autonomic nervous system (ANS) controls involuntary functions and is comprised
of the sympathetic nervous system (SANS) which stimulates organs for fight or
flight actions and the parasympathetic autonomic nervous system (PANS) which
slows down bodily processes for rest and digesting.
component of the SANS and PANS are the same but differ in their physical
structure. Signals released by either one have to cross two synapses in order
to reach their desired effector. The neurons travel from root in the spinal
cord down axons to the synapse within the ganglia where it is then redirected
to the effector organ where it synapses again to create the signalled response.
The difference between the two systems is that they originate at different sights
the SANS can be found in the thoracolumbar area where a network of nerves
radiates from the spine whereas the PANS is located at the craniosacral.
ganglia of the SANS trigger action potentials to other neurons in turn
signalling messages to multiple effectors, the preganglionic cell fibres are
also shorter than their post ganglionic enabling the signals to reach further.
The ganglia of the PANS however is located nearer to the organs that it is
serving and extend from cranium and
sacrum, their preganglionic cell fibres are therefore longer than their post
ganglionic enabling them to specific strategic signals at time of rest when
energy is available.
SANS is a vital
system needed when faced with fight or flight scenarios but the same physiological
responses can be released in situations of non-immediate stress. When your body
exhibits stress two chemicals could be released and the substance effect is
variable on the location where it is received. The chemicals are released via neurotransmitters
as part of the nervous system and are created then released from the neurons
themselves to communicate with the effector organ across a synapse, or through
hormones as part of the endocrine system and are secreted though glands and