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What causes the heart to beat fast when a person is frightened?

Answer 1

Increased secretion of adrenaline hormone

The fight-or-flight response basically causes the adrenal glands near the kidneys to secrete more adrenaline hormone, which has a number of physiological effects that help the person fight off the perceived threat or danger, such as sweating, dilated pupils, and an increased heartbeat that raises blood pressure and increases oxygen availability to the cells and muscles.

(However, if this happens too frequently, as in the case of prolonged stress, it may negatively impact the body and result in chronic illness).

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Answer 2

Mason Anderson

When a person is frightened, the body releases adrenaline, which increases heart rate by stimulating the heart to beat faster. This is part of the body's fight-or-flight response to perceived danger.

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Answer from HIX Tutor

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