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abnormal actions of brain, and into so of will. The food upon which we submuch pseudo-scientific jugglery, the world at large is unquestionably the gainer in respect of the new and rational light which has been thrown upon phases of mind. Or, when the hallucinations of the ghost-seer are proved to be subjects of physiological study, and when the production of his inverted mental images is capable of being duly explained on known principles of life science, we may congratulate ourselves on having snatched another mystery from the charlatanism of ignorance, and on having expelled so much superstition from the world. Thus, judging even the most recondite study of mind from a rigidly utilitarian point of view, we may discover that its effects must leave their wholesome mark on the social life of our day, and on that of succeeding generations as well. The gains of knowledge are in fact among the saving clauses which are now and then added to the large and complex roll of the constitution of man.
It may be well to preface such a simple study of mind and body as that on which we purpose now to enter by a glance at some of those general relations between the material frame and its immaterial emotions which serve to demonstrate the tacit harmony exhibited by the powers which rule and the sub ject that obeys. No facts of physiology stand out in bolder relief than those which deal with the common and united action of brain and body, in the ordinary affairs of every-day existence. So perfectly adjusted is this co-operation between body and mind we speak of, that in the vast majority of instances we ourselves the very subjects of its action-may be utterly ignorant of the existence of any such league. Like the system of secret espionage which in its most perfect phases moves and lives with us and beside us all unsuspected and unknown, the operations which issue from the head-centre of our corporeal government may be absolutely hidden from us while continually we live and act under their behests. literally take no thought for the morrow of our existence, because we are accustomed to have so much of that existence regulated independently of consciousness, and certainly without the exercise
sist is inspected, so to speak, on its
since it is within the bounds of probability that, were the control of such important processes a matter of unremitting attention, the exigencies of human life, by withdrawing our attention from their due regulation, might conduce to the premature ending of life itself, while sleep itself in such an event would be an impossible condition. In many other ways and fashions does the brief chronicle of the bodily rule bring forcibly before us the independence of our attention and consciousness in so far as the government of every-day existence is concerned. The morning walk to business through the crowded thoroughfares, when we are wrapt in the mantle of deepest thought-with eyes in the mind," although ostensibly bent on outward things-and when we find our steps guided harmoniously toward our appointed end, illustrates but anWe other phase of the unconscious ruling of our lives. And the phenomena of the sleep-vigil, when, wrapt in the mantle of fancies and acted thoughts, we may walk fearlessly on the house-tops, show us in another fashion the action of ac
tive brain and body upon unconscious mind.
Thus it seems perfectly clear that in many of our daily actions we pass automatically through existence, dreaming no more than does the wound-up watch of the mechanism in virtue of which we execute our common movements, but regulated at the same time by an internal power which now and then asserts it sway over the vital machinery, as if to remind us that we possess the higher attributes of reason and will. If it be true, as we have shown, that over the bodily processes brain asserts an autocratic sway, it is equally noteworthy that under the influence of what, for want of a clearer term, we may call conscious mind, the automatic rigor and regularity of life may be suspended and overruled. Take as a fitting and as an interesting example the difference between the ordinary unconstrained action of the heart and its behavior under the influence of mental emotion. If, as Cowper figuratively puts it,
nerves regarded as distinct from that main system (consisting of brain and spinal cord with their nerves) which we are accustomed to speak of as the nervous system" of the body. From the sympathetic nerves, then, branches pass into the heart's substance. But the system of nerves which owns the brain as its head, also possesses a share in the heart's regulation. Nerves are supplied to the organ from a very remarkable branch, which, with more respect for scientific terminology, perhaps, than for the reader's feelings, we shall name the pneumogastric nerve. This latter nerve originates from the upper portion of the spinal cord, esteemed, and justly so, as the most sensitive and important of the brain centres. So much for an elementary lesson in the nervous supply of the heart; the outcome of such a study being, that the heart much resembles a conjoint railway station, in which three companies possess If, as companies possess an interest, and whose lines enter the structure. The chief proprietors of the station are represented by the small nerves and nervecentres which belong to the heart's own substance, while the fibres of the sympathetic nerve, and those of the pneumogastric nerve, represent the other lines that traverse the common territory, and affect the traffic carried on within its bounds.
May give a useful lesson to the head," it is no less true physiologically that the head may occasionally give anything but a salutary lesson to the heart. It was Molière and Swift who, in their day, justly ridiculed, as physiology proves, the idea that the heart's regular action depended upon some mysterious "pul sific virtue.' Within the heart's own substance-and it must be borne in mind the centre of the circulation is simply a hollow muscle-lie minute nerves and nerve masses which govern its ordinary movements, and are responsible for its unconstrained working. The regular motions of the heart thus present little difficulty in the way of theoretically understanding their origin and continuance. As other musclessuch as those of the eyelids or of the breathing apparatus-possess a regular action, and are stimulated at more or less definite intervals, so the heart itself simply acts in obedience to the defined nervous stimulation it undergoes. But it so happens, that other two sets of nerves are concerned more or less intimately in the affairs of the heart. There exist, for example, the "sympathetic nerves" as they are called, which form part of a peculiar system of
Now, in the relations borne by these various nerves to the work and functions of the heart, we may find a very typical example of the dominance occasionally assumed by the mind over a function of the body which, under ordinary circumstances, is carried on without the control of the head-centre of the framejust, indeed, as the head of a department may sometimes interfere with the placid way of life by means of which his efficient subordinates may discharge the duties they owe to the country at large. For, what has experimental physiology to say regarding the explanation of the effects of joy or sorrow, fear and anguish, and the general play of the passions on the heart? Under the influence of the emotions, the organ of the circulation is literally swayed beneath varying stimulation, just as in metaphor we describe it as responding to the conflicting thoughts, which, while
they primarily affect the brain, yet in a secondary fashion rule the heart and other parts of the body. The trains of thought in fact despatch to the heart, along either or both of the nerve-lines already mentioned, portions of their influence, with varying and different effects. Take for instance the effects of fear upon the heart-throbs. Who has not experienced the stilling of the heart's action which a sudden shock induces or that chilling sensation, accompanied by the sudden slowing of the pulses, which every poet has depicted as the first and most typical sign of the startled mind? Such a familiar result of strong emotion illustrates the effect of mind upon body in a fashion of all others most clear and intelligible. Here 'inhibitory" action has take place, through the medium of the " pneumogastric" nerves. By irritating or stimulating these nerves, we may slow the heart's action, or may cause that action to cease. It is from some such source also, that the influence of fear, or of that emotion which holds us rapt "with bated breath," or which keeps us "breathless with adoration, proceeds. Like the action of the heart, the process of breathing responds to the will and sway of that mental counsellor who may sometimes not over-wisely strain his authority, and abuse the prerogative with which he is invested. Similarly, the sacred source of sympathetic tears rests in the mental emotion and its effect upon the tearglands of the eyes; and such unwonted stimulation of these latter organs has come to be associated with certain emotions as the most stable expression of their existence. In such a study we may well discover how the physical and material basis whereon the expression of the emotions rests, is in reality constituted by the action and inter action of like processes to these we have been considering. An inhibition conveyed from brain to heart, and its visible effects on the body, together form the outcome of emotion, or expression, which, by long repetition in the history of our race, has come to be recognized as a sure sign and symptom of the thoughts and ways of mind.
This inhibition of the heart and its action, however, is not the only influence
which is brought to bear on the normal work of that organ. If it is slowed by fear, it is stimulated by joy; if it is chilled by anguish, it is quickened by hope; and if the pallid countenance be an index of the one set of emotions, no less is the flushed visage and mantling color the true expression of the other. By what means are the trains of thought laden with the hopes and joys of life made to affect the heart? To what do "Sensations sweet,
Felt in the blood and felt along the heart," owe their propagation and conveyance? The answer is found in a study of the sympathetic system of nerves and its influence on the circulation. Experiment and analogy clearly prove, that through these latter nerves, the pulses of joy affect the throbs of the heart, and quicken its pulsations. The sympa thetic nerves are thus the antagonists of the inhibitory fibres before-mentioned, which slow the heart's action, and chill the pulses of life. True, they are not of such powerful kind, and their action is not of such marked character as that of the fibres which retard the throbs of the heart. Still, the influence of the lines along which the impulses which quicken its action run, is marked and distinct enough; and it may be logically enough conceived, that in the subject of the beaming eye, in whose breast hope ever renews her flattering tale," the sympathetic impulses have acquired a power unknown to the mind harassed by continual fears. And in a manner similar to that in which the cheering influences of life pass to quicken the action of the heart, are there more visible expressions of the emotions produced, in the tell-tale blush and in the mantling color. Donne gives vent to no mere poetic phantasy, but declares a veritable fact of physiology, when he declares, in his Funeral Elegy "On the Death of Mistress Drury," that
axation, and having had withdrawn the natural stimulus to moderate contraction, which is part of their ordinary duty. In what way has the head of the department interfered with the ordinary routine of the body? The answer is supplied by the knowledge we have already gained respecting the control of the forces which provide for the due circulation of the vital fluid, and also by experimentation upon the rabbit's ear. When the sympathetic nerves are affected, the heart's action, as we have noted, is quickened, and a greater amount of blood is sent through the vessels. When we divide the sympathetic nerve which supplies the blood-vessels of the ear, these vessels become dilated, and the rabbit's ear exhibits the same phenomena seen in the blushing countenance of the human subject. On the sympathetic system, then, we must lay the burden of any complaints we have to make respecting the "damask cheek" of every-day life. And conversely, to the same lines of nerve which speed the heart's action we must give the credit of causing the pallid countenance of fear or despair. When the cut end of the sympathetic nerve in the rabbit's ear is irritated, we perceive the ear to become pale, and its temperature to decrease. This result arises from our conveying to the nerves of the blood-vessels some stimulus resembling that we have deprived them of, so that they contract overmuch, and thus expel the blood from the surface over which they are distributed. But the slowing of the heart in the ordinary course of life is probably a matter with which the inhibitory nerves have to do, and thus upon the pneumogastric fibres we may rest the pale cast of the human face divine. Not to be passed over without remark, are the consequences to our health and physical well-being which flow from such overriding by the nervous system of the ordinary processes and acts of life. When an influenza, or some still more serious internal disturbance of our healthy equilibrium, occurs, we may trace the affection in question to the influence of cold on the skin (as in a chill) acting upon nerves which regulate the blood-vessels and their contraction. Thus, to descend from philosophy to broad utilitarianism, it is not the least
important effect of studies dealing with the mechanism of body and mind, that they may explain to us with equal facility the rationale of the emotions or the reason why we "catch a cold."
The ordinary relations between body and mind may thus be demonstrated by the study of some of the simplest actions of bodily mechanism. On the other hand, this relationship may be equally apparent, and may be even more forcibly shown in some of its less understood phases, by a reference to states which as a rule are known to the physiologist or physician alone. In proof of this fact let us note the effect of some strong mental impressions upon the physical constitution. Here we may meet with illustrations in themselves of literally wondrous nature, and which reveal a power of affecting the body through the mind such as would scarcely be deemed possible under well-nigh any circumstances. Some curious instances of the effects of ill-governed rage, of violent temper, and of fear, upon the frame may be first glanced at. Sir Astley Cooper long ago drew attention to the high importance of the mother preserving a quiet mind and demeanor during the care and nurture of her child. This authority illustrates his advice by several instances in which some remarkable and unknown effects appear to have been produced in the maternal frame by passion and by fright. An instance in point is given by Dr. Andrew Combe. A soldier was billeted in the house of a carpenter, and having quarrelled with the latter, drew his sword to attack his host. The wife of the carpenter interposed, and, in an excited state, wrenched the sword from the soldier and broke it in pieces, the combatants being thereafter separated by the interference of the neighbors. Laboring under the strong excitement, the woman took up her infant from the cradle where it lay playing in perfect health, and gave it the breast.
Most persons have heard of the idea which attributes the occurrence of jaundice to some strong disgust experienced by the subject of the affection, which, as is well-known, simply consists in suppression of the bile or secretion of the liver-although by physicians jaundice is viewed rather as a symptom of other affections that as constituting of itself a primary disease. The bile was accounted in the early days of physiological research one of the humors, wherein was stored black care, or that green and yellow melancholy" of which Shakespeare speaks. The same ideas which referred the passions to the various organs of the body-and which still figuratively survive when we speak of "a fit of the spleen," of the meditative spleen" of Wordsworth, or of the
fear and rage possess a similar influence Hunter's words, that "there is not a on the bodily secretions by inducing natural action in the body, whether ina deleterious or even deadly effect. A voluntary or voluntary, that may not be puppy has been known to die in convul- influenced by the peculiar state of the sions on sucking its mother after she had mind at the time, may be viewed in been engaged in a fierce dispute with the light of a simple truism. And another dog. The effects of fear in sagely Burton delivers himself in his modifying bodily processes have been "Anatomy of Melancholy," when he exemplified in the case of the heart's remarks, that "Imagination is the mediaction; but they receive an equally in- um defens of passions, by whose means teresting illustration in the disturbing in- they work and produce many times profluence of fear upon the secretion of the digious effects; and as the phantasie is saliva. As the mouth "waters" when more or less intended or remitted and the dainty morsel is perceived or even their humors disposed, so do perturbathought of, so the opposite effect may tions move more or less, and make be induced under the influence of a ner- deeper impression." vous dread and fear. No better illustration of this last assertion is to be found than in the case of the Indian method of discovering a thief. The priest who presides at the ordeal in question necessarily, by his mere presence, induces in the mind a superstitious horror of discovery. The servants in the household being seated and duly warned of the infallibility of the procedure, are furnished each with a mouthful of rice, which they are requested to retain in the mouth for a given time. At the expiry of the period the rice is examined, when it is generally found that in the case of the guilty person the morsel is as dry as when he received it, the rice of his fellows being duly moistened. The suspension of secretion under the influence of fear may not be of universal Occurrence. It is conceivable and prob-heart" as base, wicked, grateful or able that a person of strong will, even although laboring under the conviction of conscious guilt, might successfully pass through the ordeal; but the essential hold of the operator is in the influence of fear and the terror of detection by a process which the guilty person equally with his innocent neighbors believes to be all-powerful for the designed end. The feeling of conscious innocence would tend to promote the flow of saliva, while that of guilt would produce the opposite effect. Thus the common complaint of feeling out of sorts" under the influence of worry and vexation, is but an illustration, drawn from every-day existence, of the effects of mental irritation upon the ordinary functions of the body, and an impaired digestion may thus appear as the true product of a mental worry. John
glad-assigned to the bile no very au-
referring anger to the liver as its seat. Even Solomon makes misguided passion to be typified by the dart, which strikes through the liver of the unguarded subject; and Jeremiah similarly conveys the idea of intense grief in the metaphor, "my liver is poured upon the earth." These ideas have long since been exploded; but there remains with us the equally curious notion that the influence of the mind upon the body may extend so far as to produce the