WHY DOES MY MOUTH OPEN WHEN I’M APPLYING MASCARA?
AMY MILLS, VIA EMAIL
‘Mascara face’, as it’s sometimes called, is thought to be a result of nerves in our brains cross-firing. The two nerves controlling our eyeball and eyelid movements are rooted in a very similar part of the brain to another nerve that controls the opening and closing of our jaw. So, it’s possible that when the two nerves in charge of eye movements are activated, they trigger off the nearby mouth-opening nerve. This is only a theory, though. A simpler explanation is that we’ve learnt that opening our mouths stretches our skin, which helps with applying make-up, so we keep doing it. HB
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