For centuries, humans have been using substances to alter their state of mind, from caffeine, cigarettes and alcohol, to more extreme drugs. But as the most commonly used illicit drug in North America, where does marijuana fit in? And how exactly does it affect your brain?
幾世紀以來，人類一直使用物質去調整心情，從咖啡因、香菸和酒精，到更極端的藥物。但身為北美最常使用的禁藥，大麻到底佔有什麼樣的地位？還有它實際上是如何影響你的腦袋的？
First, we need to understand how the brain functions. Your neurons are the cells that process information in the brain, by releasing chemicals called Neuro-Transmitters from the axon of one neuron to the dendrite of another. They change the electrical charge of the receiving neuron, consequently exciting or inhibiting it. If excited, the signal is passed on.
首先，我們得了解大腦如何運作。你的「神經元」是大腦中處理資訊的細胞，藉由從神經元的軸突釋放叫做神經傳遞質的化學物質到另一個神經元的樹狀棘突來處理資訊。它們改變接收資訊神經元的電荷，因而刺激或是抑制神經元。如果遭受刺激，這訊號就被傳遞下去。
Though it sounds simple, these signals work together, and the effect is quickly compounded into complex configurations within milliseconds, flushing over the entire brain. This is what happens every single time you think, breath, or move.
雖然聽起來簡單，這些訊號一起運作，其效果是在數毫秒內快速的複合成複雜的結構，奔流在整個大腦中。這就是每當你思考、呼吸或是移動所發生的事情。
So what is going on inside your brain when you are smoking marijuana? Well, unlike alcohol, which contains molecules nothing like those in our body, Cannibis contains molecules that resemble those produced in our very own brains: Cannabinoids. Though, naturally these cannabinoids circulate in much lower quantities compared to the large influx imposed by smoking.
所以當你抽大麻的時候，腦袋裡發生什麼事？這個嘛，不像是酒精，含有一點也不像我們體內所擁有的分子結構，「大麻煙」含有一些分子就類似是我們自己大腦所製造的東西：「大麻醇」。然而，自然地，和抽大麻所帶來的大量注入相比，這些大麻醇是以低很多的量在體內循環。
Specifically the chemical Tetrahydrocannabinol, or THC, resembles a natural transmitter called Anandamide. These cannabinoids are specialized neurotransmitters released by neurons having just fired. Neurons temporarily become unresponsive after firing, to prevent them from overreacting or being too dominant. This allows your brain to function in a calm and controlled manner.
特別地，化學物質「四氫大麻醇(或THC)」很像是一種叫做「內生性大麻素」的天然傳遞質。這些大麻醇是由剛發射過的神經元釋出的特殊神經傳遞質。神經元在發射過後暫時變成無反應狀態，以防止它們反應過度或強勢反應。這讓你的大腦以一個冷靜且受控制的方式運作。
But cannabinoids interrupt this approach in some parts of the brain. Instead, they remove the refractory period of neurons that are already active and cause your thoughts, imagination and perception to utterly magnify itself.
但大麻醇在大腦中的某些部位打斷了這步驟。他們反而移除了神經元已經啟動的「乏興奮期」並造成你的思考、想像和感知能力完全的自我擴大。
This means once you begin your train of thought, it becomes the most significant and profound thing ever. You can't see the big picture or even recall your last epiphany, because you are caught up in the momentum of a particular idea, and your neurons keep firing. Until a new idea takes hold, and you go off on a new tangent.
這意味著一旦你開始你的思路，它會變成有史以來最意義重大且深邃的東西。你無法看到全面，或甚至無法回憶上一個畫面，因為你被一個特殊思緒的氣勢給綁死了，然後你的神經元不斷地發射訊號。直到一個新點子佔據主導地位，你才會突然轉換到另一新思路上。
These cannabinoids also affect the levels of dopamine and norepinephrine in your brain, often leading to a sense of euphoria, relaxation, pain modulation and general enhancement of an experience, though sometimes causing anxiety. Furthermore, there are cannabinoid receptors in areas controlling short term memory, learning, coordination, movement control and higher cognitive functions.
這些大麻醇同時影響你大腦中多巴胺和正腎上腺素的多寡，通常導致陶醉、放鬆、疼痛感的調變和一般感受的加強，雖然有時候會引起焦慮。此外，在控制短期記憶、學習、協調、運動控制和更高等的認知功能的區域都有大麻醇受體。
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