The People's Common Sense Medical Adviser in Plain English / or, Medicine Simplified, 54th ed., One Million, Six Hundred / and Fifty Thousand

by Ray Vaughn Pierce

REGIONAL DIVISIONS.

The anterior portion of the cerebrum is devoted to intellectual processes, which freely expend the vital energies. The Intellectual faculties are classified as represented in Fig. 71. The lower portion of the brain, bounded exteriorly by the superciliary ridge, corresponds to the Perceptive, the middle region to the Recollective, and the upper to the Reflective faculties. (See also Fig. 65, b.) If we divide the forehead by vertical lines, as shown in Fig. 71, the divisions thus formed represent respectively, the Active, Deliberative, and Contemplative departments of the intellect, all the processes of which are sustained by vital changes, the transformation of organized materials. No mental effort can be made without waste of nervous matter. The gardener's hoe wears by use, and so does every part of the animal organism. Otherwise, nutrition would be unnecessary for the adult. The production of thought wears away the cerebral substance. In ordinary use, the brain requires one-fifth of the blood to support its growth and repair. Great mental efforts are attended by a corresponding expenditure of vital treasures, which are abstracted from the total forces available for the necessities of the system. To repair the losses thus occasioned, materials are appropriated from the blood, which furnishes supplies in proportion to the demands made by the mental activities. The production of thought wears away the gray matter of the cerebrum as surely as the digging of a canal wears away the iron particles of the spade. The brain would soon wear out did not the nutritive functions constantly make good the waste. The intellect, whether engaged in observation, generalization, or profound study consumes the brain and blood, hence intellectual activity implies VITAL EXPENDITURE. Expenditure is an emphatic word because all functions are essential to the production of this nerve-energy, which returns to the system no equivalent. Physical exercise, although attended by structural waste, is advantageous to the circulation of the blood, nutrition, secretion, and, in fact, beneficial to all the organic processes. This is not true of vigorous and prolonged mental labor, which is not attended by any of these incidental advantages. If a child attends a school in which mental development supersedes physical culture, an inordinate ambition sways the youthful mind, and its baneful effects upon the health soon become manifest. Rigorous application of the intellectual faculties consumes the blood, exhausts the vital forces, weakens the organic functions, while pallor covers the face, and the eyes sparkle with a hectic radiance. The family physician pronounces the condition Anæmia (a deficiency of red corpuscles in the blood), and this change in the quality of the blood is owing to the undue appropriation by the brain. Conversely, if the blood be destroyed, or its vitality reduced, in the same proportion will the mental energies be weakened and all the functional powers of the physical system enfeebled. In brief, if the intellect be unduly exercised, the red corpuscles of the sanguine fluid will be gradually destroyed, and the serum allowed to predominate. The blood becomes weak and watery, the subject is nervous, dropsical, consumptive and derangement of the important functions follows almost invariably. Excessive intellectual activity often produces weak state of the system, and the person thus affected becomes languid, spiritless, and an easy prey to disease. This mental cause and its bodily results may be classified in the following order. Mental Cause: EXCESSIVE MENTAL EXERTION, which produces waste of the brain substance and blood.

	{	VITALEXPENDITURE,
Bodily results:		ANÆMIA,
		A WEAK CONDITION.

This kind of waste is best summed up in the words, VITAL EXPENDITURE. Upon the forehead, as represented in Fig. 72, we will therefore inscribe INTELLECT, ACTIVITY, and VITAL EXPENDITURE. Intellectual employment is usually accompanied by sedentary habits, neglect of healthful exercise, and a deprivation of pure air, to all of which ill health may be attributed. Were the intellectual expenditure arrested, and the forces turned into recuperative channels, many a person would become beautiful with the ruddy glow of health. Without health there is no use for thought; cultivation of the mind is just as natural and essential as the culture of the body, and the trained development of both is needed for mutual improvement.