44 PHYSIOLOGY OF ALIMENTATION. 



nics are stimulated was secondary to the anemia brought 

 about by this means. But, as BAYLISS and STARLING have 

 shown, such inhibition of intestinal movement still follows 

 stimulation of the splanchnics in freshly killed animals, 

 in other words, when no circulation is present. Nothing 

 definite seems to be known regarding the role of the plexuses 

 of AUERBACH and MEISSNER in the small intestine. Whether 

 they are, in the last analysis, responsible for the rhythmical 

 contractions of the jejunum and ileum seems questionable. 

 This power probably resides in the musculature itself. 



Stimulation of certain regions in the ganglia at the base 

 of the brain and certain portions of the spinal cord leads 

 to muscular contractions or relaxations in the small in- 

 testine by way of the vagus and sympathetic nerves supply- 

 ing the gut. Some connection must also exist between the 

 cerebrum and the small intestine, for, as the next para- 

 graphs show, mental states may cause a stoppage of all 

 movement. 



It has long been a recognized clinical fact that emo- 

 tional states such as fear, anxiety, sorrow, etc., bring 

 in their train a long series of digestive disturbances. 

 The physiological pathology of these disturbances has re- 

 cently been put on a more scientific basis by a series of 

 experimental observations. We shall later become ac- 

 quainted with facts which indicate how largely certain secre- 

 tory phenomena of the alimentary tract are influenced by 

 psychic states. Here mention must be made of the important 

 relation which exists between mental states and the move- 

 ments of the stomach and intestine. 1 



CANNON observed in his studies of gastro-intestinal move- 

 ments that female cats were much more suitable for 

 experimental purposes than males. Even though treated 

 exactly alike the movements which appeared almost with- 



1 CANNON: American Journal of Physiology, 1898, I, p. 380; ibid., 

 1902, VI, p. 260, 



