Answer:
Autonomic nervous system.
Step-by-step explanation:
The human psychology involves the study of the emotions, anger and feelings of the humans with themselves and other people of the society. The emotions are controlled by the external as well as internal factors.
The peripheral nervous system of the body constitutes the autonomic nervous system. This system is activated during the stress and anxiety response. The autonomic nervous system prepares the body for the fight and flight mechanism.
Thus, the answer is autonomic nervous system.