The Varieties Of Stammer are many. They all arise from-1. Diffi culty to produce voice ; 2. Difficulty to produce voice in quantities adjusted to the syllable's demands; 3. Difficulty to produce the elementary sounds; 4. Difficulty in joining such sounds together ; and in each of these dames there are varieties.
Variety I arises from ill-regulated respiration, in which the effort to vocalise is accompanied with a feeling of insufficiency of breath. The stammer proceeds from an attempt to- speak on an involuntary inspb ration. A holding breath cannot be maintained on an involuntary inspiration, and therefore voluntary respiration for speech must always begin with an inspiration of breath. The physiology of this stammer indicates a discipline for its removal. The organs of respiration must be drilled to rightly change the involuntary act of respiration to the voluntary, which, with a course of rhythmue, will effect a permanent cure.
2. Tho difficulty in producing voice which is occasioned by an involun fary closure of the glottis. In this variety of stammer, instead of the Larynx receiving the adjustment for vocalisation in ready obedience to the will, the glottis suddenly closes, either by an involuntary associate movement, or by a tetaide spasm, probably in most cases by the latter.
Dr. Arnott pointed out the nature and means to cure it. His remedy consists in keeping open the glottis, by issuing a drone sound, such is the e of the word berry, before beginning to speak, and in join. ing this prefixed drone to the words. See his 'Elements of Physics,' vol. i.
3. The difficulty in producing voice which is occasioned by an invo luntary twitching of the glottis similar to chorea. This spasm is sometimes so excited as to preclude vocalisation, when only short iterations of breath are audible. The glottis must be disciplined on sounds of the crescendo form of loudness in a low pitch, and proceed gradually from the song-voice to that of speech. Itespiration and speech-voice training will follow, accompanied with general rhythmic discipline to the whole speech-apparatus for reading and speaking both verse and prose.
4. In this variety the difficulty is not to produce voice, but to control its quantities. Vocalisation freely takes place, but the event of two or three short or accented syllables following near together throws the glottal muscles into choreal spasm. The principles of discipline for the spasm will be similar to the preceding variety of stammer ; while a distinct discipline must be projected to acquire a higher degree of associating power.
5, The difficulty of uttering a vowel of uniform sound is a voice stammer, it being an absence of voluntary control over the vocalisation of the breath. The difficulty of uttering a diphthongal vowel may be either a voice or a speech stammer, and is often a combination of both. When the difficulty is to produce voice to begin the vowel, the stam mer is vocal; and when the difficulty is to change the adjustment from that for the initial, to that for the final sound of the diphthong, it is a speech stammer. When the difficulty is to produce voice to
begin the consonant, the stammer is vocal ; and when the difficulty is to change the adjustment from that for the initial to that for the final sound of the consonant, it is a speech stammer. Stammer on the single elementary sounds of speech can be permanently remedied only by a systematic training of the disobedient organ which occasions it. The organ must be disciplined to perform the necessary movements under all conditions of voice, which, accompanied with a general training of the whole apparatus of speech, conducted on rhythmical principles, will effectually remove the stammer.
6. Stammer occurs in all three modes of articulation, namely :— A consonant followed by a vowel, as bee; a vowel followed by a con sonant, as ebb; a consonant followed by another consonant, as bl of the word bled.
The difficulty in articulating the elementary sounds of speech to form syllables, can be permanently remedied only by a systematic training of the disobedient organs to perform their required move ments for the several adjustments of the mouth which are necessary to articulation. The training must be general and special The general is a rhythmic training of the whole speech-apparatus; and the special is a traiuiug of the disobedient organ to perform its various movements in articulation.
Our analytic description of stammering reveals three functional causes of inability to control the muscular movements which are re quired for utterance, namely : 1. Spasm, both of the tetanus and chorea forms. All muscles are liable to spasm. Spasm of the larynx, the tongue, the lips, and the inasseter muscle, are each sources of stammering.
II. Defect in the associating power, which combines the voluntary movements of different organs in one simultaneous act, or in an allied succession of acts. Defective association of vocalisation with respira tion will occasion stammer ; for perfect association of the voluntary movements of the larynx with those of the chest are required in utter ance. The movements of the larynx and chest are effected by means of the laryngeal, the recurrent, and the expiratory nerves.
III. Involuntary associate movements ; as after mimicking a stam merer it has been found that those muscular movements, which in the mimicry were voluntarily associated with 'the proper movements of utterance, have suddenly become linked to them so firmly in allied motion, that the mimicker is unable to dissociate them, and an actual stammer results.
The adoption of appropriate remedies for stammering then will depend on the following conditions, namely :-1. On the part of the speech-apparatus which is affected ; 2. On the cause producing the stammer ; and 3. On the vocal and other conditions undec.which the utterance is least affected, The appropriate remedies for each arc treated of in several works on the subject, among which we may men tion Thelwall's Letter to Clive on Stammering ; Cull's ' Observations on Impediments of Cull's Stammering Considered ;' and J. Hunt's' Treatise on the dure of Stammering.'