Why does my heart beat so fast?

Why does your heart beat fast when you are scared?

• Answer:

  When something frightens you(blanket term for frightening or stressful things being a "stressor"), your body reacts to the stressor to prepare your body to fight or run away from the problem. This is where the term Fight or Flight comes from. The hypothalamus sends an electrical impulse down your nerves to your adrenal glands, which sit on top of your kidneys. These produce adrenaline and send it into your bloodstream. Adrenaline can cause: your breathing to speed up; your pupils to dilate; saliva production to slow down or stop; blood to drain away from non-critical organs like skin and stomach; decreased sensitivity to pain; and your heart rate to speed up. This is an evolved process to help us escape or neutralise dangerous situations.