Structure and Function of the Nervous System

The nervous system is made up of two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS).
The CNS includes the brain and spinal cord. It processes information and decides how to respond.
The PNS, which consists of the nerves outside of the brain and spinal cord, transmits messages between the CNS and the rest of the body.
The nervous system uses neurons, or nerve cells, to transmit information. Each neuron consists of a cell body, axon and dendrites.
Signals travel from the dendrites, through the cell body and down the axon to reach other neurons.
The point at which one neuron meets another is called a synapse. Information is transmitted across synapses via chemical messengers known as neurotransmitters.
The nervous system works with the endocrine system to regulate behaviour and maintain homeostasis.
There are two main types of nerve in the PNS: sensory nerves, which carry messages to the CNS, and motor nerves, which carry messages from the CNS to the muscles and glands.
The PNS also includes the autonomic nervous system (ANS), which controls involuntary processes like heartbeat and digestion. The ANS is divided into two branches: the sympathetic nervous system, which prepares the body for action, and the parasympathetic nervous system, which calms the body down.
The brain has numerous parts, each with specific functions. For example, the frontal lobe is responsible for reasoning and decision making, while the temporal lobe deals with memory and hearing.
Understanding the structure and function of the nervous system is vital to understanding individual and social behaviour. For instance, damage to specific parts of the brain can alter personality, perception and communication.