There are two types of cells responsible for myelinating axons in the nervous system: oligodendrocytes and Schwann cells. They only differ by the division of the nervous system in which they are found. Oligodendrocytes myelinate axons in the central nervous system, while Schwann cells myelinate axons in the peripheral nervous system.

Ependymal cells and astrocytes are other types of neuroglia. Ependymal cells secrete cerebrospinal fluid (CSF) into the central nervous system. Astrocytes play a key role in creating the blood-brain barrier in the central nervous system.

The cerebrum is the portion of the brain above the middle of the brain, or diencephalon. The thalamus is a part of the diencephalon, and it is intimately associated with motor behaviors, such as walking or flying (in birds). The cerebrum is divides into four lobes based on location and function. The frontal lobe contains the motor cortex and pre-frontal cortex, as well as Broca's area. It is associated with thought and higher brain function. The parietal lobe contains the sensory cortex and processes tactile input. The temporal lobe contains the hippocampus and auditory cortex. The occipital lobe contains the visual cortex.

Nervous tissue contains a variety of support cells in order to preserve the neurons in the brain, known as glial cells. Microglia are similar to monocytes, a type of white blood cell. They are used to remove debris and pathogens from the central nervous system.

Schwann cells, oligodendrocytes, and astrocytes are all part of the neural glia. Schwann cells produce myelin around the axons of neurons in the peripheral nervous system, while oligodendrocytes produce myelin for the axons of neurons in the central nervous system. Astrocytes around found in the central nervous system and help create the blood-brain barrier.

Sensory neurons respond to stimuli, such as pain. Association neurons receive signals from the sensory neurons and, on the basis of that input, activate motor neurons. Motor neurons activate muscles or glands. Effectors are the muscles or glands that perform the response directed by the nervous system.

Connective tissue consists of bone, cartilage, blood, and fat and is not involved in this process. Connective neurons is a misnomer. Interneurons, however, can be used to relay signals between sensory and motor neurons in the spinal cord.

White matter is white due to the myelin sheath. Since the myelin sheath only covers the axon, neural tissue that is referred to as white matter is only located on a neuron's axon. Grey matter actually refers to the cell body due to its grayish appearance. Accordingly, one neuron is actually part of both the white and the gray matter in the nervous system.