Presentation on theme: "Anatomically The whole nervous system can be anatomically divided into: * Central nervous system. * Peripheral nervous system. Physiological organization."— Presentation transcript:
anatomically The whole nervous system can be anatomically divided into: * Central nervous system. * Peripheral nervous system. Physiological organization Physiological organization of the nervous system are: * Somatic nervous system mainly deals with the voluntary and conscious aspects of neurological control. * The autonomic nervous system (ANS): deals with involuntary control mechanisms.
Divisions of the autonomic nervous system * SYMPATHETIC: thoracolumbar outflow, catabolic in function * PARASYMPATHETIC: craniosacral outflow, anabolic in function Cranial nerves, i.e. Cr III, VII, IX & X. 2 nd, 3 rd and 4 th sacral segments
Autonomic ganglia Definition: A ganglion is a collection of nerve cells out side the CNS. Types: Three types: Lateral: site for relay of sympathetic nerves. Collateral: It is site for relay of both sympathetic and parasympathetic nerves. Terminal: site of relay for parasympathetic nerves.
Function of autonomic ganglia: RRelay stations. RRelease of chemical transmittion DDistributing function. Regeneration of post ganglionoic fibers.
Origin and distribution of sympathetic nervous system
General functions of the sympathetic nervous system: (The alarm response or stress response) In emergency conditions: e.g. in cases of fight, flight, muscular exercise, emotions, pain and cold, generalized sympathetic excitement occurs (the alarm response or stress response): Acceleration of the heart. Dilatation of bronchi. Vasoconstriction in inactive regions.
Sweat secretion. Delay muscle fatigue. Contraction of spleen. Glycogenolysis. Adrenal secretion. All the above reactions prepare the body for fight or flight or to face an emergency situation.
Horner's Syndrome: damage of the superior cervical sympathetic ganglion leads to: Ptosis. Miosis. Anhydrosis. Vasodilatation.
Origin and distributio n of parasympat hetic nervous system
General functions of parasympathetic system: Parasympathetic functions are anabolic and energy preserving Its function becomes most apparent in a person at rest after a meal and reading a newspaper.