The nervous system has two major divisions, the and the .

The central nervous system consists of and .

The four principle parts of neurons are: , , and .

The role of dendrites is to from or from a .

The of a neuron integrates the information received by dendrites, and decides whether or not to send information of its own.

of a neuron send the neuron's signals to other neurons.

The of a neuron carries the neuron's output information.

Information from one neuron is transmitted to another neuron at .

The membrane potential at a given time is determined by the across the .

An action potential is a brief change in .

During an action potential, the opening of permits an , which eventually returns the membrane potential to its resting value.

During an action potential, the opening of permits an , which depolarizes the neuron.

At terminal buttons, contain , which serve as chemical signals for communication between neurons.

The neurotransmitter molecules released into a synaptic cleft can open up ion channels on the postsynaptic membrane, which permits across the postsynaptic membrane.

After ion channels are opened up y neurotransmitter molecules, the flow of ions across the postsynaptic membrane could either have an effect, which makes the postsynaptic neuron more likely to fire, or have an effect, which makes the postsynaptic neuron less likely to fire.

or refers to the direction toward the front of the brain.

or refers to the top of the brain.

or refers to the bottom of the brain.

or refers to the back of the brain.

means toward the centre of the brain, away from the side.

means toward the side of the brain, away from the centre.

The brain has three major divisions: the , the , and the .

The cerebral hemispheres are covered by the , which is greatly convoluted.

The grey matter mainly consists of , whereas the white matter mainly consists of .

The lateral surface of the cerebral cortex is divided into four lobes, , , , and lobes.

The lobe is ventral to the frontal lobe and the parietal lobe.

The lobe is caudal to the parietal and the temporal lobe.

The limbic system includes the (or ), the , and the .

The of the forebrain and the of the hindbrain both play important roles in the control of movement.

The relays all sensory information (except smell) from sensory organs to the cerebral cortex.

The is the main interface between the brain and the hormonal systems of the body.

The of the hindbrain relays information from the cerebral cortex to the cerebellum.

The is the most caudal portion of the brain stem, which regulates vital functions such as breathing and heart rate.