THE AUTONOMIC NERVOUS SYSTEM 903 



irritability set up reflexly in the pharynx in much the same way as is the 

 hypersensitivity of the skin in regions of referred pain. Spasms in skele- 

 tal muscles are also produced in tuberculosis by reflexes arising from 

 the lung. These are reactions depending on visceral afferent fibers. 

 Reflex conditions arise from the viscera which affect other viscera 

 through the autonomic efferents. Dmitrenko accelerated the respira- 

 tion and pulse in dogs and raised their blood pressures by stimulating 

 the stomach in various ways, as by distention with balloons. The vom- 

 iting of pregnancy, menstruation, and the menopause, and of whooping 

 cough, the gastrointestinal disturbances which may follow injury to the 

 testis, etc., are attributed by certain clinicians to reflex effects carried 

 out through the autonomic nervous system. 



