Physiological Researches on Life and Death

by Xavier Bichat

We may conclude that the brain, the central organ of the animal life, is the centre of whatever relates to the understanding. I might here proceed to speak of its volume in man, and in animals, whose intelligence appears to decrease in proportion as the facial angle is diminished, and expatiate upon the different alterations of which the cerebral cavity is the seat, as well as on the disorders of the intellectual functions arising thence. But these things are all of them well enough understood. Let us pass to that order of phenomena, which though as foreign as the preceding to the ideas which we form of material appearances, are elsewhere seated.

II. Whatever relates to the passions belongs to the organic life.

My present object is not to consider the passions metaphysically. It little matters, whether they be all of them the modifications of a single passion, or dependent each of them upon a separate principle. We shall only remark, that many physicians in discussing their influence on the organic phenomena, have not sufficiently distinguished them from the sensations; the latter are the occasion of the passions, but differ from them widely.

It is true that anger, joy, and sorrow, would not affect us, were we not to find their causes in our connexions with external objects. It is true also, that the senses are the agents of these relations, that they communicate the causes of the passions, but in this they act as simple conductors only, and have nothing in common with the affections, which they produce; for sensation of every kind has its centre in the brain, sensation of every kind supposing impression and perception. If the action of the brain be suspended, sensation ceases; on the contrary, the brain is never affected by the passions; their seat is in the organs of the internal life.[15]

It is undoubtedly surprising that the passions, essentially as they enter into our relations with the beings which are placed about us, that modifying as they do at every moment these relations, that animating, enlarging, and exalting the phenomena of the animal life, which without them would be nothing but a cold series of intellectual movements; it is astonishing, I say, that the passions should neither have their end, nor beginning in the organs of this life, but on the contrary, that the parts which serve for the internal functions, should be constantly affected by them, and even occasion them according to the state in which they are found. Such notwithstanding is the result of the strictest observation.

I shall first observe, that the effect of every kind of passion is at all times to produce some change in the organic life. Anger accelerates the circulation of the blood, it multiplies the efforts of the heart. The passion of joy has not indeed so marked an influence upon the circulation, but alters it notwithstanding, and carries it lightly towards the skin. Terror acts inversely; this passion being characterized by a feebleness in the vascular system, a feebleness, which in hindering the blood from arriving at the capillary vessels, occasions the paleness which at such time is so particularly remarked. The effects of sadness and sorrow are nearly analogous.

So great indeed is the effect which the passions occasion upon the organs of the circulation, as even to arrest them altogether in their functions, where the affection is very powerful. In this way is syncope produced, for the primitive seat of syncope is always, as I shall soon prove it to be, in the heart, and not in the brain. In this the latter organ ceases to act, only because it ceases to receive the excitant necessary to its action. Hence also may happen death itself, the sometimes sudden effect of extreme emotion, whether such emotion as in anger so far exalts and exhausts the powers of the circulation, as not to leave them any further excitability, or whether as in the death occasioned by excessive grief, the powers at once excessively debilitated, are no longer capable of returning to their usual condition.

If the total and instantaneous cessation of the circulation be not occasioned by this debility, a variety of lesions in the blood vessels may be, notwithstanding, the effect of it. Desault has remarked that diseases of the heart, and aneurisms of the aorta, were augmented in number during the revolution, in proportion to the evils which it produced.

Nor does respiration depend less immediately upon the passions; that oppression, that anxiety, and sense of suffocation, which is the sudden effect of profound sorrow, must imply in the lungs a remarkable change and sudden alteration. In that very long series of chronic or acute affections, the sad attribute of the pulmonary system, must we not often look to the passions to find the principle of the disease?