!Nerves and Nerve Systems
!!Anatomy
Nerves receive and transmit __electric impulses for steering__ and coordination of vital functions.
They pervade the whole body as a tree with branches, whose stem is situated in the ((Nervous - Brain|brain)) and spinal cord.
Nerves consist of several fibres (__neurons__), each with a cell body (__soma__), nucleus, __dendrites__ for stimuli reception and an __axon__ for transmission. The axons of most nerves possess a __((Nervous - Myelin Sheath|myelin sheath))__ of glia cells. At the end of an axon, the contact to other nerve cells or tissues is made by __synapses__, as in the myoneural junctions in ((Musculoskeletal - Skeletal Muscles|muscle fibres)).

The bridge between nerve- and ((Endocrine - System Overview|homonal systems)) are the __hypothalamus__ and ((Endocrine - Pituitary Gland - Anterior Lobe|pituitary)) in the brain.

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!!Nerve systems
By function and mode of operation, we distinguish:

1. The __Autonomous Nerve System__ (ANS) which steers the involuntary rhythms, reactions and adaptions of the organs. It is divided into
*the activating __sympathetic__ nerve system, whose impulses enable fight or flight responses 
*the inhibiting __parasympathetic__ nerve sysem, that dominates in relaxation and regeneration but also in freeze reflexes (UDIN).
*the __enteric__ nerve sysem or "gut brain" of the intestinal tract, which is influenced by the sympathetic and parasympathetic branches.
The Autonomous Nerve System effects our wake and sleep cycles, activity, rest and regeneration. The __META-Health Phases Model__ is largely based upon the responses of the Autonomous Nervous System.
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2. The somatic or __cerebrospinal nerve system __guides the perception of external stimuli (the sensory input) and the voluntary functions (the motoric output). By location we distinguish
*the __central nerve system__ (CNS) consisting of brain and spinal cord
*the __peripheral nerve system__ begins where the nerves leave the spinal canal.

__Afferent__ neural pathways (leading towards the brain) transmit sensory perceptions for processing, while __efferent__ pathways run from the brain towards effecting organs, like the motoric nerves run to muscles.

!!META-Organ Tissues:
__((Nervous - Brain|Brain Overview))__

__((Nervous - Brain - Meninges|Brain - Meninges)) __(CB +/- and CC-/+): Protection of Brain and Beliefs 

__((Nervous - Myelin Sheath|Myelin Sheath))__ of nerves (CB +/-): Fear of Contact, Fear of Pain

__((Nervous - Sensory Innervation|Sensory Innervation))__ (CC -/+): not wanting, being able, or allowed to Feel / Perceive

__((Nervous - Motoric Innervation|Motoric Innervation))__ (CC -/+): Paralyzing Trauma or Physical Overload

Details of __((Nervous - Facial Nerve|Facial Nerve))__ 

Details of __((Nervous - Trigeminus|Trigeminus Nerve))__