Under normal conditions, entirely aside from nervousness, the voice instinctively reflects every phase of sentiment and emotion. Love and hate, sorrow and joy, anger, fear, and rage, each is clearly expressed by the quality of the tones, independent of the meaning of the spoken words. All these fine shades of tone quality result from muscular adjustments of the vocal mechanism. In some mysterious manner the outflow of motor impulses to the throat muscles is governed by the nervous and emotional states.
This form of muscular contraction is in one sense not involuntary. As the voice is voluntarily used, all the muscular contractions involved are voluntary. Yet the minute contractions producing tone qualities expressive of emotion are distinctly involuntary. More than this, these contractions cannot usually be inhibited. An angry man cannot make his voice sound other than angry. Our voices often betray our feelings in spite of the most earnest efforts at concealment.
While the voice always normally and involuntarily adopts the tone quality indicative of the emotional state, this action of the vocal organs may be voluntarily and purposely performed. A perfect command of these fine shades of tone quality renders the voice a very potent instrument of expression. For the purposes of dramatic singing this form of vocal expression might be of great value. It is to be regretted that dramatic singers of this day pay so little attention to purely tonal expressiveness. This is probably due in great measure to the prevalence of throat stiffness, which robs the voice of much of its expressive power.
(c) Contractions of the Throat Muscles, caused by Attention to the Throat
When a physician attempts to examine a child's throat, the tendency of the throat muscles to this form of involuntary contractions is apt to be evidenced. The jaw stiffens and the tongue rises; for a time the rebellious little throat refuses to remain quiet and relaxed.
People usually have some such difficulty the first time they submit to examination with the laryngoscope. This is very apt to occur, even in the case of experienced singers. Needless to say, this form of muscular contraction is entirely involuntary; it even defies the most earnest attempts at prevention. Comparatively little experience is required for normal people to overcome this tendency. The throat usually becomes tractable after one or two trials with the laryngoscope.
Vocalists are well aware of the proneness of one part of the vocal mechanism, the tongue, to stiffen in consequence of direct attention being paid to this member. In this connection Frangçon-Davies remarks: "When the writer in early student days concentrated his attention upon his tongue he found that this member became very stiff and unruly indeed." (The Singing of the Future, London, 1906.) Leo Kofler speaks of the same tendency: "Tell a pupil to let his tongue lie flat in his mouth; he draws it back till it dams up his throat." (Werner's Magazine, Oct., 1899.)
(d) Throat Stiffness due to the Radiation of Nerve Impulse
Two types of muscular tension due to the radiation of motor impulses were noted; first, the stiffness incident to the early stages of practice in complex activities; second, the stiffness caused by the attempt to perform complex activities in a mechanical manner by paying attention to the individual component movements and contractions. To both these types of muscular stiffness the voice is especially subject.
It is not easy to find a perfect illustration of throat stiffness incident to the early stages of instruction in singing. For this the chief reason is that the later form of stiffness, due to the attempt directly to manage the vocal organs, is much more pronounced than the temporary early tension. As good an example as possible would be the following: Let some one possessed of a fine natural untrained voice sing a steady tone and then attempt to trill on the same note. The attempted trill will invariably indicate a much higher degree of stiffness than the single tone.