Brain surgery . vements of the upperextremity; the shoulder motions being controlled inthe anterior and upper part of this area, the elbowmotions in its middle part, and the hand and fingermotions in its posterior and lower part. The upper third of the anterior and posterior cen-tral convolutions including their junction in the para-central lobule controls the motions of the lower ex-tremity ; the thigh, knee, foot, and toes being governedby various parts of this area from before backward inthe order named. It will be noticed that the parts susceptible of the •4 BRAIN SURGERY. finest and most
Brain surgery . vements of the upperextremity; the shoulder motions being controlled inthe anterior and upper part of this area, the elbowmotions in its middle part, and the hand and fingermotions in its posterior and lower part. The upper third of the anterior and posterior cen-tral convolutions including their junction in the para-central lobule controls the motions of the lower ex-tremity ; the thigh, knee, foot, and toes being governedby various parts of this area from before backward inthe order named. It will be noticed that the parts susceptible of the •4 BRAIN SURGERY. finest and most delicate movements, those directed bythe most acute sensations, the lips, the fingers, andthe toes, lie furthest back in the motor area, chiefly inthe posterior central convolution. Lesions in this con-volution almost always cause some loss of tactilesensation as well as paralysis, and hence this area isthought to be the seat of tactile sensations as well asof movements, while some cases point to the localiza-. Fig. 1.—Diagram (after Eberstaller) of the Fissures and Convolutions of the Con-vexity of the Right Hemisphere of the Brain. Tlu relative depth of the fissuresis indicated by the shading. The extent of the functional areas is indicated bythe dotted lines. tion of muscular sensations in the area just behindthat of motion. The median surface of the hemisphere in frontof the paracentral lobule is known to be related tomovements of the trunk in monkeys, but thesemovements are rarely affected by disease in man andtheir cortical representation is still uncertain, though THE DIAGNOSIS OF CEREBRAL DISEASE. 5 a case reported by Horsley points to the cortex infront of the leg area on the convexity as the probablelocation of the trunk area. There are no sharply defined sections of the motorarea to be assigned to special motions. Each motion,each part of a limb, has a wide general representationover the cortex and a special representation at a lim-ited area. Horsley says that th
Size: 2006px × 1246px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookidbrainsur, booksubjectbrain
