280 ORIGINAL ARTICLES AND CLINICAL CASES 



caudate nucleus, three weeks after operation. She approached the 

 dish, walking in a rather wide circle, but as soon as her mouth came 

 in contact with the food, which stimulates the normal rat to squat and 

 assume a definite feeding position, she turned sharply to the right, the 

 position shown at A. She then rotated several times to the right until 

 by chance her nose was braced against the side of the dish (B). A 

 similar position with hyperextension of the left legs is shown at C. 

 Once such a feeding position has been attained it may be held for some 

 time and a gradual relaxation of the strained posture of the body then 

 appears. Thus, at D, the animal was held in contact with the food for 

 about thirty seconds, then gradually released. She then maintained the 

 normal feeding position for nearly a minute, turning only gradually to 

 the right, as successive bites were taken from the edge of the cube of 

 bread, and finally becoming overbalanced and falling. 



In all the activities of such animals, the greatest disturbance of 

 co-ordination appears when some new adjustment to the environment is 

 necessary. Initiation of locomotion, change in direction of locomotion, 

 assumption of a sitting posture, stretching forward for food, scratching, 

 &c, are attended by sudden rotations as though the difficulty were 

 chiefly in gaining a new posture or in initiating a new activity. Yet 

 the activities are initiated and the disturbances are compensated for in 

 ways that indicate that the difficulty is not at the level of the most 

 complex integrations. Thus, in 1917, Franz and the writer reported 

 the case of an animal with complete destruction of the motor cortex and 

 degeneration of one striate nucleus, which learned the " simple maze." 

 The maze used had essentially the same ground plan as the problem 

 box shown in fig. 14. The animal was trained to go constantly to the 

 left. He rotated and fell constantly to the right and at first could not 

 make the turn to the left. He finally learned to grasp the end of the 

 partition with his left hind foot and, with this as a pivot, to swing his 

 body to the left and so enter the food compartment. Fig. 14 shows a 

 more common type of adjustment where the drive toward the goal is 

 maintained in spite of the motor difficulty. 



Such adaptations seem to prove that the interference is not with the 

 more complex integrations of voluntary reactions. The compensations 

 rather suggest those described by Luciani [13] for dogs after cerebellar 

 injury, where the tendency to rotate is compensated for by walking 

 with the body curved, and where the lesion admittedly interferes only 

 with reflex tonic control. 



The recent discussions of postural reflexes by Sherrington [17] and 



