The three types of nervous system are: Central nervous system (CNS): The CNS, which comprises the brain and spinal cord, carries out the tasks of processing and combining information. Peripheral nervous system (PNS): Consists of all the nerves outside the CNS and is responsible for transmitting signals between the CNS and the rest of the body. Autonomic nervous system (ANS): A division of the PNS that regulates involuntary bodily functions such as heart rate, digestion, and breathing. The autonomic nervous system (ANS) can be classified into two separate systems, namely the sympathetic nervous system and the parasympathetic nervous system.