File:Diseases of the nervous system - a text-book of neurology and psychiatry (1915) (14596126388).jpg

Identifier: diseasesofnervo00jell (find matches)
Title: Diseases of the nervous system : a text-book of neurology and psychiatry
Year: 1915 (1910s)
Authors: Jelliffe, Smith Ely, 1866-1945 White, William A. (William Alanson), 1870-1937
Subjects: Mental Disorders Nervous System Diseases
Publisher: Philadelphia : Lea & Febiger
Contributing Library: Columbia University Libraries
Digitizing Sponsor: Open Knowledge Commons

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
Corti in the cochlea. They respond to sound stimuli of 11 octaves,i. e., from 10 to 7840 double vibrations. Ordinary conversational ormusical sounds usually lie within 16 to 4032 vibrations. Space orien-tation through sound is purely associative. The chief avenues forsound conduction to the receptors is the auditory canal, but soundconduction is also possible by way of the bones, chiefly of the skull,in part by other bony structures. From the cochlea the branchescoalesce to form the acoustic nerve which, passing in the auditorycanal with the facial, enters the medulla at about the cerebellopontileangle. The sensory ganglion is the tuberculum acusticum. Thefurther course of the pathways is illustrated in Figs. 112, 113, alsosee Plate VIII. DISEASES IN AUDITORY AND VESTIBULAR PATHWAYS 223 The chief disturbances of the auditory nerve are: (1) various formsof deafness. These vary considerably and may be absolute or partial.Certain tones may be cut out and not others, upper or lower tones,
Text Appearing After Image:
Fig. 113.—Central acoustic paths, na, anterior acoustic nucleus; ta, acoustic tubercle;Sta, acoustic striae; os, superior olive; ctr, trapezoid body; nVI, abducens nucleus;nil, lateral lemniscus; cqi, cqs, posterior and anterior corpora quadrigemina; cgi, exter-nal geniculate body; st, acoustic path to cortex; It, temporal lobes; th, thalamus.(Bechterew.) 224 S^NSORI-MOTOR NEUROLOGY—CRANIAL NERVES sometimes intermediate tones drop out (hearing scotomata, analogousto optic scotomata, are not infrequent in hysterical reactions, dementiaprecox, in multiple sclerosis, paresis, tabes, etc.). These anomalies ofhearing are chiefly peripheral, either in the primary receptors oroccasionally in the ganglion. Paracusia (buzzing, whistling, crackling),are also peripheral for the most part, but may also be central as inpsychotic or psychoneurotic syndromes.

Note About Images