Neurons are classified functionally according to the direction the travels relative to the . Afferent neurons are the neurons of the sensory nervous system. They are responsible for conducting input from both somatic sensory and visceral sensory receptors. Most sensory neurons are . Efferent neurons are the neurons of the motor nervous system, conducting output from the CNS to the effectors. All motor neurons are . Interneurons (or neurons) lie entirely within the CNS. They receive stimulation from many other neurons and carry out the integrative function of the nervous system. The most numerous types of neurons are .