Emotion and Thought: A Motor Theory of Their Relations [with Discussion by Knight Dunlap, James Melrose and Morton Prince.]
情绪与思维:两者之间的动机理论
Margaret Floy Washburn
Vassar College
In what sense, and for what reasons, do emotions paralyze thought; and when and why, if ever, do they aid it? These are the questions which in the short time at my disposal I am not, indeed, hoping to answer adequately, but on which I wish to offer a few reflections. The reflections will be made from the point of view of a motor psychology whose main assumptions I will ask you for the time to accept.
The first assumption is that while consciousness exists and is not a form of movement, it has as its indispensable basis certain motor processes, and that the only sense in which we can explain conscious processes is by studying the laws governing these under-lying motor phenomena. The second assumption is that the motor accompaniment of thinking, as distinguished from sensation, consists of slight, incipient or tentative muscular contractions, which if fully performed would be visible or audible reactions to a situation, but which as only tentatively performed are a kind of rehearsal of the reactions. They may also occur unconsciously. Both full and tentative movements may be organized into systems, which may be of movements either simultaneously performed, as when we play the piano with both hands, or successively performed, as when we repeat a phrase; they may also either be steady tonic muscular contractions, such as are involved in maintaining an attitude (these I have called static movement systems), or involve actual change of position (these I have called phasic movement systems). All association of ideas and thus all thinking involves on this hypothesis the organization of tentative movements into systems.
But the word thought may be used in two senses. It may mean reverie or undirected thinking, or it may mean thinking directed towards a problem or purpose. In the first case, each idea suggests the one that follows it, but here its influence ends and our thoughts wander: A suggests B and then is forgotten, while B suggests C without aid from A. In the other case, that of directed thinking,
( 105) a long series of ideas is governed by the idea of an end, problem, or purpose, and irrelevant wandering thoughts are inhibited. Now the third main assumption that I shall ask you to bear in mind is that the peculiarly persistent influence of the idea of an end or purpose as compared with that of ordinary ideas is due to its association with a persistent bodily attitude or static movement system which I have elsewhere called the activity attitude. I have said of this attitude that "in its intenser degrees it is revealed to introspection as the ‘feeling of effort.’[1] Introspection further indicates that it is not due to shifting innervations but to a steady and persistent set of innervations. It appears from introspection, also, to be in its intenser forms a bodily attitude involving a kind of tense quietness, a quietness due not to relaxation but to a system of static innervations." Through the inherent and characteristic persistence of the innervations involved in the activity attitude as members of a static movement system, the innervations connected with the problem situation may exert the long enduring influence which is characteristic of directed thinking. This theory holds that "the motor innervations underlying the consciousness of effort are not mere accompaniments of directed thought, but an essential part of the cause of directed thought"—a proposition that has recently received support from the results of experiments by A. G. Bills,[2] indicating the impossibility of thought during complete muscular relaxation.
The motor theory under consideration thus bases all thinking on the occurrence of tentative movements, and bases directed thinking on the occurrence of a persistent motor innervation here called the activity attitude. Whatever interferes with tentative movements will inhibit all thinking; whatever interferes with the activity attitude will inhibit directed thinking. The tentative movements underlying thinking are, it is reasonable to suppose, chiefly those of the smaller and more delicate muscles of the body, such as those of the eyes, the fingers, and above all the muscles involved in speech. For it is impossible that the large muscles, say of the arms and legs, should be capable of enough variety of movement to supply the multitude of differing movements needed to form the basis of ideas. In the activity attitude, on the other hand, it is largely the trunk muscles that are concerned, as may be introspectively observed in its intenser form, the feeling of effort.
While the assumptions about thought which have just been outlined may not command assent, we shall all agree in the follow-.
( 106) -ing statements about emotion. An emotion occurs in a situation of vital significance to the organism; primitively, perhaps, the flight, fighting, or mating situations. In such a situation, the possibilities of response may be divided into several classes. First, there may occur adaptive movements of the striped muscles, adequately meeting the situation: movements of flight, fighting, or mating. Secondly, there may be non-adaptive movements of the striped muscles. Some of these, like human facial expressions, are survivals of movements formerly adaptive, or adaptive under conditions somewhat but not wholly similar. But the most striking instance of non-adaptive movements is constituted by what may be called the motor explosion: the kicks and screams of the baffled child, the curses and furniture abuse of the baffled adult, the wild expansive movements of extreme joy. A motor explosion tends to happen when adaptive response is impossible. Thirdly, there may occur internal changes produced through the sympathetic and glandular systems.
On a motor theory, the question as to when and how emotion will interfere with thought becomes the question as to which of the various things we do in an emotional situation are likely to interfere with the things we do in thinking. Which will tend most to interrupt the tentative movements underlying ideas and the activity attitude underlying directed thinking: adaptive striped muscle reactions, non-adaptive striped muscle reactions, or visceral reactions produced through the sympathetic and endocrine systems?
Clearly, one motor process can interfere with another only when it is physically impossible for the two movements or attitudes to occur together, as for example it is impossible to raise and lower the arm at the same time. Nothing can interfere with a movement but another movement. The motor theory would go farther and say that when one nervous process inhibits another, it must be because the two are connected with incompatible movements. Further, what is true of single movements is true of their combinations: whenever two movement systems are simultaneously stimulated, if one contains a movement incompatible with some movement in the other, the systems cannot be simultaneously performed and will tend to inhibit each other, unless, indeed, they become smaller by dropping out the incompatible elements. The functioning of such smaller movement systems may be regarded as responsible for dissociation, and a tendency toward it as characteristic of those individuals whom we call hysterics.
We may turn, then, to the first type of response possible in an emotional situation, namely, adaptive movements of the
( 107) striped muscles. Will these be incompatible with thought? It is obvious that one motor process will be more likely to disturb others, the more muscles it involves, that is, the more wide-spread its distribution over the body. Now definitely adaptive movements of the striped muscles, as compared with the non-adaptive motor explosion, will as a rule involve only definitely demarcated groups of muscles, and these will be for the most part the larger muscles—those of the limbs. Thinking, on the other hand, is, according to the hypothesis here adopted, based chiefly on contractions of small muscles capable of a large repertory of different movements. Stratton[3] reports the case of an aviator who, during a tail-spin fall of four thousand feet, made all the movements needed to remedy the trouble with his plane and straighten it out, while experiencing a series of intensely vivid mental images from his past life, beginning with childhood. These images, on the theory here presented, would be based on tentative movements in certain muscles, which were evidently not incompatible with actual movements in the other muscles needed to meet the emergency. Stratton deduces from this and other similar cases that it is only the intenser degrees of emotion which interfere either with coordinated action or with thinking. It is true, however, that the more serious the situation which excites emotion, the more extensive the adaptive movements are likely to be. Thus one fighting situation may require only a short, well-directed attack, while another demands a desperate struggle calling into play all the body muscles, and, by virtue of the alert watching of the enemy's movements needed, many of the smaller ones. Except in extreme cases, however, adaptive movements, it would appear, need not interfere with thought.
What, now, is the relation of thinking to the second type of response in an emotional situation? The motor explosion or non-adaptive striped muscle response has been often overlooked by psychologists. For example, Wechsler[4] divides emotional reactions into choc" or visceral responses and "behavior reactions," which involve orientation to the stimulus, thus ignoring the motor explosion, which is neither visceral nor oriented. Yet it is really an important and interesting phenomenon. As we have noted, it occurs when adaptive response is impossible. This is usually because such responses are repressed either by external force or by internal inhibitions, as in impotent anger. The case
( 108) of the motor explosion resulting from joy, by the way, is a curious one. People do, of course, all sorts of wildly irrelevant things in extreme joy. Now here adaptive response is impossible not because it is being prevented, but because it is non-existent. There is nothing one can do in joy that has any essential appropriateness to the situation, in the way that knocking a man down has essential appropriateness to anger. Joy represents not a situation where something needs to be done, but the release of energy that has been occupied in long-continued tensions, which, since it has no pre-ordained channel, diffuses itself into many channels.
There is high probability that the motor explosion, in which any and all muscular systems, including those of speech, may take part, will interfere with thinking, if thinking has any motor basis at all. A man in a wildly gesticulating, vociferous fit of rage has no muscles left at liberty to think with. In its milder form, the motor explosion is identical with general restlessness, which also involves a wide range of muscles, although in less violent contractions. And it should be noted that a motor explosion may occur in the form of tentative rather than actual movements. In such a case, I would suggest, it forms the basis of the experience of mental panic. When no adaptive movement is possible, there may occur impulses towards all kinds of non-adaptive movements; these tentative movements in all directions may well produce the effect of making our brains whirl, as we say, and would evidently through their widespread character be antagonistic to clear thought.
Thirdly, will the visceral reactions, those dependent on the autonomic and glandular systems, interfere with thinking? Why should they, on a motor theory of thought? If thinking is based on movements and attitudes of the striped muscles, nothing can interfere with it but antagonistic movements and attitudes of these muscles. And the internal changes produced through the autonomic and endocrine systems do not involve striped muscles. May we not say, then, that visceral changes per se cannot disorganize thinking?
Visceral changes have, however, indirect effects upon the external muscles. Cannon has pointed out their important influence upon adaptive responses; the pouring of sugar into the blood, the neutralizing of fatigue poisons, the checking of digestive processes—all serve the purpose of producing more powerful reactions of an adaptive nature, for instance, movements of fighting or flight. Such movements, as we have just seen, are not necessarily incompatible with thought. What, now, is the relation of non-adaptive movements to visceral changes? Since non-adaptive
( 109) movements are in themselves useless, and since, as we have seen, they are likely to interfere with thought, have such movements any function, or shall we class them with nature's superfluous products? We seem to "feel better" after them! Pascal and Davesne[5] in a recent article suggest that the non-adaptive movements called "tics" are useful in preventing the emotion from invading the "vegetative" or visceral plane, that is, the autonomic and endocrine systems; the more the emotion discharges into motor paths the less it goes into visceral paths. Various writers imply that the organism seeks to avoid the visceral discharge; why should it be avoided? The normal function of discharge into the autonomic and glandular level is to aid the performance of adaptive movements. Should these be interfered with either the visceral discharge is worked off in motor explosion, or it remains in the organic level. And according to Cannon,[6] "if these results of emotion and pain are not `worked off' by action, it is conceivable that the excessive adrenin and sugar in the blood may have pathological effects." When, then, adaptive movements remain blocked, it is probably for the safety of the organism that the visceral processes should work themselves off in a non-adaptive motor explosion. And so they have indirectly, though not directly, a disturbing influence on thought.
When and how does emotion aid thought? There is time for only a few reflections on this topic.
It is a well-known fact that emotional states may function as the associative links between ideas, thus forming what in the Freudian terminology are called complexes. Thinking of this type, however, is highly inefficient, and emotion cannot be said to do thought any service in thus binding together what might better be left separate. Another type of thinking which may occur along with emotion is, as we have seen, dissociated thinking, made possible by the shrinkage of movement systems so that in-compatible movements are dropped out. MacCurdy,[7] in his Psychology of Emotion, regards such subconscious and co-conscious ideas as forming the very essence of affect, the conscious aspect of emotion. It is, naturally enough, from pathological cases that he draws the evidence for his statement that "the quality of the affect is determined by the sum total of unconscious complexes that are activated, and may therefore have an infinite variety."
( 110) But again, emotion cannot be said to aid thought in thus permitting itself to be accompanied by dissociated ideas.
Yet if thought has a motor basis, it must need some energy, and the visceral changes in emotion are supposed to supply an extra amount of energy; they should be able, therefore, actually to aid thought. According to the hypothesis here presented, efficient thinking requires two factors: a varied supply of tentative movements to serve as the basis of ideas, and a persistent, tense attitude of the trunk muscles associated with some of these ideas to secure their influence during a considerable period. Now when the amount of extra energy generated in the visceral discharge is not too great, it may pass over into the tentative movements underlying ideas, so that their number and speed are increased and new combinations of then occur without the long effort of directed thinking. Experience shows that the flow of ideas is heightened by mild emotion. Moreover, a part of the emotional energy may, even in discharging through non-adaptive movements, relax an inhibition that has been repressing the flow of ideas. But the most important function of emotion in aiding thought will relate to the activity attitude.
Directed thinking never occurs without a motive. Reverie, the drifting of ideas, may go on while we are indifferent, but if we suddenly begin purposeful thinking, it is because some affective process has been stirred up. And also, of course, because direct, external reaction to the stimulus that thus taps the storehouse of the organism's energy is blocked; if it were not blocked, there would be no need of thinking. Thus we have directed thinking as the outcome of the very type of situation that occasions emotion; but in directed thinking the energy thus set free and blocked finds its outlet in the tense quietness of the activity attitude instead of in the random and uncoordinated movements of the motor ex-plosion. The setting free of energy in the visceral levels, so far from being incompatible with thought, is necessary for directed thought.
Why does this energy sometimes discharge into restlessness and useless movements and sometimes into the attitude of tense quietness? At least three factors seem to be concerned in the decision of this point: the amount of energy released by the situation, and the thresholds of discharge of the non-adaptive pathways and of the activity attitude, respectively. If the situation is desperate and the amount of energy set free is great, the tensely quiet attitude and the tentative movements of thought, requiring so little energy, will be inadequate outlets. But evidently the seriousness of the situation is not the only factor; in less desperate situations
( 111) it will not always be the weaker desires that produce in a given individual directed, purposeful planning and the stronger ones mere restlessness. With a given. amount of energy stirred up by the situation, certain conditions evidently open the pathways to diffuse discharge and block those to the concentrated tonic discharge of the activity attitude. One of these conditions is certainly fatigue. In fatigue all muscles tend to relax, and the activity attitude, which involves steady and continued contraction of certain muscles, is more readily fatigued than is restlessness, which involves diffuse contractions followed by relaxations. Fatigue is involved also in another condition that determines whether we shall think or merely be restless, namely, the lack of ideas. No one can keep on trying to think on a subject of which he has no knowledge. In fruitful thinking, when out of a storehouse of information one relevant idea after another occurs to us, the activity attitude is refreshed by little relaxations along the way and fatigue is postponed.
On the motor theory here suggested, emotion, then, interferes with thought only when the movements made in emotion are in-compatible with the movements and attitudes essential to thinking. This will be most likely to happen when the energy set free by the glandular processes in emotion discharges into the diffuse and random movements of the motor explosion. Emotion will aid thought when conditions favor the discharge of this energy into the maintenance of a steady innervation of the trunk muscles, which is the basis of introspectively reported feelings of will, determination, activity, or effort, and which secures the steady influence of the idea of a goal.
DISCUSSION
Dr. DUNLAP (The Johns Hopkins University): Dr. Washburn's paper has given rise in me to some emotions which I hope will not interfere with my thinking. Before I take up the main point that I want to inflict on you in connection wit h this paper, I would like to say that I wish that Dr. Washburn's optimistic statement were true. I am afraid it is not. She said, "People cannot keep on trying to think about topics of which they have no knowledge." Would to God that, were true! I don't know what would happen to much of our psychology if it were true.
Some of these emotions were aroused by this fact, that I suppose I can say that Dr. Washburn and I are the pioneers in this movement on theoretical foundation of thought in motor processes. My own formulae were put forth before behaviorism had begun to behave, and I have deplored—I suspect Dr. Washburn also has deplored—the extremes to which the motor theory has been pushed in behaviorism. I feel that before the connection between thinking and emotion shall be worked out on the basis of the motor theory—the motor hypothesis of thinking—that hypothesis itself needs a great deal more elaboration and correction.
In the first form I assumed—I think Dr. Washburn still assumes, if I under-
( 112) stand her paper correctly, as she did it the start that all thinking requires muscular contraction. The more I attempt to connect that theory with the actual facts of life and with the learning process, as we know it now from our laboratory work, the more improbable does that become. It is a serious question at present whether that theory can be still held. Experimental work now in progress in several universities bearing upon the particular point as to whether implicit reactions—I do not know whether Dr. Washburn would accept that behavioristic term, but it expresses the older view—can be demonstrated as occurring in typical thought processes. These experiments must tell the tale, before we can go further.
Personally I have had to modify my theory and assume that the thought processes during the learning period, during the period of modification, are motor in full. Muscular contractions are involved. I believe we can demonstrate many of the things Dr. Washburn has pointed out in connection with disturbances of the thought process in the incipient or learning stages. I have a suspicion that. after thought has become crystallized, as it were, a great deal of our thought is routine thinking, even when it is highly efficient, that that stage has passed away, and that the muscular contractions are no longer needed.
That is an experimental matter, a matter that will be experimentally deter-mined I am tolerably sure within the next five years, which is of vital importance in this matter which Dr. Washburn has brought up.
There are one or two other things, if I may take a little of your time, which I would like to speak about. One is a minor matter with regard to the illustration which Dr. Washburn used, taken from Dr. Stratton's story of the aviator. I am beginning more and more to distrust all that type of evidence. It is a very good illustration of a very interesting type of evidence. From the point of view of dreams, I no longer believe people dream what they afterwards record. There is very strong evidence in dreams as recalled and in cases of this kind as recalled of illusions of memory occurring. Conditions are exceedingly favorable for a man afterwards speaking as if be (lid think so and so during that period, when he did not think it. All that is a very interesting type of evidence which requires scrutiny. It does not at all invalidate Dr. Washburn's illustration.