The answer lies not in the heart, but in the brain.

答案不在心臟，而在大腦。

When you find someone attractive, the brain is flooded with dopamine and noradrenaline, which make you feel elated and alert.

當你發現某人很有魅力時，大腦中就會充斥著多巴胺和去甲腎上腺素，它們會讓你感到興奮和警覺。

Research shows that this can happen within a fraction of a second.

研究表明，這種情況可能在幾分之一秒內發生。

These chemicals appear to shut down some areas of the brain, like the prefrontal cortex, which regulates self-awareness and rational behavior.

這些化學物質似乎會關閉大腦的某些區域，如調節自我意識和理性行為的前額葉皮層。

The rush of dopamine activates the reward circuitry of the brain, the same areas that are active when humans feel a rush from cocaine.

多巴胺的衝動激活了大腦的獎賞迴路，與人類從古柯鹼中獲得快感時活躍的區域相同。

In fact, the behavior associated with passionate love has a lot in common with addiction.

事實上，與熱戀有關的行為與成癮有很多共同之處。

At the same time, the brain experiences a drop in serotonin, a chemical that regulates mood, which scientists believe causes behavior resembling that seen in people with anxiety and obsessive-compulsive disorder.

與此同時，大腦中的血清素（一種調節情緒的化學物質）也會下降，科學家認為這會導致類似焦慮症和強迫症患者的行為。

The intense feeling of passion at the start of a relationship often gives way to a more calm attachment.

戀愛初期的強烈激情往往會讓位給更加平靜的依戀。

The hypothalamus releases oxytocin and vasopressin into the reward system of the brain, which spark feelings of bonding and arousal.

下丘腦會向大腦的獎勵系統釋放催產素和血管加壓素，從而激發親情和喚醒感。

One theory is that the intensity of love is, in fact, the brain tricking couples into bonding for the difficult task of raising children. What's more, one study suggests that the brain treats love as essential to human survival.

有一種理論認為，強烈的愛其實是大腦在欺騙夫妻，讓他們為撫養孩子的艱鉅任務而結合在一起。更有甚者，一項研究表明，大腦將愛情視為人類生存的必要條件。

When participants looked at an image of their romantic partner, the part of the brain associated with fulfilling basic needs, like eating or drinking, lit up, suggesting that love, much like hunger and thirst, is vital to the continuation of our species.

當參與者看到浪漫伴侶的影像時，大腦中與滿足基本需求（如吃喝）相關的部分就會亮起來，這表明愛情就像飢餓和口渴一樣，對我們人類的延續至關重要。