HANDBOOK OF PHYSIOLOGY 



NEUROPHYSIOLOOY I 







FIG. 1. Main features of the known connections of the auditory pathways in the cat. .-1, medial 

 geniculate body; B, superior colliculus; C, inferior coliiculus; D, cochlear nucleus; E, superior olive; 

 F, cut section of brachium pontis; 2, corticopontocerebellar pathway; 3, recurrent fibers throughout 

 the auditory projection pathway; 4, commissure of Probst; j, brachium of inferior colliculus; 6, 

 commis.sure of inferior colliculus; 7, nucleus lateral lemniscus; 8, lateral lemniscus; 9, olive cochlear 

 bundle; ;o, cochlear nerve; //, trapezoid body; 12, reticular system (diffuse projection to cerebral 

 cortex). 



ation. Both contain many cell types (28, 68) and 

 several types of axon endings. Of the former, some 

 are recognized as intranuclear short axon cells (28). 

 In the light of present knowledge, there is little evi- 

 dence to tell us what may be the functional signifi- 

 cance of this coinplcx organization or even its signifi- 



cance in terms of distribution of efferent fibers from 

 the cochlear nuclei. Rose et al. (84) have recently 

 demonstrated a functional organization in terms of 

 frequency but have not yet tied this firmly to the 

 histological pattern. For the present, therefore, we 

 have little choice l)ut to ignore most of the organiza- 



