Humans are not the only animals who have the ability to laugh. Smiling and laughing have been observed in non-human primate species during social play. This type of behavioral response serves as a signal to the group by spreading positive emotions, decreasing stress, and contributing to the cohesiveness of the group.

    Humor-evoked laughter in humans can be divided into these stages. When listening to a joke, the first part of the humor is the punch line, an incongruous ending. Second, your mind begins to problem-solve in order to interpret this incongruity or surprise. Finally, the brain is able to appreciate these steps, which together form humor and evoke a response of laughter.

    The neurotransmitter dopamine (a brain chemical) is responsible for allowing the brain to progress through the stages of humor. Dopamine allows us to feel good when we laugh. Some studies have demonstrated an improvement in health for chronically ill patients when they are exposed to funny stimuli. Thus the old adage “Laughter is the best medicine" probably has a note of truth in it. 

    并不是只有人類能夠笑。在靈長目類的社會活動中可以觀察到它們會微笑和大笑。這樣的行為可以作為一種信號,來對自己的群體傳遞積極的情緒,降低壓力,還有助于增加群體的凝聚力。

    在人類社會中,由幽默引起的笑可以分為三個階段。當聽一個笑話時,幽默的第一部分是一個巧妙的不合常規的結尾。第二,你的頭腦開始為了解釋這個不合常規或者出乎意料而思考。最后,你的大腦能夠欣賞這些過程,這些過程一起構成了幽默并引發了笑。

    神經傳遞介質多巴胺(腦部一種化學物質)在人腦感受幽默的過程中起了作用。當我們笑的時候,多巴胺讓我們感覺心情很好。一些研究已經證實當慢性病病人接觸有趣的刺激物時,他們的健康會有逐步的改善。所以這句諺語“笑是最好的藥物”也許有事實為證。