Mechanism, which triggers trembling when frightened or any emotional stress, different from that, that makes a person shiver in the cold.

When scared, the brain (or rather, part of the brain, called the hypothalamus) sends an alarm to the adrenal glands. In response, they release special substances into the blood – hormones adrenaline and cortisone (they are even called “stress hormones”). The purpose of the production of these hormones – quickly mobilize the body, prepare him for the upcoming physical activity – escape, defense or attack. They cause increased blood pressure, increased heart rate, increased sweating and – Here we come to the answer to the question posed – increasing muscle activity to such an extent, that some of the muscles even start to tremble.

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