Doctor 1: So, how did it get to be this way?
(殭屍聲) 博士 1:它到底為什麼會這樣子呢?
Doctor 2: Well, it’s my professional opinion that the large gaping bite mark on its shoulder might have something to do with it.
博士 2:根據我專業的判斷: 這應該和它肩膀上那個被咬到的傷口有關。
D1: Thanks. I mean, what causes its behavioral abnormalities?
博士 1:真是謝謝啊! 我是說什麼造成它的行為異常呢?
D2: Well, we know all behaviors are rooted in the brain, so I’d expect that something’s gone terribly wrong, probably in there.
博士 2:嗯,我們都知道行為由大腦控制, 所以我猜測它應該是腦袋壞了。
D1: Thanks again, Doctor Obvious. Let me be more specific. What changes in the brain would have to occur in order to cause this kind of behavior?
博士1:謝謝你指出 這個顯而易見的事實。 讓我說得更精確些吧! 到怎麼樣的腦部病變 會造成這種行為的改變?
D2: Hmm. Well, let's see. The first thing I notice is how it moves. Stiff legged, with long, lumbering steps, very slow and awkward. Almost like what you’d see in Parkinson’s disease. Maybe something’s wrong with his basal ganglia? Those are a collection of deep brain regions that regulate movement, through a neurochemical called dopamine. Although most people think of dopamine as the “happy” chemical of the brain, the dopamine-containing neurons in the basal ganglia die off in Parkinson’s disease— that’s what causes it. Makes it more and more difficult to initiate actions.
博士2:嗯…噢…讓我們看看…… 首先我注意到它的行動方式。 僵硬的腳、延長而沈重的步伐, 非常的緩慢和怪異。 這就像你會在帕金森氏症上所看到的病徵。 (帕金森氏症:一種因為製造多巴胺腦細胞壞死所造成的神經退化性疾病,好發於50歲以上的人) 或許是它的基底核出了問題? 基底核位於大腦深處, 藉由釋放一種叫多巴胺的 神經傳導物質來控制行動。 (譯注:神經傳導物質用於神經元間的訊號傳導) 雖然多巴胺常被想像成腦中的「快樂因子」, (譯注:因為多巴胺也負責傳遞愉快、興奮等情緒的訊息) 但在帕金森氏症中,基底核內負責釋放多巴胺的神經元壞死 (多巴胺在腦中作為神經傳導物質,也是腎上腺素的前驅物) 造成行為的異常。 這讓他要開始行動時更加困難。
D1: What? Look again at how it moves. Stiff legs, long stance. These aren’t Parkinsonian movements; Parkinson’s patients take short, shuffling steps. And the posture’s all wrong. This looks to me like what happens when the cerebellum is damaged. The cerebellum’s a little cauliflower shaped area in the back of your head, but don’t let its size fool you. That little guy contains almost half of the neurons in the entire brain. Patients who suffer degeneration from this region, something called spino-cerebellar ataxia, show a lack of coordination that results in stiff legs, wide stance, and a lumbering walk. My money's on the cerebellum.
博士 1:你說啥? 你再仔細看看他的行動方式: 僵硬的腳、筆直的站姿, 這和帕金森氏症病患的行動方式不符: 帕金森氏病患步程短且會拖著腳走。 而且這站姿也完全不符。 我覺得這看起來像是小腦損傷所造成的狀況。 小腦就是在你後腦勺內 一小塊像是花椰菜的區域, 但別被外表所矇騙, 大半腦中的神經元都集中在這小小的區域。 有些在這部份退化的病患 (運動失調症:肌肉失調和不規則顫動) —─或稱為脊髓小腦運動失調症—─ 會失去平衡感而造成僵直腿部、 寬鬆站姿和拖腳行走的狀況。 我打賭是小腦有問題。
D2: Touché. OK. So we’ve nailed its motor problems. Now what about that whole groaning, lack of talking thing?
博士 2:得分。好,我們已經知道它行為上問題。 那怎麼解釋它不斷的呻吟和無法言語呢?
D1: Hmm. You know, it sounds kind of like expressive aphasia, or Broca’s aphasia, which makes producing words difficult. This is caused by damage to the inferior frontal gyrus, or possibly the anterior insula, both regions behind your temple on the left side of your head.
博士 1:嗯,你知道嗎,這聽起來像是表達型失語症, 或又稱為布洛克失語症, 這種病造成運用文字表達的困難。 (表達型失語症是因大腦損傷導說、寫能力受損。) 這可能和額葉額下回受損有關, (譯注:額葉額下回即布洛克區,該區負責語言表達) 或者也有可能是前腦島, 這兩個區域就在左半邊腦部、太陽穴的下方。
D2: I think you’re only half right. Zombies definitely can’t communicate, that’s for sure. But they don’t seem to do a good job of understanding things either. Watch this. Hey, Walker! Your father smelt of elderberries! See? No reaction. Either it’s not a Monty Python fan, or it can’t understand me. I’d say this is like spot-on fluent Wernicke’s aphasia: damage to an area at the junction of two of the brain’s lobes, temporal and parietal, typically on the left side of the brain, is the culprit. This area is physically connected to Broca’s area, that you mentioned, by a massive bundle of neurofibers called the arcuate fasciculus. I hypothesize that this massive bundle of connections is completely wiped out in a zombie. It would be like taking out the superhighway between two cities. One city that manufactures a product, and the other that ships it out to the rest of the world. Without that highway, the product distribution just shuts down.
博士 2:我覺得你只答對了一半。 殭屍確實沒辦法清楚表達。 但是它們對於理解事物的能力也很差。 (譯注:這是回應博士 1 對於殭屍患有布洛克失語症的假設,布洛克失語症病人仍保有理解語言的能力。) 看我的!嘿!你爸臭死了! (大笑)看吧!沒有反應。 它要不是蒙蒂蟒蛇的粉絲,就是它聽不懂我說的話。 (譯注:博士 2 喊話原文出自蒙蒂蟒蛇演出的聖杯傳奇) 我認為這應該是魏尼克失語症, (其症患者會講出流利卻無意義的文字,並有聽、讀障礙) 在大腦頂葉和聶葉兩葉的連接處、 尤其是在大腦左側的傷害就是病因。 這部份也藉由一大束 被稱為神經纖維束的神經纖維 連接到你提及的布洛克區。 我假設這一大叢連接束在殭屍中完全損壞了。 這神經纖維束就像兩城市間的高速公路。 其中一座城市負責生產產品, 而另一座城市負責出口到世界各地。 如果沒有高速公路,產品就不能出口。
D1: So, basically it’s a moot point to reason with a zombie, since they can’t understand you, let alone talk back.
博士 1:所以這就是假設造成殭屍的原因, 既然它們沒辦法聽懂你說的話,更別提反駁了。
D2: I mean, you could try, man, but I’m going to stay on this side of the glass.
博士 2:(大笑)我是說你試著進去和它說說看啊, 不過我想我待在這裡比較安全。