The human brain is the main part of
CNS
The central nervous system (CNS) controls most functions of the body and mind. It consists of two parts: the brain and the spinal cord. The brain is the centre of our thoughts, the interpreter of our external environment, and the origin of control over body movement. The peripheral nervous system (PNS) consists of the nerves and ganglia outside the brain and spinal cord. The autonomic nervous system (ANS) is a control system that acts largely unconsciously and regulates bodily functions such as the heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal.