484 



TEXT-BOOK OF PHYSIOLOGY. 



is of the opinion, that if the lesion is small and at a sufficient distance 

 from the white fibers of the capsule, there may even be no initial 

 hemiplegia; neither motor nor sensory paralysis will arise if the lesion 

 is confined to the gray matter. 



It is stated by some experimenters that localized injuries, both 

 experimental and pathologic, are followed by a persistent rise of 

 temperature, varying from i to 2.6 C. 



The Optic Thalami. From the anatomic relation of the optic 

 thalami to the general and special sense nerve-tracts, on the one 

 hand, and to the cerebral cortex, on the other hand, it is assumed 



that they are connected 

 with the production of 

 sensations both general 

 and special, and act as 

 intermediates between 

 the peripheral sense- 

 organs and the cortex. 



The results of ex- 

 perimental stimulation 

 and destruction of the 

 thalami are extremely 

 contradictory and fail to 

 throw much light on 

 their functions. Ferrier 

 states that destruction 

 of the posterior part of 

 one thalamus produced 

 blindness in the opposite 

 eye and impairment of 

 the sense of touch and 

 pain in the opposite side 



of the body. In a pa- 



f - . 11rir j pr t h p rarp n f 

 fQt under toe care 



HughlingS-Jackson there 



was blindness in the 

 . , , ,, f , 



e y e > 



loss of hearing in the left 

 ear, impairment of taste on the left side of the tongue, and a diminu- 

 tion of the sense of touch on the left side of the body. Postmortem 

 examination showed a patch of softening in the posterior part of the 

 right thalamus, the remainder of the organ being normal. 



It is probable that in the thalamus visual, tactile, and labyrinthine 

 impressions are received, coordinated, and reflected outward, with 

 the result of producing various adaptive motor reactions connected 

 with station and equilibrium. It is also believed by some investigators 



FIG. 219. VERTICAL SECTION THROUGH THE 

 RIGHT CEREBRAL HEMISPHERE IN FRONT OF 

 THE GRAY COMMISSURE, i. Caudate nucleus. 

 2. Corpus callosum. 3. Pillars of the fornix. 

 4. Internal capsule. 5. Optic thalamus. 6. 

 Gray commissure. 7. External capsule. 8. 

 Claustrum. 



