Human body and it's mechanisms, especially those related to brain such as emotions are very complex and single word answers doesn't do justice..
So the answer to ur question is quite complex, however, a chemical imbalance between Neurotransmitters like Serotonin, dopamine, norepinephrine etc within the brain pathways causes emotional reactions akin to fear, sadness etc..
Answered2022-03-17 07:19:14
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