Placeholder Image

字幕表 動画を再生する

  • Whether it is during a sad movie you swore you would never tear up in, or a heart-wrenching

  • break-up following your first love, crying may seem like a strange physical

  • response to your emotional turmoil. Why do we start the waterworks when we feel

  • really sad? Is there a biological advantage or purpose other than washing

  • your face or streaking your mascara? Well crying does not only happen when you are

  • emotional, there are actually three types of tears. Basal tears are perpetually

  • lubricating your eyes keeping them from drying out, while reflex tears act in

  • response to an irritant like onions or dust.

  • They begin a chain reaction releasing hormones from the brain which then

  • trigger a tear response from the glands in the eyelids. And these tears help to get rid

  • of the irritant.

  • But tears of sadness? Strangely this leaky face phenomenon is exclusive to

  • humans with a couple different theories as to why. And one is strikingly similar

  • to the reason we blush, which we described in a previous video here. In

  • many cases emotional tears are able to act as a signal to others of our

  • genuine sadness or distress. That is not always easy to fake. Your tears blur

  • your vision, essentially handicapping any aggressive or defensive actions sending

  • those nearby a signal of need appeasement or attachment.

  • From an evolutionary perspective, this increases communication with those close

  • to you and ultimately your chance of survival.

  • Some experiments have even taken photos of people crying and made copies

  • with the tears digitally removed. Not surprisingly, people rated the pictures

  • with tears to be more sad, while the ones without were often confused with puzzlement,

  • awe or other expressions.

  • But what about tears of joy? Well perhaps they are not so different, afterall tears of

  • happiness may still be used as social signals for how we feel, and are thought to

  • strengthen bonds between people. Also both emotions see activity in similar

  • regions of the brain, such as the hypothalamus and basal ganglia

  • which just happen to be connected to your tear glands.

  • Another theory suggests that crying is one of your body's mechanisms to

  • literally shed your stress. Interestingly reflex tears and emotional tears have

  • very different compositions. Emotional tears have much higher levels of

  • proteins, in particular some called adrenocorticotropic hormones

  • which are linked to high stress levels. And some say crying helps to release these

  • stress chemicals from the body, but the research here is limited and not yet conclusive.

  • So go on,

  • have a good cry,

  • let the world know how you feel and potentially let out that stress.

  • Got a burning question you want answered.

  • Ask it in the comments, or on facebook and twitter. And subscrice for more

  • weekly science videos.

Whether it is during a sad movie you swore you would never tear up in, or a heart-wrenching


動画の操作 ここで「動画」の調整と「字幕」の表示を設定することができます

B1 中級

なぜ私たちは泣くのか? (Why Do We Cry?)

  • 2077 168
    VoiceTube に公開 2021 年 01 月 14 日