182 NERVOUS SYSTEM. 



nerves point directly to their function. The most notable 

 fact observed after this operation is, that the movements of 

 the tongue are entirely lost, while the tactile and gustatory 

 senses are not affected. These phenomena have been accu- 

 rately described by Mayo, 1 Panizza, 3 Magendie, 3 and many 

 others. Perhaps the most varied experiments made upon 

 animals are those of Panizza. These have been fully detailed 

 in connection with the subjects of mastication and degluti- 

 tion. They consist simply in loss of power over the tongue, 

 with considerable difficulty in deglutition. We have repeat- 

 edly noted all of these points and demonstrated them to 

 medical classes. 



In the human subject, the sublingual is usually more or 

 less affected in hemiplegia. In these cases, as the patient 

 protrudes the tongue, the point is deviated. This is due to 

 the unopposed action of the genio-hyo-glossus upon the sound 

 side, which, as it protrudes the tongue, directs the point 

 toward the side affected with paralysis. 



A disease of rather rare occurrence has lately been de- 

 scribed under the name of glosso-labial paralysis, which is 

 characterized by paralysis of the sublinguals, affecting also 

 the orbicularis oris, and frequently the intrinsic muscles of 

 the larynx. The phenomena referable to the loss of power 

 over the tongue correspond to those observed in animals 

 after section of the nerves. Patients affected in this way 

 experience difficulty in deglutition, and, in addition, we note 

 an interference with articulation, which cannot be observed 

 in experiments upon animals. "We lately had a case of this 

 disease under observation in the Bellevue Hospital, the phe- 

 nomena of which were peculiarly interesting from a physio- 

 logical point of view. This patient presented complete 

 paralysis of the tongue, with considerable difficulty in deglu- 

 tition, probably from the tongue-affection. The orbicularis 



1 Loc. cit. 



2 PANIZZA, Nouvelles recherches experimentales sur les nerfs. Gazette medicate, 

 Paris, 1835, p. 419. 3 j^ ^ 



