<P> There are inhibitory and excitatory synapses between neurons . Relatively recently, a third subsystem of neurons that have been named non-noradrenergic, non-cholinergic transmitters (because they use nitric oxide as a neurotransmitter) have been described and found to be integral in autonomic function, in particular in the gut and the lungs . </P> <P> Although the ANS is also known as the visceral nervous system, the ANS is only connected with the motor side . Most autonomous functions are involuntary but they can often work in conjunction with the somatic nervous system which provides voluntary control . </P> <P> The autonomic nervous system is divided into the sympathetic nervous system and parasympathetic nervous system . The sympathetic division emerges from the spinal cord in the thoracic and lumbar areas, terminating around L2 - 3 . The parasympathetic division has craniosacral "outflow", meaning that the neurons begin at the cranial nerves (specifically the oculomotor nerve, facial nerve, glossopharyngeal nerve and vagus nerve) and sacral (S2 - S4) spinal cord . </P> <P> The autonomic nervous system is unique in that it requires a sequential two - neuron efferent pathway; the preganglionic neuron must first synapse onto a postganglionic neuron before innervating the target organ . The preganglionic, or first, neuron will begin at the "outflow" and will synapse at the postganglionic, or second, neuron's cell body . The postganglionic neuron will then synapse at the target organ . </P>

Where does the autonomic nervous system connect to the central nervous system