Wednesday 20 December 2006

Darwin on Tears

Darwin on Tears



Just been re-reading Darwin on emotions

http://pages.britishlibrary.net/charles.darwin3/expression/expression06.htm

which is very interesting. As ever, he looked at observing what is happening first, and is ingenuous in his use of existing technology to do this (photos are on the attached site).

Here I shall almost confine myself to weeping or crying, more especially in children. Infants, when suffering even slight pain, moderate hunger, or discomfort, utter violent and prolonged screams. Whilst thus screaming their eyes are firmly closed, so that the skin round them is wrinkled, and the forehead contracted into a frown. The mouth is widely opened with the lips retracted in a peculiar manner, which causes it to assume a squarish form; the gums or teeth being more or less exposed. The breath is inhaled almost spasmodically. It is easy to observe infants whilst screaming; but I have found photographs made by the instantaneous process the best means for observation, as allowing more deliberation. I have collected twelve, most of them made purposely for me; and they all exhibit the same general characteristics. I have, therefore, had six of them1 (Plate I.) reproduced by the heliotype process.

He also made the observation, which he then tested that very young infants in fact do not shed tears or weep; which he says is "well known", although I had not come across it in any modern baby books; but then Darwin is both observing, and looking at the evolutionary background. From this he deduces that weeping and crying is an acquired or learned technique; it is something done rather than something automatic (which is not, of course, to say that it cannot become automatic like other habits).

Infants whilst young do not shed tears or weep, as is well known to nurses and medical men. This circumstance is not exclusively due to the lacrymal glands being as yet incapable of secreting tears. I first noticed this fact from having accidentally brushed with the cuff of my coat the open eye of one of my infants, when seventy-seven days old, causing this eye to water freely; and though the child screamed violently, the other eye remained dry, or was only slightly suffused with tears. A similar slight effusion occurred ten days previously in both eyes during a screaming-fit. The tears did not run over the eyelids and roll down the cheeks of this child, whilst screaming badly, when 122 days old. This first happened 17 days later, at the age of 139 days. A few other children have been observed for me, and the period of free weeping appears to be very variable. In one case, the eyes became slightly suffused at the age of only 20 days; in another, at 62 days. With two other children, the tears did not run down the face at the ages of 84 and 110 days; but in a third child they did run down at the age of 104 days. In one instance, as I was positively assured, tears ran down at the unusually early age of 42 days. It would appear as if the lacrymal glands required some practice in the individual before they are easily excited into action, in somewhat the same manner as various inherited consensual movements and tastes require some exercise before they are fixed and perfected. This is all the more likely with a habit like weeping, which must have been acquired since the period when man branched off from the common progenitor of the genus Homo and of the non-weeping anthropomorphous apes.
The fact of tears not being shed at a very early age from pain or any mental emotion is remarkable, as, later in life, no expression is more general or more strongly marked than weeping. When the habit has once been acquired by an infant, it expresses in the clearest manner suffering of all kinds, both bodily pain and mental distress, even though accompanied by other emotions, such as fear or rage. The character of the crying, however, changes at a very early age, as I noticed in my own infants,—the passionate cry differing from that of grief. A lady informs me that her child, nine months old, when in a passion screams loudly, but does not weep; tears, however, are shed when she is punished by her chair being turned with its back to the table. This difference may perhaps be attributed to weeping being restrained, as we shall immediately see, at a more advanced age, under most circumstances excepting grief; and to the influence of such restraint being transmitted to an earlier period of life, than that at which it was first practised.

Next, he looks at adults, with a very broad outlook, i.e not restricting himself to Victorian London. Would that Freud had done the same when creating his ideas rather than just !

With adults, especially of the male sex, weeping soon ceases to be caused by, or to express, bodily pain. This may be accounted for by its being thought weak and unmanly by men, both of civilized and barbarous races, to exhibit bodily pain by any outward sign. With this exception, savages weep copiously from very slight causes, of which fact Sir J. Lubbock has collected instances. A New Zealand chief "cried like a child because the sailors spoilt his favourite cloak by powdering it with flour." I saw in Tierra del Fuego a native who had lately lost a brother, and who alternately cried with hysterical violence, and laughed heartily at anything which amused him. With the civilized nations of Europe there is also much difference in the frequency of weeping. Englishmen rarely cry, except under the pressure of the acutest grief; whereas in some parts of the Continent the men shed tears much more readily and freely.

After this, his examination looks at the pathological cases, to see what sort of crying is going on there. He notices that crying is far more common, and sometimes for almost no visible cause, or for the oddest causes (e.g. the case of the eyebrows). He is of course using the terminology of his day (insane etc), but also notes that certain physiological conditions can also cause or promote crying; in other words, it can be an involuntary effect.

The insane notoriously give way to all their emotions with little or no restraint; and I am informed by Dr. J. Crichton Browne, that nothing is more characteristic of simple melancholia, even in the male sex, than a tendency to weep on the slightest occasions, or from no cause. They also weep disproportionately on the occurrence of any real cause of grief. The length of time during which some patients weep is astonishing, as well as the amount of tears which they shed. One melancholic girl wept for a whole day, and afterwards confessed to Dr. Browne, that it was because she remembered that she had once shaved off her eyebrows to promote their growth. Many patients in the asylum sit for a long time rocking themselves backwards and forwards; "and if spoken to, they stop their movements, purse up their eyes, depress the corners of the mouth, and burst out crying." In some of these cases, the being spoken to or kindly greeted appears to suggest some fanciful and sorrowful notion; but in other cases an effort of any kind excites weeping, independently of any sorrowful idea. Patients suffering from acute mania likewise have paroxysms of violent crying or blubbering, in the midst of their incoherent ravings. We must not, however, lay too much stress on the copious shedding of tears by the insane, as being due to the lack of all restraint; for certain brain-diseases, as hemiplegia, brain-wasting, and senile decay, have a special tendency to induce weeping. Weeping is common in the insane, even after a complete state of fatuity has been reached and the power of speech lost.

Darwin then sums up what he perceives weeping to be the expression of, but also notes that the degree to which people weep can be altered by themselves, either with restraint, or by learning to increase tears; the weeping for the dead, is in fact, something which is not just seen in his case study; it was well known in past cultures where professional mourners could weep "on demand", but convincingly.

Weeping seems to be the primary and natural expression, as we see in children, of suffering of any kind, whether bodily pain short of extreme agony, or mental distress. But the foregoing facts and common experience show us that a frequently repeated effort to restrain weeping, in association with certain states of the mind, does much in checking the habit. On the other hand, it appears that the power of weeping can be increased through habit; thus the Rev. R. Taylor, who long resided in New Zealand, asserts that the women can voluntarily shed tears in abundance; they meet for this purpose to mourn for the dead, and they take pride in crying "in the most affecting manner."

So - having examined a wide variety of different evidence (and I have only cited some) - now he comes to look at how to construct a theory for understanding weeping, and he starts from the physiological, seeing tears resulting from distress, or laughter (which he notes is also common to all human beings), or even a coughing fit:

Cause of the secretion of tears.—It is an important fact which must be considered in any theory of the secretion of tears from the mind being affected, that whenever the muscles round the eyes are strongly and involuntarily contracted in order to compress the blood-vessels and thus to protect the eyes, tears are secreted, often in sufficient abundance to roll down the cheeks. This occurs under the most opposite emotions, and under no emotion at all. The sole exception, and this is only a partial one, to the existence of a relation between the involuntary and strong contraction of these muscles and the secretion of tears, is that of young infants, who, whilst screaming violently with their eyelids firmly closed, do not commonly weep until they have attained the age of from two to three or four months. Their eyes, however, become suffused with tears at a much earlier age. It would appear, as already remarked, that the lacrymal glands do not, from the want of practice or some other cause, come to full functional activity at a very early period of life. With children at a somewhat later age, crying out or wailing from any distress is so regularly accompanied by the shedding of tears, that weeping and crying are synonymous terms.
Under the opposite emotion of great joy or amusement, as long as laughter is moderate there is hardly any contraction of the muscles round the eyes, so that there is no frowning; but when peals of loud laughter are uttered, with rapid and violent spasmodic expirations, tears stream down the face. I have more than once noticed the face of a person, after a paroxysm of violent laughter, and I could see that the orbicular muscles and those running to the upper lip were still partially contracted, which together with the tear-stained cheeks gave to the upper half of the face an expression not to be distinguished from that of a child still blubbering from grief. The fact of tears streaming down the face during violent laughter is common to all the races of mankind, as we shall see in a future chapter.
In violent coughing especially when a person is half-choked, the face becomes purple, the veins distended, the orbicular muscles strongly contracted, and tears run down the cheeks. Even after a fit of ordinary coughing, almost every one has to wipe his eyes. In violent vomiting or retching, as I have myself experienced and seen in others, the orbicular muscles are strongly contracted, and tears sometimes flow freely down the cheeks.

Now he broadens his scope further to look at other animals, but finds extremely few cases:

I was anxious to ascertain whether there existed in any of the lower animals a similar relation between the contraction of the orbicular muscles during violent expiration and the secretion of tears; but there are very few animals which contract these muscles in a prolonged manner, or which shed tears.

So now he comes to the evolutionary and biological background of tears. Why did crying and tears develop? What was their main function?

It is difficult to conjecture how many reflex actions have originated, but, in relation to the present case of the affection of the lacrymal glands through irritation of the surface of the eye, it may be worth remarking that, as soon as some primordial form became semi-terrestrial in its habits, and was liable to get particles of dust into its eyes, if these were not washed out they would cause much irritation; and on the principle of the radiation of nerve-force to adjoining nerve-cells, the lacrymal glands would be stimulated to secretion. As this would often recur, and as nerve-force readily passes along accustomed channels, a slight irritation would ultimately suffice to cause a free secretion of tears.

So Darwin sees tears and crying as a development which has evolved from the physiology of crying out (for a variety of reasons, e.g. suffering, calling parents, and relieving pain by bodily movements - which is part of the same evolutionary heritage which we share with other animals. Our biological makeup, however, causes the use of tears as an eye-cleaning mechanism to be incidentally triggered by these physiological changes, and this incidental use of tears (an exaption, in evolutionary biology) as a means of relieving suffering is not purely an involutantary act (although it remains that as well in addition to new uses, which we should not forget), but can also be controlled (either to stop tears, or to cry on demand).

To sum up this chapter, weeping is probably the result of some such chain of events as follows. Children, when wanting food or suffering in any way, cry out loudly, like the young of most other animals, partly as a call to their parents for aid, and partly from any great exertion serving relief. Prolonged screaming inevitably leads to the gorging of the blood-vessels of the eye; and this will have led, at first consciously and at last habitually, to the contraction of the muscles round the eyes in order to protect them. At the same time the spasmodic pressure on the surface of the eye, and the distension of the vessels within the eye, without necessarily entailing any conscious sensation, will have affected, through reflex action, the lacrymal glands. Finally, through the three principles of nerve-force readily passing along accustomed channels—of association, which is so widely extended in its power—and of certain actions, being more under the control of the will than others—it has come to pass that suffering readily causes the secretion of tears, without being necessarily accompanied by any other action.
Although in accordance with this view we must look at weeping as an incidental result, as purposeless as the secretion of tears from a blow outside the eye, or as a sneeze from the retina being affected by a bright light, yet this does not present any difficulty in our understanding how the secretion of tears serves as a relief to suffering. And by as much as the weeping is more violent or hysterical, by so much will the relief be greater,—on the same principle that the writhing of the whole body, the grinding of the teeth, and the uttering of piercing shrieks, all give relief under an agony of pain.

He also cautions about seeing the use of a means of expression as static. What derived from one circumstance can be deliberately used in another, so that what may seem as a pattern relating to distress can be used for other intent; an example would be children deliberately using a trantrum to elicit a desired response, because they are learning to play on the reaction of their parents, rather than being genuinely distressed:

Every true or inherited movement of expression seems to have had some natural and independent origin. But when once acquired, such movements may be voluntarily and consciously employed as a means of communication.

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