the brain cell growth and connections may actually play a larger role. 片語搭配

近年來，科學家開始注意到，腦細胞的生長與連結其實可能扮演更重要的角色。

When we look at the brain of a depressed person,

當我們觀察憂鬱症患者的大腦時，

studies show that the hippocampus tends to be much smaller than average. 文法

研究顯示，他們的海馬迴往往比平均小得多。

Other areas of the brain are also physically affected,

大腦其他區域的生理結構也會受到影響，

but this region in particular controls memory and emotion.

但這個區域尤其負責控制記憶與情緒。

And the longer a person has been depressed, 文法

而且，一個人罹患憂鬱症的時間越長，

the smaller the hippocampus becomes.

海馬迴就會變得越小。

The cells and networks literally deteriorate.

其中的細胞與神經網路真的會退化。

It turns out that stress may actually be a main trigger in the decrease of new neurons in this area of the brain. 片語搭配

事實證明，壓力可能正是導致大腦這個區域的新生神經元減少的主要誘因。

In fact, studies have shown that when this region of the brain is regenerated and new neurons are stimulated,

事實上，研究顯示，當大腦的這個區域再生、新神經元受到刺激時，

mood improves.

情緒就會改善。

Interestingly, many modern drugs, including those which affect serotonin levels,

有趣的是，許多現代藥物，包括會影響血清素濃度的藥物，

have an indirect effect on the growth of brain cells. 片語搭配

都會間接影響腦細胞的生長。

This is likely why serotonin-based drugs seem to help some patients, 表達脈絡

這很可能就是為什麼針對血清素的藥物似乎對某些患者有效，

but not for the reasons we once thought. 表達脈絡

但原因並不是我們過去所想的那樣。

Instead, they promote the release of other chemicals which ultimately stimulate neurogenesis or the growth of new neurons. 片語搭配

相反地，這些藥物會促進其他化學物質釋放，最終刺激神經新生，也就是新神經元的生長。

Knowing this, some scientists now believe focus should be on drugs which directly affect neurogenesis. 講解

了解這一點後，有些科學家如今認為，重點應放在會直接影響神經新生的藥物上。

But while your neurons and chemicals may be the direct influencers,

不過，雖然神經元與化學物質可能是直接的影響因素，

many genetic factors have been discovered as well.

研究也發現了許多遺傳因素。

One particular study found that a variation in the serotonin transporter gene leaves individuals more vulnerable to depression. 文法

其中一項研究發現，血清素轉運體基因的一種變異會讓人更容易罹患憂鬱症。

Every individual has two copies of the gene,

每個人都有這個基因的兩個副本，

one from each parent,

分別來自父母雙方，

and this gene can either be short or long.

而這個基因可以是短型，也可以是長型。

After tracking 800 young adults over 5 years,

在追蹤800名年輕人5年後，

the study revealed that 33% of individuals with one short version became depressed after stressful life events,

研究發現，帶有一個短型基因的人當中，有33%在經歷充滿壓力的生活事件後罹患憂鬱症，

and people with two short genes fared even worse. 用詞

而帶有兩個短型基因的人情況更糟。

On the other hand, 表達脈絡

另一方面，

those with two long genes were much less likely to become depressed with similar life stress. 文法

帶有兩個長型基因的人，在承受類似生活壓力時，罹患憂鬱症的可能性低得多。

Many other genes have been identified which increase the likelihood of depression too, 片語搭配

研究人員還發現了許多其他會提高憂鬱症風險的基因，

and it makes sense when you consider that depression and bipolar disorder both run in families. 慣用語

考量到憂鬱症與雙相情緒障礙都有家族遺傳傾向，這也就說得通了。

Studies of identical twins show that if one has bipolar disorder, 文法

同卵雙胞胎研究顯示，如果其中一人罹患雙相情緒障礙，

the other has a 60 to 80% chance of developing it too.

另一人也有60%至80%的機率罹患這種疾病。

So, while the true cause or causes of depression have yet to be pinned down precisely, 講解

所以，儘管憂鬱症真正的病因目前仍未被精確確定，

and trust us, there's a huge list of other variables that studies suggest may come into play, 慣用語

而且相信我們，研究顯示可能參與其中的其他變因還有一長串，

it's important to remember that depression is a disease with a biological basis

但請務必記住，憂鬱症是一種具有生物學基礎的疾病，

along with psychological and social implications.

同時也牽涉心理與社會層面的影響。

It's not simply a weakness that somebody should get over 片語動詞

它不只是某種需要當事人自己克服的軟弱，

or even something that we have a say in. 慣用語

更不是我們能夠左右的事。

And just like heart disease or cancer,

就像心臟病或癌症一樣，

shedding light onto the subject is of the utmost importance in order to bring funding and proper research. 講解

讓這個議題受到更多關注至關重要，這樣才能爭取經費並進行適當的研究。

But is depression only a human phenomenon?

但憂鬱症是人類獨有的現象嗎？

We look into the question do dogs get depressed in our latest ASAP Thought video 片語動詞

在最新的 ASAP Thought 影片中，我們探討了「狗會不會憂鬱」這個問題，

and discover the many studies done to understand depression among other species,

並了解為了研究其他物種的憂鬱症而進行的眾多研究，

including your pets at home.

其中也包括你家裡的寵物。

You can click the link in the description for that video.

你可以點擊說明欄中的連結觀看該影片。

You can also check out the book Animal Madness by Laurel Braitman,

你也可以看看 Laurel Braitman 所著的《Animal Madness》，

which touches on the subject.

書中也談到了這個主題。

In fact, you can get it for free from our friends at Audible by going to audible.com/asap.

事實上，只要前往 audible.com/asap，就能從我們的朋友 Audible 那裡免費取得這本書。

Audible is the leading provider of audiobooks with over 150,000 downloadable titles across all types of literature.

Audible 是領先的有聲書供應商，擁有超過15萬部可下載作品，涵蓋各類文學。

You can download this audiobook or another of your choice for free at audible.com/asap.

你可以在 audible.com/asap 免費下載這本有聲書，或任選另一本。

And with a subscription, you get one free book a month.

訂閱後，你每個月還能免費獲得一本書。

Special thanks to Audible for making these videos possible.

特別感謝 Audible 的支持，讓這些影片得以製作。

If you think you're suffering from depression, we've included some resources and more information in the description. 片語搭配

如果你覺得自己可能罹患憂鬱症，我們在說明欄中提供了一些資源和更多資訊。

And subscribe for more weekly science videos.

記得訂閱，觀看每週更新的更多科學影片。