I20 BRAINS OF RATS AND MEN 



cortex are changed. In man more precise clinico- 

 pathological analysis is rapidly yielding results which 

 can be interpreted, at least provisionally, in terms of 

 normal functions. In man the olfactory component 

 of both striatal and amygdaloid complexes is greatly 

 reduced, with increase in the thalamic components. 

 The afferent thalamic fibers distribute to both cau- 

 date nucleus and putamen, coming by way of the ansa 

 lenticularis and internal capsule. The chief efferent 

 path from these parts of the striatum is to the globus 

 pallidus, which in turn sends strong tracts into the 

 lower motor centers, particularly the subthalamus 

 and motor tegmentum of the midbrain. 



Recent students of the human corpus striatum are 

 inclined to deny any direct anatomical connection 

 between the cortex and the striatum, but certainly 

 these parts are in intimate physiological relations 

 somehow. One experimental study (Griinstein, 1924) 

 has demonstrated in the dog a direct path from the 

 frontal cortex to the globus pallidus. There are prob- 

 ably some cortico-striatal connections in man. 



Kinnier Wilson (1924) brings out important dif- 

 ferences between movements evoked by electrical 

 stimulation of the cortex and those evoked by stimu- 

 lation of centers lying below the thalamus. The for- 

 mer are phasic, that is, they endure only during stimu- 

 lation. But stimulation of the midbrain (except its 

 pyramidal tract) produces postural movements which 

 endure long after cessation of the stimulus. The pos- 



