Farmasevtika instituti farmakologiya va klinik farmatsiya kafedrasi

Sensory Pathways for Transmitting Somatic 
Almost all sensory information from the somatic segmentsof the body enters the spinal cord 
through the dorsalroots of the spinal nerves.
Figure 47-2 
Cross section of the spinal cord, showing the anatomy 
of the cord gray matter and of ascending sensory tracts in thewhite columns of the spinal 
cord.
Unit IX The Nervous System: A. General Principles and Sensory Physiology 
574 
The 

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medial branch turns medially first and then upward in the dorsal column, proceeding by way of the 
dorsal columnpathway all the way to the brain.The lateral branch enters the dorsal horn of the cord 
gray matter, then divides many times to provide terminals that synapse with local neurons in the 
intermediate and anterior portions of the cord gray matter.
Medulla oblongata Pons Midbrain 
Figure 47-8 
Structure of the cerebral cortex, showing I, molecular layer; II, external 
granular layer; III, layer of small pyramidalcells; IV, internal granular layer; V, large pyramidal 
cell laye; and VI, layer of fusiform or polymorphic cells. (From Ranson SW, Clark SL [after 
Brodmann]: Anatomy of the Nervous System. Philadelp ia: WB Saunders, 1959.) 
Chapter 47 Somatic Sensations: I. General Organization, the Tactile and Position Senses 
577 
 
The Sensory Cortex Is Organized in VerticalColumns of Neurons; Each Column 
Detectsa Different Sensory Spot on the Body with 
Somatic Sensations: II. Pain, Headache, and Thermal Sensations 
Many, if not most, ailments of the body cause pain.Furthermore, the ability to diagnose different 
diseasesdepends to a great extenton a physician‘s knowledgeof the different qualities ofpain. For these 
reasons, the first part of this chapter is devoted mainly to pain and to the physiologic bases ofsome 
associated clinical phenomena.