What causes the 'fight or flight' response to subside after the perceived threat has passed?

💡 Explanation

The 'fight or flight' response decreases due to enzymatic degradation of neurotransmitters in the synapse because enzymes like acetylcholinesterase break down acetylcholine and other neurotransmitters; therefore, the stimulation of the postsynaptic neuron diminishes, rather than continuing indefinitely due to constant receptor activation.

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