Yet, should the administration of the thyroid cease, an almost immediate reversion to the original vegetative condition is inevitable. After a few days, reactiveness slows down, the child will speak only when spoken to, will sit quietly in a chair all day and act semi-anesthetized. Gradually hair and skin return to the previous cold-blooded animal state, and the whole picture of the cretin is in full bloom. Supplying the internal secretion of the gland promptly repeats the transformation.
One wonders what is to be the ultimate fate of these reformed cretins. Since the tale of the opening of life to them, once considered hopeless idiots, is scarce a generation old, we have no data, as yet, as to the character of their children or grandchildren, their adventures and vicissitudes, in short, their life history. Those of whom we have any record are normal and healthy school children or workers, alive to the interests of childhood or their occupation and social circles. No one outside their family knows that they are cretins, and the most acute observer would be hard put to it to suspect. What a theme for the reflections upon appearances the eminent Victorians loved!
There are possibilities the imagination may envisage. One may suppose such a cretin, with all his other ductless glands intact, grown successfully to manhood under careful medical guidance. No one but himself is aware of his affliction, outside of his medical advisers. Luck aids him to rise in the world, or perhaps he has been born with a spoon of the precious metals in his mouth. Adolescence, love and marriage dance their sequence. Our hero of course keeps his dread secret to himself. Whether such an omission of confidence would entitle his wife to a divorce is something courts will be called upon to decide sooner or later. But, without anticipating, the honeymoon involves a trip to the South Seas. A storm and a wreck throws them alone on an island, tropical, easy to live on, and rescue in the course of a few months certain. The man, to his horror, discovers that he has saved of his medicaments only a pill box containing half a dozen of thyroid tablets, his requirement being one a day. He sees them go day by day. Finally they are all gone. He feels his faculties slipping hour by hour. Shall he tell her? Indecision grips him, and he delays until the day when his consciousness sinks to the point where his mind no longer grasps his problem. The wife must endure the spectacle of the enchantment of her husband, and his change from gallant lover to dull animal ogre. A new version of Beauty and the Beast!
Cretinism as one manifestation of a soul without thyroid or without enough thyroid is not all. The first great successes with thyroid were achieved in adults, particularly adult women, exhibiting a peculiar obesity, coldness, loss of hair and teeth and a remarkable lassitude and torpor that might be summed up as a chronic drowsiness, like a saturation of the blood with some narcotic drug. Or there may be a melancholia, or a lack of ability to seize the finer points of a mental process, or an argument treated in the abstract. Children are said to be lazy, slow or dull. They experience an irritating difficulty in understanding questions and expressing their wants and desires, and so are declared to be vicious, or stupid.
All these are grades of the degeneration which Ord, the Englishman, named myxedema. At its worst it is a sort of bloating and drying of the body and the mind. Then there is infantilism, which is helped by the giving of thyroid extract. It differs from the ordinary cretinism in that, while one is reminded of the latter by the physical stunting and the other stigmata, there is a certain amount of intelligence which enables the individual to hold his own while he is a child. He becomes a grown-up baby: at twenty prefers the company of children of ten, and passes under the evil influence of designing so-called normal persons. So dominated he will lie, steal, start fires, commit almost any crime, with no inherent flair for criminality, but because of a lack of independent judgment and inability to resist suggestion, and a desire to please friends. He is simply an overgrown child who still loves to play with toys, laughs and cries, becomes angry or afraid, unreasonably and ridiculously, and yells for mamma when thwarted or scared.
So much for what happens when there is not sufficient of the thyroid secretion in the blood and tissues. Now to consider the effects of an excess of it, the condition called hyperthyroidism, as the insufficiency of it is labelled subthyroidism. Too much thyroxin can be introduced into the system of a normal individual, or even a cretin by the simple administration of too large doses or over too long a time. Also a train of symptoms similar to those evoked by an oversecretion of the thyroid may be mobilized by the taking of too much iodine. Great sorrow, great joy, a sudden severe jolt to the nervous equilibrium, sexual excitement, an overwhelming anger or grief may leave in their wake a permanent hyperthyroidism. The symptoms are the reverse of cretinism and myxedema. There is an over-excitability of the nerves in place of sluggishness, and an over-reactivity of the whole organism to its environment. The heart's action is too fast, and under the slightest stimulus gets faster to the point of obtruding itself into the conscious mind as a palpitation. Instead of the lowered temperature and coldness of the cretin, there is a heightened temperature, one or two degrees above the normal, and a feeling of heat. The individual has a high warm color, does not sleep well, becomes or remains thin no matter how much he or she eats, is abnormally susceptible sexually, may suffer from a definite insomnia, is emotional, and perspires freely. Alert, neurotic or high-strung, magnetic, and imaginative are some of the descriptive adjectives applicable. The eyes are bright and prominent, large and beautiful, when they have not reached the stage entitled "pop-eyed." Or they may even become so protuberant and bulging as to develop the expression of one staring aghast at some ineffable horror. The latter is the feature of only the severest types, when there is an associated goitre, the combination designated as exopthalmic goitre.
There are, too, individuals in whom hyperthyroidism and hypothyroidism are mixed, or rather alternate. At one time they present the phenomena of the one, at another of the other. They are the people who complain of the cyclic quality of their moods and purposes. Their mood will be a heaven of exaltation and exhilaration, and then descend into a slough of despond from which they feel themselves inextricable. They are always talking about the ups and downs of their mental states. Headache and languor and fatigability, dry skin and lack of appetite for food or exertion on one day or for one week, give way on the next day, or for the next week, to an energetic gayety, and sweaty, flushed skin, a prominent appetite for food and every sort of activity. Driven to be forever on the go, for one period, in the next they feel like lying down most of the day, with no inclination for any life whatever. The stage of depression may go as far as a melancholia, the stage of stimulation as far as mania. They may simulate manic-depressive or cyclic insanity. Something restrains them, and holds them bound as in a vise in the one cycle. And then they are driven on beyond themselves by some invisible whip in the next.
THYROID AS DIFFERENTIATOR
Besides the action of the thyroid as energizer, lubricator, and growth catalyzer, it has a remarkable power as a differentiator of tissues. It determines the embryonic etchings of the different organs which in their totality comprise the unique individual. Every multicellular animal must first have existed as a single cell, the impregnated ovum. With the body and personality of the ovum, the creature is one and continuous, literally something the single cell has made of itself by sub-dividing and differentiating. In the process, the cell mass often goes through stages which stand out as individualities in themselves, that appear on the surface absolutely unrelated. So the caterpillar and the butterfly, to the naïve child, seem as far apart as worm and bird. In the case of the frog, the tadpole as a first sketch seems completely an impossible and wild absurdity. Yet we know that there is an orderly progression of events, a propagation of cells, a forward going arrangement of chemical reactions, that results in expansion and intricate complication of the organism. Just what the forces at work in this most mysterious of all natural processes are, has been an intellectual mystery that the best minds of the race have attempted to get rid of with words like pangenesis (Darwin). Words of Black (Mediterranean or Greek and Latin) origin, as Allen Upward has named them, always cover a multitude of ignorances. The glands of internal secretion, here, as in so many other dark places, provide the open sesame to certain long closed doors of biology. They offer themselves to us as the first definitely tangible agents which are known to keep the process of growth going, and undoubtedly initiate the marvelous unfolding of tissues and functions, organs and faculties summed up as development or differentiation.
Thus by the direct feeding of thyroid at particular points in the differentiating history most curious effects have been elicited. If the gland is made part of the nutriment, the bathing environment, of the tadpole, a hastening of its metamorphosis is attained. The tadpole lives not out its day as a tadpole, but precociously turns into a frog. But such a frog! It is a miniature frog, a dwarf frog, a frog seen by looking through the wrong end of the telescope, a frog not magnified, but micrified. Frogs have been so created the size of flies. There has occurred a splitting of the two reactions which ordinarily go hand in hand: the reaction of growth which is just brute increase of total mass or weight and volume, and the reaction of differentiation which is the finer process. The picture is a frog, but a frog the size of a tadpole, a frog which has missed its childhood, adolescence and youth, skipping over these transition stages into the adult age, as a pigmy.