It is impossible as yet to give any satis factory reason why the auditory nerve in some deaf-mutes is atrophied or degener ated while in others it is not. The ques tion will doubtless be cleared up by a larger number of post-mortem examina tions of deaf-mutes, accompanied by re liable information as to the origin of the deafness.
membrana fcnestne rotundaa; the ment of the stapedius muscle was mov Of the 9 totally deaf, by far the larger number were cases of congenital deaf ness. Of those who could hear and dis tinguish the voice, much the larger num ber were cases of acquired deafness. The causes of acquired deafness were found to be, in half the cases, primary disease or injury in the brain or internal ear, without apparent disease of the mid dle or external ear. Measles and scarlet fever were found responsible for 13 cases. Sixty-one cases of normal membrane were found among the 175 children; 32 showed suppurative disease, and nearly SO catarrhal changes. The pharynx was diseased in most of the cases. J. K. Love (Glasgow :Med. Jour., June, '93).
Post-mortem examination of the ears of a deaf-mute. The case was that of a young man, aged 1S years, who died from pulmonary and intestinal tuberculosis. When 2 V, years old he suffered from scarlatina, and, as a result, became a deaf-mute. In the right ear the patho logical conditions were confined to the labyrinth, and consisted of destruction of its integral parts, the various spaces having undergone ossification. The drum-head and tympanum were quite normal. The ligamentum annulare sta pedis and the membrana fenestrw ro tundx were ossified; but this process was confined to the sides adjoining the in ner ear. In the left ear were found otor rhrea, ossification of the spongy portion of the pars petrosa and of the processus mastoideum, and ossification of the able. The inner ear showed no sign of pathological fluid or new formations. The surface of the brain showed no ab normality. Broca's convolution appeared smaller than normal. The superior tem poral convolution of the left side was also smaller than usual. The micro scopical examination did not show any positive signs of abnormality. These cerebral changes are supposed to result from atrophy consequent upon the in activity of the parts, it being worthy of note that this left-sided atrophy is asso ness (field of vision) with the instrument of Landolt. Conclusions: The reactions
to general sensitiveness and to pain, in the deaf-mute, are very little inferior to the normal. In early life, indeed, there is no difference worthy of note. So also with regard in general to the field of vision; it is normal both in extent and form, except for a, readiness to fatigue, which by itself is anything but a serious ciated with destruction of the right labyrinth. Conclusion that there is good ground for the belief that the fibres of the acoustic nerve cross in the brain. V. Uchermann (Annual, '93).
Examination of the rea,ctions for gen eral and painful sensations in forty-four deaf-mutes with the faradimeter of Edelmen, and of the retinal sensitive sign of ;narked degeneration. The sensi tiveness of the deaf-mute evidently ex presses a, mental development of a, very satisfactory quality, and clearly differ entiates him from such classes as the criminals, the epileptics, and the feeble minded (partial imbeciles), not to men tion more ma,rked forms of degeneration. In spite of the absence of one sense, the sensitive zone of the deaf-mute is not deficient. Various stimuli from all the sources in the sensorimn reach his cortex, and this is in such condition as to be able to normally elaborate the stimuli; hence collies ease of perception and at tention. All the other sensorial sources, if exercised, can supply- the want of a source so full of ideas as is that of hear ing, when the centre is normal. This fact should help our judgment in form ing the scientific diagnosis of the deaf mute. Deaf-mutism, by itself, does not mean serious degeneration. S. Ottolenglii (Jour. of Laryn., Jan., '96).
Case in which there were atrophic changes in the fibres of the cochlear branch occupying the first whorl, the corresponding portion of Corti's organ being reduced to a mere trace, while in the upper whorls it was lower than nor mal, the membrane being rolled up in the rudimentary way.. This and other allied conditions indicated a congenital defect or arrest of development. A. Scheibe (Arch. of Otol., vol. xxiv, Nos. 3 and 4, '97).