Because of their symptomatical significance for the emotions, all these movements are called expressive movements. As a rule they are entirely involuntary, either reflexes following emotional excitations, or impulsive acts prompted by the affective components of the emotion. They may be modified, however, in the most various ways through voluntary intensification or inhibition of the movements or even through intentional production of the same, so that the whole series, of external reactions which we shall have to discuss under volitional acts, may take part in these expressive movements (§ 14). These different forms of movement may be entirely alike in external character and may pass into each other without sharp limitations on their psychical side, so that for the outside observer they are as a rule indistinguishable.
5. According to their symptomatical character, expressive movements may be divided into three classes. 1) Purely intensive symptoms; these are always expressive movements for more intense emotions, and consist of stronger movements for emotions of middle intensity, and of sudden inhibition and paralysis of movement for violent emotions. 2) Qualitative expression of feelings; these are mimetic movements, the most important of which are the reactions of the oral muscles, resembling the reflexes following sweet, sour, and bitter impressions of taste; the reaction for sweet corresponds to pleasurable emotions, those for sour and bitter to unpleasurable, while the other modifications of feeling, such as excitement and depression, strain and relief, are expressed by a tension of the muscles. 3) Expression of ideas; these are generally pantomimetic movements that either point to the [p. 173] object of the emotion (indicative gestures) or else describe the objects as well as the processes connected with them by the form of the movement (depicting gestures). Obviously these three classes of expressive movements correspond exactly to the psychical elements of emotions and their fundamental attributes: the first to their intensity, the second to the quality of the feelings, and the third to their ideational content.
A concrete expressive movement may unite all three forms in itself. The third class, that of expressions of ideas, is of special psychological significance because of its genetic relations to speech (cf. §
21, 3).
6. The changes in pulse and respiration that accompany emotions are of three kinds. 1) They may consist of the immediate effects of the feelings that make up the emotions, as, for example, a lengthening of the pulse-curve and respiration-curve when the feelings are pleasurable, and a shortening of the same for unpleasurable feelings (cf. sup. p. 87).
This holds only for relatively quiet emotions where the single feelings have sufficient time to develop. When this is not the case, other phenomena appear which depend not merely on the quality of the feelings, but also, and that mainly, on the intensity of the innervations due to their summation.
2) Such summations may consist of intensified innervation, which arises from an increase in the excitation resulting from a summation when the succession of feelings is not too rapid. This increase shows itself in retarded and strengthened pulse-beats, since the intense excitation effects most the inhibitory nerves of the heart. Besides these there is usually an increased innervation of the mimetic and pantometic muscles.
These are called sthenic emotions. 3) If the feelings are very violent or last an unusually long time in a single direction, the emotion brings about a more or less extended paralysis of the innervation of the heart and [p. 174] of the tension of the outer muscles. Under certain circumstances disturbances in the innervation of special groups of muscles appear, especially those of the diaphragm and the sympathetic facial muscles. The first symptom of the paralysis of the regulative cardiac nerves is a marked acceleration of the pulse and a corresponding acceleration of the respiration, accompanied by a weakening of the same, and a relaxation of the tension of the external muscles to a degree equal to that in paralysis. These are the asthenic emotions. There is still another distinction, which is not important enough, however, to lead to the formation of an independent class of physical effects of emotions, since we have to do here only with modifications of the phenomena characteristic of sthenic and asthenic emotions. It is the distinction between rapid and sluggish emotions, based upon the greater or less rapidity with which the increase or inhibition of the innervation [ sic ] appears.