STAMMERING, a defect of speech due to failure in co-ordinate action of certain muscles and their appropriate nerves. It is analogous to some kinds of lameness, to cramp or spasm, or partial paralysis of the arms, wrists, hands and fingers, such as is sometimes attendant upon certain exercises; for speech is a muscular act involving the co-ordinate action of many nerves and muscles.
The words stammering and stuttering prac tically denote the same infirmity, although stut tering is now limited more or less to the futile repetition of sounds, While stammering covers the whole defect hesitation, glide, stop, hold ing on to the sound, as well as repeating it. Because stammering is proved to be pretty wide spread in Prussia, Great Britain and its colonies, and the United States, and uncommon in Italy and Spain, the question suggests itself whether languages of Teutonic origin are not more apt to generate it than languages of Latin origin. This chief of the imperfections of speech may be hereditary, and it may be acquired by imita tion. Like yawning, it is infectious. It may be the abiding result of mental strain or shock. Fever may bnng it on, epilepsy, hysteria, or any serious nervous affection or strong emotion, temporary failure of health, any excitement, or even soreness of the mouth. It rarely shows itself earlier than at four or five years of age. It usually begins in youth, but may be produced at any later age. A much larger proportion of males than of females stammer. Stammering used to be ascribed exclusively to the organ of articulation, the mouth; to faulty setting of the teeth or the jaws, to the largeness and thick ness of the tongue, its weakness of movement, its excessive vigor, etc. At present in the re search for the cause and cure of stammering full account is taken of the vocal cords or cushions and the vocal chink.
Stammering occurs in the mouth, the organ of articulation. Its proximate cause is always in the larynx, the organ of voice. Sometimes the lungs, the organ of breathing, complicate the uncertainty and unsteadiness of the vocal cords and the vocal chink in the larynx. A current of air, variously shaped by the mouth as a whole, is what is called a vowel. A stam mer on a vowel can only take place in the vocal chink, rima glottidis. The sounds called conso nants are produced by closures, more or less firm, of contents of the mouth. Thus, b, 0, an, w, by the closure of the two lips; f, v, of the lower lip and upper teeth; g soft and sh, of the teeth; / and th, tongue and upper teeth; t, d, as, s, z, y, tip of the tongue and fore gum; g hard and k hack edges of the tongue and back gum.
Stammering may occur at any of these six closures. It is, perhaps, most apt to occur at the labials b, p, the dentals d, t, the gutturals g hard, k, because for these the closure is firm est. The stammerer has no difficulty in setting lips, teeth, tongue and gums against each other as required. His difficulty is to relieve the clos ure, to get at the vowel which is to follow the consonant. The tongue, for example, will not part with the teeth seems to cling spasmodically to them because the current of air, the vowel, does not come at the proper instant through the vocal chink to relieve it. In this way the three observable modes of stammering are explained. If the vocal chink does not open soon enough there is a stop stammer; if it flutters, there is a stutter; if it opens too soon, there is a glide stammer. But, further, the lungs expand and contract by nervous and muscular energy; and, besides, the muscular and nervous machinery of the breastbone, ribs, midriff and upper abdo men are all concerned in that expansion and contraction. These complicated and delicate bel lows which supply air under pressure to the organ of voice may be defective, out of order, misused. Their working is to be closely ob served in the case of each stammer. Stammer ers, as a rule, breathe badly. They constantly try to speak when their lungs are empty.
Stammering can be cured. It often disap pears gradually without special effort at cure, through an improvement in the general health and especially of the nervous system. Improve ment generally takes place as age advances. In some cases resolute endeavor is demanded. A %laving motion of the arms, time kept to a baton were favored as cures at one time. They were on the lines of the musical methods of cure intoning, chanting, singing which were based on the fact that most stammerers can sing without difficulty. The stammerer should be taught to regulate the breath, and he should work for a habitual use of the chest voice for deeper, steadier vibration of the vocal chords since stammering usually occurs with use of a head voice. The stammerer should take exercise in a chest voice, on the sounds (seldom vowels) at which a stumble is apt to be made.