CONTENTS xxxi 



PAGE 



§ 479. The phenomena and causation of vertigo 733 



§ 480. Forced movements 735 



§ 481. The parts of the middle brain concerned in the coordination of 



movements 737 



SECTION III. 



On Voluntary Movements. 



§ 482. The real distinction between voluntary and involuntary movements 739 

 § 483. The cortical motor areas of the dog ; the characters of the move- 

 ments resulting from cortical stimulation 740 



§ 484. The cortical motor areas in the monkey 744 



§ 485. The cortical motor areas in the anthropoid ape .... 748 



§ 486. The movements of cortical origin carried out by means of the 



pyramidal tract ; the nature of the movements so carried out . 749 

 § 487. The results of the removal of a cortical area in dog and in the 



monkey 762 



§ 488. The cortical motor areas in man ; the area for speech . . . 764 

 § 489. The nature of the action of a motor area in carrying out a volun- 

 tary movement ; the characters of aphasia. The same as illus- 

 trated by the area for a limb in the dog ; the influence of 



sensory impulses 769 



§ 490. The relations of the motor area to other parts of the central nervous 

 system ; the motor area employed in movements usually called 



involuntary 773 



§ 491. The passage of volitional impulses along the spinal cord in animals 774 



§ 492. Their passage in man 775 



§ 493. A summary of the chief facts concerning the carrying out of 



voluntary movements 776 



SECTION IV. 



On the Development within the Central Nervous System of 

 Visual and of some other Sensations. 



§ 494. Visual impulses and sensations ; visual fields, and binocular vision 781 

 § 495. The decussation of the optic nerves in the optic chiasma . . . 784 

 § 496. The course of the optic tract. The endings of the optic tract in the 

 lateral corpus geniculatum, the pulvinar and the anterior corpus 

 quadrigeminum ; the results of degeneration and atrophy experi- 

 ments 785 



§ 497. The connection of the three above bodies with the cerebral cortex ; 

 the meaning of the terms, blindness total and complete or par- 

 tial, hemianopsia, amblyopia. The difficulties of interpretation 

 attending experiments on the vision of animals .... 787 

 § 498. The nature of the movements of the eyes caused by stimulation of 



the occipital cortex 790 



§ 499. The effects on vision of removing parts of the occipital cortex in 



monkeys and in dogs ; the teachings of clinical histories . . 791 



