SUPPOlir, MO'I'ION, AND SENSATION 



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frcntal 

 ctrscr 



occipital' 

 areo: 



temporal arecc 



Two I'lKurt's illustralinK tiie intercoiniiiunicating pathways of nerve libers in 

 the human brain. 



a. Various association fibers of the human brain. ,1, between adjacent areas; 

 B. between frontal and occipital areas; (;, D, between frontal and temporal 

 areas; E, between occipital and temporal areas. Note the corpus callosum 

 which contains larf):e groups of association fibers and connects the cortex of the 

 right cerebral hemisphere with that of the left. The caudate nucleus, CN, and 

 the thalamus, OT, both contain gray matter. 



■m^-fr^^t 



b. Scheme of projection fibers connecting the cerebrum and other parts of 

 the brain. .1, tracts fnmi frontal lobe to the pons varolii and thence to the 

 cerebellum via (!; B, motor (pyramidal) tracts; C, sensory tracts; D and E, 

 the visual and auditory tracts, respectively; F, fibers connecting the cerebrum 

 and cerebellum ; 6', fibers connecting the cerebellum and the brain stem ; 11, 

 fibers between the cerebellum and the cord ; ./, fibers connecting the auditory 

 nucleus and the brain stem ; A', crossing over of motor (pyramidal) tracts in the 

 brain stem ; V7, fourth ventricle. The numbers refer to the cranial nerves. 

 (Both modified from Starr.) 



