The autonomic nervous system

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Motor Neurons ◽  
Cranial Nerves ◽  
Sweat Glands ◽  
Effector Cells ◽  
Autonomic Nervous ◽  
General Arrangement ◽  
Motor Nerves

A large part of the nervous system is dedicated to the control of the internal viscera and their functions. Much of the activity of these organs is controlled reflexly at the brainstem level, e.g. the cardiovascular and respiratory centres (the vital centres) in the reticular formation of the medulla controlling cardiac and respiratory activity. There are also centres in the cerebrum, notably the hypothalamus in the diencephalon. Somatic and visceral functions are closely integrated at these higher levels; think of the effect that emotional factors or somatic stimulation can have on heart rate, blood pressure, and gastrointestinal activity when we are nervous or are in pain. The nerves involved in these activities are described as visceral sensory or visceral motor nerves because they control visceral function; this distinguishes them from somatic sensory nerves from peripheral receptors and somatic motor nerves controlling voluntary function. Visceral motor neurons innervate smooth muscle and secretory cells of the gastrointestinal and respiratory systems, the smooth and cardiac muscle of the cardiovascular system, the sweat glands and arrector pili muscles of the skin, and the muscles of the ciliary body and iris of the eyeball. In many cases, there is a dual supply from the sympathetic and parasympathetic divisions of the autonomic nervous system. In both divisions of the autonomic nervous system, there is a sequence of two neurons between the CNS and the effector organ which synapse in peripheral autonomic ganglia. The neurons from the CNS to the synapse in the ganglion are the preganglionic neurons and those from the ganglia to the effector organs are the postganglionic neurons. The enteric plexus is a third set of neurons interposed between the post-ganglionic neurons and the effector cells in the gastrointestinal tract. Figure 17.1 compares the general arrangement of the sympathetic and parasympathetic nervous system. The cell bodies of sympathetic visceral preganglionic motor neurons are located in the intermediolateral horns of the thoracic and upper lumbar segments of the spinal cord while those of the parasympathetic visceral preganglionic (secretomotor) neurons are in the nuclei of four of the cranial nerves and the sacral segments of the spinal cord.

Introduction to Neuroanatomy

Neuroanatomy ◽  
2017 ◽  
pp. 1-26
Author(s):  
Adam J Fisch
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Basal Ganglia ◽  
Vertebral Column ◽  
Cranial Nerves ◽  
Neural Tubes ◽  
Autonomic Nervous ◽  
Limbic Systems ◽  
Cognitive Activities

This chapter focuses on learning the origination and organization of the nervous system and how to draw all the various elements that comprise it. Instructions are given for drawing the cerebrum, basal ganglia, thalamus, limbic systems, brainstem, cranial nerves, vertebral column, spinal cord, peripheral nervous system (PNS), autonomic nervous system (ANS), formation of neural plates, and neural tubes. Additionally, the chapter addresses how the elements of the nervous system are related to each other, notes their function, and outlines their respective sensorimotor and cognitive activities.

‘Neurologie: the doctrine of the nerves’

2021 ◽  
pp. 614-662
Author(s):  
Alastair Compston
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Cranial Nerves ◽  
De Anima ◽  
Autonomic Nervous ◽  
Reflex Movement ◽  
Cerebral Localization ◽  
Brain And Spinal Cord ◽  
The Brain

Chapter 16: ‘Neurologie: the doctrine of the nerves: the brain and nervous stock’ summarizes Willis’s treatises in Cerebri anatome, Nervorumque descriptio et usus (1664), De motu musculari (1670) and De anima brutorum (1672). Willis’s coinage of the term ‘neurologie’, intending this as the doctrine of the nerves based on the anatomy of the cranial nerves rather than the study of diseases affecting the brain and nervous stock, is described. The chapter explains why these treatises are additionally important for assigning function to the cerebrum and cerebellum rather than the ventricles; the concept of cerebral localization; the distinction between voluntary and involuntary, or reflex, movement; Willis’s account of the autonomic nervous system; and his ideas on muscular movement. Apart from these innovative contributions, Willis’s description of the arrangement of blood vessels supplying the brain and spinal cord, for which the book is celebrated, is described. The fifteen engraved plates are included. {148 words}

Autonomic Nervous System Dysfunction Following Spinal Cord Injury: Cardiovascular, Cerebrovascular, and Thermoregulatory Effects

2015 ◽  
Vol 3 (3) ◽  
pp. 197-205 ◽  
Author(s):  
Jill M. Wecht ◽  
Michael F. La Fountaine ◽  
John P. Handrakis ◽  
Christopher R. West ◽  
Aaron Phillips ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Autonomic Nervous System Dysfunction ◽  
Autonomic Nervous ◽  
Cord Injury

What is the Autonomic Nervous System?

2002 ◽  
Author(s):  
Daniel J. Wallace ◽  
Janice Brock Wallace
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Blood Vessels ◽  
Parasympathetic Nervous System ◽  
Acute Stress ◽  
Local Level ◽  
Cranial Nerves ◽  
Autonomic Nervous ◽  
Bowel Movements

The autonomic nervous system (ANS) has already been introduced; let’s summarize what we know about it so far. Part of the peripheral nervous system, the ANS consists of the sympathetic nervous system (SNS), which consists of outflow from the thoracic and upper lumbar spine, and the parasympathetic nervous system (PNS), including outflow from the cranial nerves emanating from the upper spine and also from the mid-lumbar to the sacral areas at the buttock region. Several neurochemicals help transmit autonomic instructions. These include epinephrine (adrenaline), norepinephrine (noradrenalin), dopamine, and acetylcholine. This chapter will focus on how abnormalities in the regulation of the ANS cause many of the symptoms and signs observed in fibromyalgia. Our body has numerous receptors or surveillance sensors that detect heat, cold, and inflammation. These ANS sensors perform a function known as autoregulation. As an example of how the ANS normally works, why don’t we pass out when we suddenly jump out of bed? Because the ANS instantly constricts our blood vessels peripherally and dilates them centrally. In other words, as blood is pooled to the heart and the brain, the ANS adjusts our blood pressure and regulates our pulse, or heart rate, so that we don’t collapse. On the local level, these sensors dilate or constrict flow from blood vessels. They can secondarily contract and relax muscles, open and close lung airways, or cause us to sweat. For instance, ANS sensors can tone muscles, regulate urine, and regulate bowel movements, as well as dilate or constrict our pupils. The SNS arm of the ANS is our “fight or flight” system, releasing epinephrine and norepinephrine as well as a neurochemical called dopamine. Whereas the SNS often acts as an acute stress response, the PNS arm tends to protect and conserve body processes and resources. The SNS and PNS sometimes work at cross purposes, but frequently they work together to permit actions such as normal sexual functioning and urination. How do the workings of the ANS relate to fibromyalgia? The SNS is underactive in fibromyalgia in the sense that an increased ratio of excitatory to inhibitory responses from central sensitization results in lower blood flow rates, leaky capillaries, at relatively low baseline blood pressure.

scholarly journals MORPHOLOGY AND FUNCTION OF THE AUTONOMOUS NERVOUS SYSTEM

2020 ◽  
Vol 20 (1) ◽  
pp. 212-217
Author(s):  
A.P. Stepanchuk
Keyword(s):  
Spinal Cord ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Abdominal Cavity ◽  
Nerve Cells ◽  
Autonomous Nervous System ◽  
Autonomic Nervous ◽  
Lumbar Spinal ◽  
The Brain ◽  
Lateral Nuclei

The autonomic nervous system consists of the sympathetic and parasympathetic divisions. The central part is represented by supra-segmental and segmental centres. Parasympathetic segmental centres in the brain are accessory nucleus of the oculomotor nerves, superior salivary nucleus of the facial nerve, inferior salivary nucleus of the glossopharyngeal nerve and dorsal nucleus of the vagus nerve. In the spinal cord, these are the intermediate lateral nuclei. Sympathetic segmental centres in the brain are absent, and in the spinal cord, intermediate-lateral nuclei are located in the lateral horns in the eighth cervical, all thoracic and 1-2 lumbar spinal segments. The peripheral part of the autonomic nervous system is represented by pre-nodal and post-nodal branches, paravertebral, prevertebral and terminal nodes and plexuses. The intramural part of the autonomic nervous system lies in the larger part of a wide and narrow-loop net and represented with a large number of nerve cells different by their shapes and sizes and clustered as intramural nodes, or individual nerve cells included along the net loops. The autonomic plexuses of the abdominal cavity are topographically divided into celiac, superior and inferior mesenteric, abdominal aortic, mesenteric, superior and inferior hypogastric region.

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