In childhood, the subthyroid or thyroid deficient, the cretinoid type, the type resembling the cretin, is fairly common. The peasant's face, with the broad nose and the tough skin, coarse straight hair, the undergrowth, physical and mental, a persistent babyishness and a retardation of self-control development, make up the picture. He needs an excess of sleep, sleeps heavily, needs sleep during the day, when awakened in the morning still feels tired, and rather dull and restless, dresses slowly, has to be coaxed or forced to dress, gets to school late nearly every morning, does badly at the school, reaction time, learning time and remembering time being prolonged as compared with the average, and is lazy at home lessons. He perspires little, even after exertion, yet fatigues easily, is subject to frequent colds, adenoids, tonsillitis, and acquires every disease of childhood that happens along.
Adolescence, the coming of menstruation, the first blooming of youth is delayed in the subthyroid. The secondary sex traits as they develop tend to be incomplete and to mimic those of the opposite sex. Yet in adolescence too there may be a sudden change and reversal of the whole process, a jump from the subthyroid to the hyperthyroid state. So a girl who has been dull and lackadaisical, with no complexion and every prospect of evolution into a wall flower, may be transformed into a bright-eyed woman, generally nervous and restless, high colored, and possessed of a craving for continual activity and excitement. Skin, hair and teeth become of the thyroid dominant type. The heart palpitates under the slightest stimulus, she perspires almost annoyingly, heat and emotion are prostrating. If such a transfiguration does not occur, the effect of the reconstructions of puberty is to create a person with about the following characteristics.
1. Height below the average 2. Tendency to obesity (toward middle age) 3. Complexion sallow 4. Hair dry—hair line high 5. Eyebrows scanty, either as a whole or in outer half 6. Eyeballs deep-set, lack lustre, in narrowed slits 7. Teeth irregular, become carious early 8. Extremities cold and bluish 9. Circulation poor. Subject to chilblains
Intellectually, these people vary enormously, depending upon which of the other glands will enlarge to compensate for the deficiency of the thyroid. If the growth of the skull has left a roomy sella turcica for the pituitary to grow in, the intellect may be normal or even superior, though energy is below par. If this is not possible and the adrenals have to predominate, a lower, more animal and less self-controlled type of mentality is produced.
In direct contrast to the subthyroid types is he who originally was hyperthyroid. During childhood he is quite healthy, thin, but striking robust, active, energetic, generally fair-complexioned with nose straight and high bridged, eyes rather "poppy," teeth excellent, regular, firm, white with a pearly translucent enamel. These children are always on the go, never get tired, require little sleep. Seldom will one of the classical children's diseases strike them, measles perhaps, but no other. Adolescence for them, however, is more apt to be stormy and episodic, adjustment to the new world of people and things is much more difficult, wanderlust is acute. All an expression of cells keyed up, charged with energy that must flow somewhere or explode.
The ruddy live-wire, recognized everywhere as bubbling with vitality, the life of any group, the magnetic personality may, however, be shocked by some seismic event like the death of a father or mother, or the ruin of some cherished ambition. A break in the balance of the other glands follows quickly and disablement and invalidism, which may cure itself after some years, remain stationary, or descend to the worst forms of thyroid deficiency.
During maturity, the type are characterized usually by a lean body, or tendency rapidly to become thin under stress. They have clean cut features and thick hair, often wavy or curly, thick long eyebrows, large, frank, brilliant, keen eyes, regular and well developed teeth and mouth. Sexually they are well differentiated and susceptible. Noticeable emotivity, a rapidity of perception and volition, impulsiveness, and a tendency to explosive crises of expression are the distinctive psychic traits. A restless, inexhaustible energy makes them perpetual doers and workers, who get up early in the morning, flit about all day, retire late, and frequently suffer from insomnia, planning in bed what they are to do next day.
Certain types of thyroid excess associated with the thymus dominant next to be described are peculiarly susceptible to emotional instability. They are subject to brain storms, outbreaks of furious rage, sometimes associated with a state of semi-consciousness. To emphasize the analogy to epilepsy, their attacks have been called psycholepsy. Among the Italians especially they were watched and reported during the War, when the explosive fits were seen to take the form of irresponsible acts of insubordination or violence.
THE THYMO-CENTRIC PERSONALITIES
During the first period of childhood, up to five, six or seven, or more accurately, up to the point at which the permanent teeth begin to appear, every child may be said to be a thymus-dominated organism, because the thymus, holding the other endocrines in check, controls its life. That is why up to the third and fourth years at any rate, most children seem alike. Closer observation, however, reveals points of differentiation and signs of the coming potencies of the other hormones. During the second period, up to puberty, these marks of the deeper underlying forces of the personality make themselves more and more felt. The thymus, like a brake that is becoming worn out, continues to function in a progressively weaker fashion. Until with the arrival of the gonadal (ovaries' or testes') internal secretion, its influence is wiped out.