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transmission of sensations of touch to the brain the sen- 

 sation is localized and the tactile sensation becomes a 

 tactile perception. 



There are three main divisions of the sense of touch: 1. 

 sensations of touch proper or tactile sensation; 2. sen- 

 sations of temperature, and 3. sensations of pain. The 

 temperature sense is the transmission by the skin of sen- 

 sations not so much of a certain degree of heat or cold as 

 of the difference between the temperature of an object 

 and that of the skin. The longer an object is in contact 

 with the skin, the less conscious the person is of it, not 

 only because it becomes of the same temperature, but 

 also because he becomes accustomed to it. There also 

 seem to be in the skin, besides the touch corpuscles, two 

 other terminal organs with separate nerve fibers, the one 

 for detecting heat, the other cold; for there are places on 

 the body where heat can be detected and cold cannot, 

 and vice versa. 



Sensations of pain may be merely an exaggeration of 

 tactile sensation, as in too hard pressure or too great heat, 

 but there seems to be also a sensation of pain in the skin. 

 All organs are said to have common sensibility to pain 

 and any exaggeration of this sensibility causes a sensa- 

 tion of pain. All the special senses require a certain 

 amount of judgment in the interpretation of the sensa- 

 tions they convey. 



