|494||THE POPULAR SCIENCE MONTHLY.|
cate manipulation is here what counteracts the convulsive action of the diaphragm.
Gaping is also a convulsive form of inspiration, which, however, is not so short and violent as the hiccough. In gaping, moreover, those muscles which raise the walls of the chest are at once brought into prominent action; while, further, a rapid contraction of the diaphragm is necessary before the climax can be reached, after which a somewhat rapid fall of the thorax produces a quick expiration. The important part which is played by the rise of the chest is particularly shown by the fact that in very violent gaping the head is thrown backward, and the shoulders raised, in addition to which even the arms are sometimes stretched upward. During the gaping inspiratory process the mouth is opened spasmodically, and at the same time the soft palate is spasmodically raised, closing the air-passage of the nose. The whole phenomenon, including the sense of satisfaction after the inspiration, seems an indication of a strong desire for air, and the existence of this desire under those circumstances in which gaping is generally observed—sleepiness, for instance, or weariness—is readily explainable. Such circumstances are accompanied by a general inactivity of the nervous system, from which results a weak respiratory action, insufficient for the body when awake.
Stammering results from efforts to talk while a similar action to that which produces hiccough is going on. The difference is that, in stammering, the contractile spasm of the diaphragm is longer. During its continuance no expiration can take place, and, as speech depends upon the existence of an issuing stream of air, it is impossible for a person while suffering such a spasm to produce any sound. Ineffectual and therefore exaggerated efforts to create sound with the organs of the mouth and throat give rise to distressed grimaces, and this dis- tressed expression must necessarily be augmented by the fact that, by so long delaying expiration, a want of breath is felt and the circulation of the blood interrupted. "When at length the spasm ceases, and is followed by a quick expiration, the natural condition is restored till again destroyed by a fresh spasm. But there may be no attempt to speak, and yet the cause of the phenomenon (the spasm in the diaphragm) may be experienced; in this case it will not cause stammering, and may be quite imperceptible to the observer. If, now, as appears from the above, stammering is only an occasionally observed symptom of a contractile spasm in the diaphragm, it must be clear that all attempts to cure stammering by exercising the organs of the mouth and throat must be unsuccessful, and that this defect can be efficiently treated only by following rules already given for the treatment of hiccough. A quiet, unhurried inspiration must be followed by an expiration as slow and long as possible, the issuing stream either being employed in speech or not. With this treatment the motor nerves of the diaphragm can most effectually recover from their