728 



A TEXTBOOK OF PHYSIOLOGY 



right hemianopia blindness in the right half of each visual field. 

 A lesion of the region above the calcarine fissure causes hemianopia 

 in the right lower part of the visual fields of both eyes ; of the region 

 below the calcarine fissure, in the right upper part of both visual 

 fields. The external surface of the occipital lobe is probably 

 concerned in psychic processes connected with the recognition of the 

 things seen. 



Parietal and temporal 

 centres of association 



nsuiar centre 

 of association 



Auditory 



projection 



centre 



" 



.Olfactory and 

 gustatory projection 

 centre 



c nfr e of association 



Fio. 444. DIAGRAMS OF THE "CENTRES OF PROJECTION" AND "CENTRES or 

 ASSOCIATION." (Bolton, after Flechsig.) 



The small dots are placed in the chief focus of each centre of projection; around these 

 chief foci are regions (larger/lots) to which a. smaller number of projection-fibres 

 pass. 



The receptive area for hearing is situated in the superior temporal 

 lobes (Fig. 444). It is connected with the inferior corpora quadri- 

 gemina by the auditory radiations, which pass through the most 

 posterior part of the internal capsule. The effect of stimulation 

 points to this region of the brain as being concerned in hearing. In 



