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The cell bodies of large myelinated axons reside in the grey matter of the spinal cord in the anterior horn. They send their axons out of the ventral root and either directly into peripheral nerves, or nerve plexuses (a branching network of intersecting nerves) which give rise to peripheral nerves.

The autonomic nervous system regulates involuntary bodily functions through two complementary divisions: the sympathetic nervous system and the parasympathetic nervous system.

The cell bodies of efferent pathways (motor and autonomic) lie in the spinal cord of the central nervous system (CNS) and peripheral nerves contain axons from these neuronal cell bodies as well as those situated in peripheral ganglia.

Receptors are crucial for transducing chemical, mechanical, thermal or light stimuli into signals that the rest of the nervous system will understand.

The receptive field of a neuron usually coincides with its perceptive field – the area from which a sensation is perceived to arise. The overlapping of receptive fields of individual neurons allows for perception to smoothly move from one sensory neuron to the next.

Slowly adapting receptors’ respond to prolonged and constant stimulation, and generate action potentials throughout the entire stimulation period; ‘rapidly adapting receptors’ fire only at the beginning and at the end of a stimulus, and stop firing in response to stimulation whose frequency does not change.