MISCELLANEOUS PAPERS ON SUBJECTS RELATING TO DISORDERS OF THE HEART.
MISCELLANEOUS PAPERS.
THE INFLUENCE OF THE MIND OVER THE HEART.
THE object of this paper is twofold: First. To show the powerful influence which the mind can and does exert over the heart, and the manner in which such influence is exerted.
Secondly. The results which may be brought about upon the normal conditions of the heart by such influence; and their value from a medico-legal and therapeutic point of view.
We will first inquire how the mind can affect the heart; or, in other words, through what nerve-channels the intellect, the will, and the emotions can affect that important organ.
The heart is supplied with nerves by the pneumogastric and the sympathetic; but we find it impossible to make satisfactory experiments with the nerves in connection with the purely emotional influences.
We are obliged to depend mainly on negative testimony, viz., the effect produced upon the heart by irritation and by division of these nerves. Even here, unfortunately, we are met by so much contradictory evidence that it really seems hopeless to arrive at any definite conclusion.
Claude Bernard, Weber, Valentine, Schiff, and Lockhart Clark disagree in many essential particulars relating to the effects of division or irritation of the pneumogastrics.
The majority of evidence, however, is in favor of the conclusion that the pneumogastrics, pure and simple, contain motor fibres, and that, through the cardiac branches, they effect the motions of the heart.
The pneumogastric may contain sensory fibres also, and may, therefore, be a compound nerve from its origin.
With regard to the influence of the sympathetic, Carpenter found that pressure on the great cardiac sympathetic nerve checks the heart’s pulsations from four to six beats, causing fearful anxiety and pain; while Weber found that stimuli conveyed through this nerve accelerated the movements of the heart.
These and other facts leave no room to doubt that the sympathetic nerves are also concerned in the motions of the heart.
Now the question is whether the emotions act through them or the pneumogastrics, or both, when accelerating or retarding the movements of the heart.
As to the sympathetic nerves of the heart, Moleschott’s experiments demonstrated that the same phenomena occurred as in the case of the vagi, when excited mildy or strongly by galvanism, and he concludes that these two sets of nerves exercise the same influence upon this viscus.
It appears fair, therefore, to conclude that the emotions act upon the heart both through the vagi and the sympathetic. Their modus operandi now accelerating, now retarding its action would seem to derive illustration from these and similar experiments.
If we were to substitute emotion for the stimulus applied by Moleschott to the nerves proceeding to the heart, we can well understand how the former should produce the various and opposite disturbances of this organ, including spasm and paralysis, with which, we are familiar. First, as a feeble or moderate stimulus of the vagus (whether electric or otherwise) causes a considerable rise in the pulse, so does an emotion which is not excessive in character. Secondly, as an increased stimulus gradually retards the action of the heart, while a very powerful one immediately arrests it from the fatigue which succeeds stimulus, just so, we can well conceive, a violent emotion would act. Thirdly, the fatigue may be gradually recovered from and the heart’s action restored to its normal frequency and force.
The ganglia of the heart appear to act in the way of communicating the condition of one of the four nerves supplying the heart to the other three. In regard to the emotional stimuli, however, it seems impossible to decide whether one is more influenced than another, and in view of Professor Moleschott’s experiments, it is evident that the emotions may act in precisely the same way through either the vagi or sympathetic.
We may be allowed to surmise that the ganglia and the fourfold supply of nerves to this organ are designed to lessen its liability to fatal spasm and paralysis by emotion.
“The heart,” observes Moleschott, “is animated by four very excitable nerves, which may be easily over-excited; these four nerves, two vagi and two sympathetic, have a peculiar consensus, which is no doubt due to the action of the ganglia of the heart, so that the state of irritation or over-excitement of one is conveyed to the other three; but it is impossible to permanently exhaust the other three by the overexcitation of one nerve singly, as stimulants which would be powerful enough to effect this, would soon kill the excited portion of the one nerve, and therefore lose their effect upon the other three; such an effect being only possible as long as the nerve acted upon retains part at least of its excitability.”
This conclusion accords with the opinion of Kirkes and Paget, that the cardiac branches of the pneumogastric are one, through not the sole channel through which the influence of emotion is transmitted to this organ, and with that of Dr. Carpenter, already cited; and it does not contradict the judgment expressed by him elsewhere, that the sympathetic constitutes the channel through which the passions produce palpitation of the heart, or Dr. Baly’s statement, that the disturbed action of the heart during emotion is a remarkable instance of the influence of the passions over movements of organs supplied by the sympathetic.
Since Moleschott’s experiments, those of MM. Cyon and Ludwig indicate the existence of accelerator and depressor nerves of the heart, the former emerging from the cord with the third branch of the inferior cervical ganglion, and the latter arising, in rabbits, from the pneumogastric and superior laryngeal nerves.
Bernard, it is stated, adopted this view, and held that the heart, with this sensory depressor nerve, is able to regulate its volume according to circumstances, by exerting a reflex action on the general circulation.
If the inhibitory view of the pneumogastric nerve be established, we must, in attempting to explain the injurious mode of action of certain emotional states upon the heart, suppose that the normal control which is being constantly exercised by this nerve is, under excessive emotion, so intensified under increased stimulation at its origin in the medulla oblongata, that the pulsations of the organ are partially or wholly arrested. A provision by which the heart is prevented sending more blood to an organ already too vascular from emotional excitement, may thus cause death.
It seems, however, that as long as physiologists differ so widely as to the functions of the nerves supplying the heart, it is impossible to determine the exact manner in which the emotions influence this organ.
The general conclusion is, that it is through the acknowledged sympathetic and probably through the pneumogastric by reflex action, when excited centrally by certain emotional states, just as it is alleged to do from the state of the heart at the periphery, or, if Moleschott’s views be adopted, directly through the motor fibres of this nerve.
In order to be methodical and give a more clear and comprehensive understanding, we will take up the various functions of the mind, as the intellect, the will, and the emotions.
THE INTELLECT.
The influence of the intellect upon the heart is similar to that exercised over voluntary muscles.
The direction of thought to the heart has very generally an embarrassing influence on its regular action.
Sir Henry Holland says: “There is cause to believe the action of the heart is often quickened or otherwise disturbed by the mere centering the consciousness on it, without any emotion or anxiety.” On occasions where its beats are audible, observation will give proof of this, or the physician can very often infer it while feeling the pulse; and where there is liability to irregular pulsation such action is seemingly brought on or increased by the effort of attention, even though no obvious emotion be present.
I have observed this phenomenon, in my own practice, in hysterical women, who imagine they have heart disease. In these cases a morbid attention to the action of the heart would bring on palpitation and irregular action. Upon the removal of all anxiety by a decided assertion from me, after a careful physical examination, that the heart was not discussed, it would quickly resume its normal action.
From the same cause medical students, when their thoughts are directed by their studies to this organ, are frequently sufferers from its disturbed action. Anxiety, no doubt, comes in here to aggravate the disorder, and will be referred to again under emotions. Peter Frank himself, even in advanced life, while devoting especially attention to the subject of heart disease, during the preparation of his lectures, was attacked with severe palpitations, accompanied by an intermittent pulse, and felt certain that he was affected with an aneurism. The symptoms did not cease till some time after the completion of his labors, and after he had enjoyed the relaxation and diversion of a journey. In fact, it is quite a common remark that medical men often die from a disease that they have made a special study during life.
Hale wrote Lectures On Diseases Of The Heart, Materia medica and special therapeutics of the new remedies Volume 1, Materia Medica And Special Therapeutics Of The New Remedies Volume 2, Saw Palmetto: (Sabal Serrulata. Serenoa Serrulata), The Medical, Surgical, and Hygienic Treatment of Diseases of Women, New Remedies: Their Pathogenetic Effects and Therapeutic Application, Ilex Cassine : the aboriginal North American tea, Repertory to the New Remedies with Charles Porter Hart, The Characteristics of the New Remedies, Materia Medica and Special Therapeutics of the New Remedies, The Practice of Medicine, Homoeopathic Materia Medica of the New Remedies: Their Botanical Description etc.