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Central regulation of autonomic body functions. Author ass.prof. N.M. Volkova. Autonomic control areas in the brain stem and hypothalamus. Influence of Higher Parts of the Brain on Autonomic Functions. Structures of the limbic system. Autonomic Nervous System. 2 divisions: Sympathetic
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Central regulation of autonomic body functions Author ass.prof. N.M. Volkova
Influence of Higher Parts of the Brain on Autonomic Functions
Autonomic Nervous System • 2 divisions: • Sympathetic • “Fight or flight” • “E” division • Exercise, excitement, emergency, and embarrassment • Parasympathetic • “Rest and digest” • “D” division • Digestion, defecation, and diuresis
The Biological Clock • A tiny sliver of brain tissue, less than the size of a pinhead, regulates the timing of our bodies. Within this sliver lies a biological clock that keeps track of the time of day, and seasons of the year, and marches our bodies and brains in step. • The small cluster of nerve cells that forms the biological clock is called the suprachiasmatic nucleus (SCN). Its name derives from the location of the SCN, just above where the broad optic nerve trunks cross over each other (a site known as the "optic chiasm") on their way back from the eyes to the visual center of the brain. • The SCN also receives information about light and dark from the eyes, but it has its own dedicated pathway of nerves, the retino-hypothalamic tract (RHT), which is separate from the main nerve bundles carrying visual information to the brain.
THE STRESS REACTION • When stress occurs, the sympatheticnervous system is triggered.Norepinephrine isreleased by nerves, and epinephrineis secreted by theadrenal glands. By activatingreceptors in blood vessels andother structures, these substancesready the heart andworking muscles for action.