PHYSIOLOGICAL STUDIES OF GUSTATORY MECHANISMS 



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a phasic response in the chorda tympani nerves of calves, lambs, and goats. 

 This substance elicited a relatively larger integrated response in the pig and 

 the dog. 



80€ 6L0SSDPHA8Yli6EAL NERVE 



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Fig. 16. Records from the whole lingual branch of the glossopharyngeal nerve 

 of a dog. Recording procedure same as for Figs. 1 1 and 14 except the Ringer's 

 solution was applied to the tongue approximately 10 sec before each record was 

 made. A, Ringer's solution. B, Distilled water. C, 0.46 m sucrose in Ringer's 

 solution. D, 0.5 m sodium chloride. E, 0.02 m quinine hydrochloride in 

 Ringer's solution. F, 0.2 m acetic acid in Ringer's solution (Kitchell, 



unpublished). 



The neural responses recorded in the lingual branch of the glossopharyn- 

 geal nerve following the application of the 4 test solutions is illustrated in 

 Figs. 14-16. Mechanical stimulation of the tongue near the vallate 

 papillae produced neural responses of larger magnitude than were ob- 

 tained in the chorda tympani nerves using similar methods of stimulation. 

 The rate of flow of the solutions from the burette had to be carefully ad- 

 justed to minimize stimulation of mechanoreceptors. The flow of test 



