Identifier: textbookofphysio1911howe (find matches)
Title: A text-book of physiology for medical students and physicians
Year: 1911 (1910s)
Authors: Howell, William H. (William Henry), 1860-1945
Subjects: Physiology
Publisher: Philadelphia, London, W.B. Saunders company
Contributing Library: Columbia University Libraries
Digitizing Sponsor: Open Knowledge Commons

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
ollows GENERAL PHYSIOLOGY OF THE CEREBRUM. 195 the order of the cranial and spinal nerves. Within each areasmaller centers may be located by careful stimulation; thus,the hand and arm area may be subdivided into centers for thewrist, fingers, thumb, etc. More recently, Sherrington andGreenbaum,* making use of electrical stimulation, unipolarmethod, have explored carefully the motor areas in the monkey.They state that these areas do not extend back of the centralsulcus, but lie chiefly along the anterior central convolution,as represented in Figs. 87 and 88 extending for only a smalldistance on to the mesial surface of the cerebrum. The areathus delimited by physiological experiments is the regionfrom which arises the pyramidal system of fibers, and clin-ical experience has shown that lesions in this part of the cortexare accompanied by a paralysis of the muscles on the other Sulc. Central, Anus, * Vagina, „ . „ \ / Sulc.precentr.morg. Sulccculoso \***7&*v^ s Sulc.parieCooccig.
Text Appearing After Image:
Stdccalcarin C.S.S. te. Fig. 88.—To show extension of motor areas on to the mesial surface, brain of chim-panzee.—(Sherrington and Greenbaum). Mesial surface of left hemisphere: Stippled regionmarked L E G gives the motor area for lower limb; /, s, and h indicate regions from whichmovements were obtained occasionally with strong stimuli; /, foot and leg; s, shoulder andchest; h, thumb and fingers. The shaded area marked EYES indicates a region stimulationof which gives conjugate movements of the eyes. side, particularly in the limbs. Pathological or experimentallesions here, moreover, are followed by a degeneration of thepyramidal neurons,—a degeneration which extends to the ter-mination of the neurons in the cord. With these data we can con-struct a fairly complete account of the mechanism of voluntarymovements. The initial outgoing or efferent impulses arise in thelarge pyramidal cells of the motor areas and proceed along theaxons of their neurons to the motor nuclei of the cr

Note About Images