One nice day you’re walking along a wooded path. You come around a corner and there, coiled in the path, is a huge rattlesnake, its rattles abuzz. You are deathly afraid of snakes.
Various parts of the brain signal the nervous systems and organs to prepare to take action. The pupils of the eyes dilate, the thyroid gland raises the resting metabolic rate. The bronchioles in the lungs dilate to admit more oxygen, hairs stand on end. Heart rate and blood pressure rise to supply the body and brain with fuel.
The liver begins to break down sugars for quick energy, blood vessels in the skin contract causing chills and sweating. The spleen pumps out white blood cells in case there is an injury. Stomach and intestine enzyme secretion and muscle activity needed for digestion stop, and blood vessels in the stomach and intestines contract to divert blood to the muscles.
The bladder and colon prepare to empty, the central portion of the adrenal medulla floods the bloodstream with adrenaline and noradrenaline, constricting the blood vessels, breathing quickens. The entire body is in a state of high alert, ready to stay and fight or say “Feet don’t fail me now.”
Did you follow all that? Of course not, but all that, and more, happens in your body within seconds of your sensing a threat.
It makes us tired just to think about it!
天氣不錯(cuò)的一天,你漫步在林蔭小道。走到小道拐角一處,你突然發(fā)現(xiàn)一條巨大的響尾蛇就蜷縮在那!它還嘶嘶地吐著蛇信。你可是怕蛇怕得要死。
多個(gè)大腦部位傳送出采取措施的信號(hào)給神經(jīng)系統(tǒng)和各個(gè)器官:瞳孔放大,甲狀腺加快新陳代謝,肺部的支氣管擴(kuò)張吸進(jìn)更多氧氣,毛骨悚然,心率加快,血壓上升以便供給身體和大腦能量。
肝臟加速分解糖分供能。皮下血管收縮,身體發(fā)冷出汗。脾臟產(chǎn)生更多白細(xì)胞抵抗受傷。腸胃酶的分泌及肌肉活動(dòng)引起食欲不振。腸胃的血管收縮,血液傳輸?shù)郊∪饨M織。
大小便可能失禁哦。血液隨腎上腺素和去甲腎上腺素匯聚到腎上腺髓質(zhì)的中部,血管收縮,呼吸加快。整個(gè)人都處于高度戒備,要么呆在那不動(dòng),或者人蛇大戰(zhàn),再或者告訴自己“我一點(diǎn)都不怕”。
受到驚嚇,身體會(huì)做出上述所有反應(yīng)嗎?當(dāng)然不是所有咯!但是,當(dāng)你遭遇驚嚇,身體會(huì)在僅僅幾秒內(nèi)產(chǎn)生更多反應(yīng)。
光是想想就怪累人的!