A reference handbook of the medical sciences, embracing the entire range of scientific and practical medicine and allied science . isual sensations the meaning or use of certain kindsof objects, although the individual may still retamthe ability to pronounce the words and have no otheraphasic disorder. The visual disturbances which accompany lesionsof parts of the brain other than the cortex differ forthe different locations of lesions. It is weU knownthat when the retma or the optic nerve is affectedthere is an amblyopia for that eye. A lesion in theoptic tract on the same side produces a hem
A reference handbook of the medical sciences, embracing the entire range of scientific and practical medicine and allied science . isual sensations the meaning or use of certain kindsof objects, although the individual may still retamthe ability to pronounce the words and have no otheraphasic disorder. The visual disturbances which accompany lesionsof parts of the brain other than the cortex differ forthe different locations of lesions. It is weU knownthat when the retma or the optic nerve is affectedthere is an amblyopia for that eye. A lesion in theoptic tract on the same side produces a hemiopiafor the opposite field of vision (the inability to seewith the homolateral parts of the retma;). A lesionin the superior corpus quadrigemmum is not dis-turbing to visual processes per se, but a lesion m thislocation produces an inability to move the eye uponstimulation. This ganglion is connected in an efferentmanner with the nuclei of the third, fourth, and sixtlicranial nerves, and when the impulses cannot passthere results a paralysis or a loss of the associatedmovements for this part of the field. Thus we find FiQ 1043.—Scheme of Impulses from Retina to OccipitalCortex and Nuclei of Cranial Nerves. (HaUiburton, after Schafer.)From each half of the retina; two fibers are represented, one passingby way of the anterior quadrigeminal body, the other by way olthe lateral geniculate body. that the connection is made for both the mt_rinsicand extrinsic movements of the eye through tliesuperior quadrigeminal body. Lesions m the ge-niculate body produce blmdness very similar to thosewhich are produced by destructions of the opticradiations or of the calcarine The study of the degenerations has mdicated thatthe connections of the eye with the remainder of thebrain are (1) through the optic tract with the superiorquadrfgeminal body to the nuclei of the cranial nervesand (2) through the external geniculate body to tne REFERENCE HANDBOOK OF THE MEDICAL SCIENCES Br
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Keywords: ., bookauthorbuckalbe, bookcentury1900, bookdecade1910, bookyear1913
