Fear

by A. Mosso

III

When one considers as a whole the symptoms by which fear reveals itself, one might almost think that it was a product of heredity and selection. Animals that are easily frightened, a disciple of Darwin would say, are those which can more easily avoid danger and save themselves; these produce young, and perpetuate their timidity in their posterity. But we know that the phenomena of fear are the morbid exaggeration of physiological facts. Animals cannot become continually more timorous by means of hereditary transmission; the necessity of struggling brings other faculties than those of flight and fear into play, and effect the preservation of the species in another way. Our organism is not such a perfect machine as to be able to resist or adapt itself to all conditions of environment; there are inevitable necessities against which selection is of no avail.

In my opinion, although we may accept the principle of Spencer and Darwin as an explanation of many things, we yet cannot extend it to all phenomena. Spencer and Darwin were not physiologists enough; in their studies of the emotions they did not sufficiently seek the causes of the phenomena observed by them in the functions of the organism. There are, so to speak, hierarchies in the parts composing our machine, for all functions are not equally important. But in the whole of the vital economy one notices the preponderance and supremacy of the blood-vessels. It is so indispensable that the organism should profit by all the material procurable for the nutrition of the nerve-centres, that the circulation of the blood in all parts (therefore in the eye also) is subordinated to this prime object.

In this way it seems to me the fact may be explained that the blood-vessels of the iris contract during strong emotions, notwithstanding that this produces excessive dilatation of the pupil, and that the back of the eye becomes anæmic, although this contraction of the vessels of the retina is disadvantageous to distinct vision.

We often hear persons, speaking of some great fright, say: 'I was like one struck blind, I could see nothing.’ Travellers tell of serpents blind with fear, that bit the shadows and branches of the trees, blunting their teeth and shedding their poison fruitlessly.

Darwin maintains that there are two distinct causes for the frown which every little difficulty in a train of thought produces. One is very similar to that propounded by Spencer, of which we have already spoken; the other runs as follows: 'The earliest and almost sole expression seen during the first days of infancy, and then often exhibited, is that displayed during the act of screaming; and screaming is excited, both at first and for some time afterwards, by every distressing or displeasing sensation and emotion,—by hunger, pain, anger, jealousy, fear, &c. At such times the muscles round the eyes are strongly contracted; and this, as I believe, explains to a large extent the act of frowning during the remainder of our lives.’[23]

This explanation does not seem to me satisfactory, because it only pushes the question further back, and we must still ask: But why does the child frown when it cries? But, indeed, it suffices to render Darwin’s hypothesis improbable, if we call to mind that new-born children frown before they shed a single tear.

The following is the explanation which I offer of this phenomenon.

When we look intently at an object, we must contract all internal and external muscles of the eye. This is indispensable in order to effect the adjustment by which we modify the curvature of the lens in the interior of the eye; that is to say, we alter the lens according to the distance, in the same way as anyone looking through a telescope adjusts it by lengthening or shortening the tube. We have already seen that the pupil must contract when we contemplate an object close to us; thus we cannot direct our gaze towards our nose without a contraction of the pupil.

The most important movement of the external muscles of the eye is that by means of which we produce a convergence of the visual rays from both eyes on the object of attention. Thus, whereas the two eyes are parallel when we are absent-minded or gazing into distance, they converge when fixed on an object near us, as the hands would meet in order to take hold of it. All these movements are effected by a single nerve, called the motor-oculi, between which and the facial nerve there is a certain sympathy, as may be seen in the unconscious movement of the eyelids and forehead when we exercise the eye. And vice versa, when we close the lids, we move the eyeball without intending to do so. We may convince ourselves of this if we hold one eye shut with a finger and then close the lid of the other; immediately we feel the eyeball under the finger turn downwards.

The muscles of the eye contract also when we exert ourselves; for instance, if we try by night to look at a small distant light, at the same time lifting a heavy weight, or exerting ourselves in some other way, we see the light double, owing to the involuntary convergence of the eyes. I have photographed several persons during physical exertion, and many of them have quite the appearance of suffering, so pronounced is the contraction of the muscles of the forehead, although it was quite unnecessary. The arrangements of our organism are such that the energy, the tension of the nervous system diffuses itself in various directions, without the possibility, in certain cases, of restricting its influence to limited muscular groups. Thus, if we try to move the ear, the muscles which raise the corner of the mouth also contract; if we merely tell someone to close his eyes, we see the other facial muscles move, often causing involuntary grimaces. Again, we cannot move one eye to the right and the other to the left. Very few can turn the pupil upwards without raising the eyelids, or move the eyebrows separately. All this is due to the difficulty of localising the action of the will in the nervous fibres leading only to certain muscles; several groups of fibres seem always drawn simultaneously into the sphere of action, except when there has been much practice in discerning and selecting the fibres which shall accomplish an isolated movement, or when an intentional effort is made, which, however, is a matter of much difficulty.

When animals look attentively at some object, they turn their ears towards it. This movement, which they make in order to collect the sounds, must be preceded by a contraction of the muscles of the forehead and of those serving to turn the auricle of the ear. It is very probable that these movements, noticeable also in monkeys, have been preserved in man, although in attention he no longer moves the ears but only the muscles of the forehead.

In our nature psychic processes are so closely connected with their external sensory manifestations that it is impossible to check the manifestation of nervous activity in the muscles whenever the ideas appear to which these external movements stand in a permanent relation, even when this external communication is quite unnecessary. Thus we see that a man lost in thought gesticulates, making a hundred involuntary movements, and sometimes speaks, although no one is with him to whom he need communicate his ideas. And so it happens that we reproduce the characteristic movements of attention in forehead and eye whenever, in the various contingencies of life or in the development of ideas, an obstacle hinders the progress of thought. As soon as we begin any work which demands greater force of attention and reflection, we immediately and involuntarily put into action the mechanism of forehead and eye, which has always been made use of in intently scrutinising objects.