Instinct and the Unconscious. W.H.R.Rivers
of discrimination and localisation which reminds us at once of the characters of protopathic sensibility. The special feature of interest from our present point of view is that this diffused and generalised reflex is wholly suppressed in the normal human being, the suppression having taken place in favour of reflexes delicately regulated according to the locality and, to some extent, according to the nature of the stimulus. Here, as in the case of protopathic sensibility, the suppression has been so complete that the presence of the mass-reflex is only revealed by disease or injury. It has been so successful that it needed the vast scale on which injuries of the central nervous system have been produced during the war to enable Head and Riddoch to discover the presence in Man of these old and long-suppressed processes.
In this case, and in the case of protopathic sensibility, we are not dealing with the suppression of individual experience, but with the suppression in the race of experience belonging to the earlier phases of its history. Through a special experimental procedure, or through the accidents of war, it has been possible to follow the suppression of this experience in the individual. The fact that this is possible suggests that the racial suppression is repeated in every individual as part of the recapitulation of the racial history. If this be so, however, the suppression takes place at so early an age that its detection is impossible. It would never have been suspected if the experiment and the [p. 30] clinical observations of Head had not pointed to the way thereto.
The special importance of suppression on the reflex and sensori-motor levels is that it reveals clearly the biological significance of the process. The exact localisation of fully developed cutaneous sensibility would be impossible if the early radiation and distant reference of the protopathic stage persisted. These features would furnish elements of vagueness and confusion wholly incompatible with the exact power of localisation which developed later and enabled the animal to modify its behaviour according to the nature of the external object by which the sensations were being produced. It is essential that reactions founded on the exact discrimination and localisation rendered possible by the epicritic system shall be prompt and definite. This would not be possible if the properties of the new order of sensibility were continually being complicated by sensations characterised by the old vagueness and the old inexactness of spatial reference.
Similarly, the uncomfortable feeling-tone of protopathic sensibility and the strongly affective aspect of the reactions of the thalamus need suppression when it is necessary to discriminate with exactness and to adjust behaviour to the more complicated conditions of life, made possible by the development of epicritic and cortical activity. In these cases, however, the suppression is less complete and only occurs when the affective accompaniments would interfere with the perfect adjustment of behaviour to the needs of the situation which the animal has to meet. The affective reactions lie ready to spring into activity whenever the situation calls for an emotional rather than an intellectual response.
In the case of the reflexes the need for suppression is imperative. The essence of reflex action is its immediacy and perfection based on the thorough organisation of the physiological mechanisms. The perfection of one of the higher reflexes would be hopelessly prejudiced if there were even a trace of the activity of the older mass-reflex with its diffuse character and implication of visceral processes. The movements of the [p. 31] localised reflex could not perform their task properly if at the same time they were involved in mass-movements of a wholly different kind. Suppression is here even more essential than in the case of conscious activity.
The argument of this chapter has been directed to show that the process of suppression by which elements of conscious experience pass into the "unconscious" is of the same order as the suppression which takes place on the sensori-motor and reflex levels. A number of processes have been found which form intermediate links connecting the suppression of highly complicated mental process at one end of the series with the suppression necessary for the perfection of reflex action at the other end of the series. In all cases we have to do with the means by which behaviour, whether of human being or animal, is adjusted to the needs with which man or animal is confronted. The suppression of conscious experience is only one example of a process which applies throughout the whole of the animal kingdom and is essential to the proper regulation of every form of human or animal activity. This suppression is only an example of processes even more fundamental in the animal economy. Every living process of the animal involves, not only activity devoted to the special end the animal has to meet, but also the inhibition of tendencies to activity of other kinds. The suppression which I have been considering in the last two chapters is only one aspect of the universal physiological property of inhibition. It is now recognised that the activity of every functional unit of the nervous system is of two kinds. Every unit forms part of a hierarchy in which it controls lower, and is itself controlled by higher, elements of the hierarchy. Control or inhibition belongs to the essence of nervous activity, and the lesson suggested by the study of sensation and reflex action is that the suppression by which experience becomes unconscious is only a special variety of the process of inhibition, common to every phase of animal activity.
There is one aspect of the psychological processes I have been considering which I should like especially to emphasise. If I am right in my interpretation of the facts revealed by the [p. 32] observation of cutaneous sensibility during the regeneration of a divided and re-united nerve, the earlier and cruder kind of sensibility undergoes two different kinds of fate. Such elements as are serviceable are utilised when the later and higher forms of sensibility come into existence. These useful elements of protopathic sensibility become fused with epicritic elements to form the fully developed sensibility which is possessed by the normal skin. Utilisation by means of the process of fusion is the fate of the greater part of the complex body of processes which make up protopathic sensibility. It is only the smaller part which undergoes the other fate of suppression. It is only those features of early sensibility which are incompatible with later developments which are suppressed. Thus, the wide diffusion and distant reference of protopathic spatial sensibility are suppressed because, if they persisted, they would prejudice in the most serious manner the exact localisation and spatial discrimination of fully developed cutaneous sensibility. Again, the suppression of the painful element when the normal skin is stimulated with an object at 40° C.-44°C. takes place because this painful quality would interfere with the pleasant character of the normal heat sensation and with the discrimination which is normally possible at that temperature. In the case of cutaneous sensibility there has taken place a differentiation of treatment according as the earlier material could or could not be utilised in the interests of the higher purpose offered by the possibility of discrimination and graduation. Corresponding with this distinction two kinds of elements in the unconscious might be recognised -- those which have only disappeared from consciousness in their original form, but continue to exist in the different form they have assumed through the process of fusion, and those whose disappearance has been more complete so that they do not enter into consciousness even in an altered form under normal conditions, though their continued existence is shown by their reappearance under peculiar conditions such as those which accompany the regeneration of a divided and reunited nerve.
There is little doubt that a similar twofold possibility is also [p. 33] open in the case of other kinds of early experience. There is reason to believe that al kinds of early experience undergo transformations similar to those undergone by protopathic sensibility. According to this view certain elements of early experience are utilised and form, by fusion with other elements, the products which make up the experience of any later period of life. It is only elements of experience and modes of behaviour which are incompatible with these later developments which are suppressed.
It now becomes necessary to reconsider the sense in which we shall use the term "the unconscious." It would be possible to use it to include not only the fully suppressed elements, but also those which might be regarded as unconscious because they no longer exist in their original form but in the form they have assumed through their fusion with later products of mental development. It will, I believe, be convenient to limit the use of the term "the unconscious" to the former category, to those earlier forms of mental activity and mental experience which have not been capable of utilisation by the process of fusion, but have required the more drastic measure of suppression.
Footnotes