The Expression of Emotion in Man and Animals - Charles Darwin (an ebook reader TXT) 📗

changed and this peculiar expression vanished. Again, after a little boy had been vaccinated, which made him scream and cry violently, the surgeon gave him an orange brought for the purpose, and this pleased the child much; as he stopped crying all the characteristic movements were observed, including the formation of rectangular wrinkles in the middle of the forehead.

Lastly, I met on the road a little girl three or four years old, who had been frightened by a dog, and when I asked her what was the matter, she stopped whimpering, and her eyebrows instantly became oblique to an extraordinary degree.

 

[5] Mecanisme de la Phys. Humaine, Album, p. 15.

 

Here then, as I cannot doubt, we have the key to the problem why the central fasciae of the frontal muscle and the muscles round the eyes contract in opposition to each other under the influence of grief;—whether their contraction be prolonged, as with the melancholic insane, or momentary, from some trifling cause of distress. We have all of us, as infants, repeatedly contracted our orbicular, corrugator, and pyramidal muscles, in order to protect our eyes whilst screaming; our progenitors before us have done the same during many generations; and though with advancing years we easily prevent, when feeling distressed, the utterance of screams, we cannot from long habit always prevent a slight contraction of the above-named muscles; nor indeed do we observe their contraction in ourselves, or attempt to stop it, if slight. But the pyramidal muscles seem to be less under the command of the will than the other related muscles; and if they be well developed, their contraction can be checked only by the antagonistic contraction of the central fasciae of the frontal muscle.

The result which necessarily follows, if these fasciae contract energetically, is the oblique drawing up of the eyebrows, the puckering of their inner ends, and the formation of rectangular furrows on the middle of the forehead.

As children and women cry much more freely than men, and as grown-up persons of both sexes rarely weep except from mental distress, we can understand why the grief-muscles are more frequently seen in action, as I believe to be the case, with children and women than with men; and with adults of both sexes from mental distress alone. In some of the cases before recorded, as in that of the poor Dhangar woman and of the Hindustani man, the action of the grief-muscles was quickly followed by bitter weeping. In all cases of distress, whether great or small, our brains tend through long habit to send an order to certain muscles to contract, as if we were still infants on the point of screaming out; but this order we, by the wondrous power of the will, and through habit, are able partially to counteract; although this is effected unconsciously, as far as the means of counteraction are concerned.

 

On the depression of the corners of the mouth.—This action is effected by the depressores anguili oris (see letter K in figs.

1 and 2). The fibres of this muscle diverge downwards, with the upper convergent ends attached round the angles of the mouth, and to the lower lip a little way within the angles.[6] Some of the fibres appear to be antagonistic to the great zygomatic muscle, and others to the several muscles running to the outer part of the upper lip.

The contraction of this muscle draws downwards and outwards the corners of the mouth, including the outer part of the upper lip, and even in a slight degree the wings of the nostrils. When the mouth is closed and this muscle acts, the commissure or line of junction of the two lips forms a curved line with the concavity downwards,[7] and the lips themselves are generally somewhat protruded, especially the lower one.

The mouth in this state is well represented in the two photographs (Plate II., figs. 6 and 7) by Mr. Rejlander. The upper boy (fig. 6) had just stopped crying, after receiving a slap on the face from another boy; and the right moment was seized for photographing him.

 

[6] Henle, Handbuch der Anat. des Menschen, 1858, B. i. s. 148, figs.

68 and 69.

 

[7] See the account of the action of this muscle by Dr. Duchenne, `Mecanisme de la Physionomie Humaine, Album (1862), viii. p. 34.

 

The expression of low spirits, grief or dejection, due to the contraction of this muscle has been noticed by every one who has written on the subject.

To say that a person “is down in the mouth,” is synonymous with saying that he is out of spirits. The depression of the corners may often be seen, as already stated on the authority of Dr. Crichton Browne and Mr. Nicol, with the melancholic insane, and was well exhibited in some photographs sent to me by the former gentleman, of patients with a strong tendency to suicide.

It has been observed with men belonging to various races, namely with Hindoos, the dark hill-tribes of India, Malays, and, as the Rev. Mr. Hagenauer informs me, with the aborigines of Australia.

 

When infants scream they firmly contract the muscles round their eyes, and this draws up the upper lip; and as they have to keep their mouths widely open, the depressor muscles running to the corners are likewise brought into strong action.

This generally, but not invariably, causes a slight angular bend in the lower lip on both sides, near the corners of the mouth.

The result of the upper and lower lip being thus acted on is that the mouth assumes a squarish outline. The contraction of the depressor muscle is best seen in infants when not screaming violently, and especially just before they begin, or when they cease to scream.

Their little faces then acquire an extremely piteous expression, as I continually observed with my own infants between the ages of about six weeks and two or three months. Sometimes, when they are struggling against a crying-fit, the outline of the mouth is curved in so exaggerated a manner as to be like a horseshoe; and the expression of misery then becomes a ludicrous caricature.

 

The explanation of the contraction of this muscle, under the influence of low spirits or dejection, apparently follows from the same general principles as in the case of the obliquity of the eyebrows.

Dr. Duchenne informs me that he concludes from his observations, now prolonged during many years, that this is one of the facial muscles which is least under the control of the will. This fact may indeed be inferred from what has just been stated with respect to infants when doubtfully beginning to cry, or endeavouring to stop crying; for they then generally command all the other facial muscles more effectually than they do the depressors of the corners of the mouth.

Two excellent observers who had no theory on the subject, one of them a surgeon, carefully watched for me some older children and women as with some opposed struggling they very gradually approached the point of bursting out into tears; and both observers felt sure that the depressors began to act before any of the other muscles.

Now as the depressors have been repeatedly brought into strong action during infancy in many generations, nerve-force will tend to flow, on the principle of long associated habit, to these muscles as well as to various other facial muscles, whenever in after life even a slight feeling of distress is experienced.

But as the depressors are somewhat less under the control of the will than most of the other muscles, we might expect that they would often slightly contract, whilst the others remained passive.

It is remarkable how small a depression of the corners of the mouth gives to the countenance an expression of low spirits or dejection, so that an extremely slight contraction of these muscles would be sufficient to betray this state of mind.

 

I may here mention a trifling observation, as it will serve to sum up our present subject. An old lady with a comfortable but absorbed expression sat nearly opposite to me in a railway carriage.

Whilst I was looking at her, I saw that her depressores anguli oris became very slightly, yet decidedly, contracted; but as her countenance remained as placid as ever, I reflected how meaningless was this contraction, and how easily one might be deceived.

The thought had hardly occurred to me when I saw that her eyes suddenly became suffused with tears almost to overflowing, and her whole countenance fell. There could now be no doubt that some painful recollection, perhaps that of a long-lost child, was passing through her mind. As soon as her sensorium was thus affected, certain nerve-cells from long habit instantly transmitted an order to all the respiratory muscles, and to those round the mouth, to prepare for a fit of crying.

But the order was countermanded by the will, or rather by a later acquired habit, and all the muscles were obedient, excepting in a slight degree the depressores anguli oris.

The mouth was not even opened; the respiration was not hurried; and no muscle was affected except those which draw down the corners of the mouth.

 

As soon as the mouth of this lady began, involuntarily and unconsciously on her part, to assume the proper form for a crying-fit, we may feel almost sure that some nerve-influence would have been transmitted through the long accustomed channels to the various respiratory muscles, as well as to those round the eyes, and to the vasomotor centre which governs the supply of blood sent to the lacrymal glands.

Of this latter fact we have indeed clear evidence in her eyes becoming slightly suffused with tears; and we can understand this, as the lacrymal glands are less under the control of the will than the facial muscles.

No doubt there existed at the same time some tendency in the muscles round the eyes at contract, as if for the sake of protecting them from being gorged with blood, but this contraction was completely overmastered, and her brow remained unruffled. Had the pyramidal, corrugator, and orbicular muscles been as little obedient to the will, as they are in many persons, they would have been slightly acted on; and then the central fasciae of the frontal muscle would have contracted in antagonism, and her eyebrows would have become oblique, with rectangular furrows on her forehead.

Her countenance would then have expressed still more plainly than it did a state of dejection, or rather one of grief.

 

Through steps such as these we can understand how it is, that as soon as some melancholy thought passes through the brain, there occurs a just perceptible drawing down of the corners of the mouth, or a slight raising up of the inner ends of the eyebrows, or both movements combined, and immediately afterwards a slight suffusion of tears. A thrill of nerve-force is transmitted along several habitual channels, and produces an effect on any point where the will has not acquired through long habit much power of interference.

The above actions may be considered as rudimental vestiges of the screaming-fits, which are so frequent and prolonged during infancy.

In this case, as well as in many others, the links are indeed wonderful which connect cause and effect in giving rise to various expressions on the human countenance; and they explain to us the meaning of certain movements, which we involuntarily and unconsciously perform, whenever certain transitory emotions pass through our minds.

CHAPTER VIII.

 

Joy, HIGH SPIRITS, LOVE, TENDER FEELINGS, DEVOTION.

 

Laughter primarily the expression of joy—Ludicrous ideas—

Movements of the features during laughter—Nature of the sound produced—The secretion of tears during loud laughter—

Gradation from loud laughter to gentle smiling—High spirits—

The expression of love—Tender feelings—Devotion.

 

JOY, when intense, leads to various purposeless movements—

to dancing