W.H.R.Rivers

“ With a given stimulus and an intact nervous system, the effect follows the cause with a simplicity and definiteness far more obvious than in the case of activity which is accompanied by consciousness. ”

“ 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. ”

“ They point out that this kind of reflex would be useless for the purpose of discrimination. The "mass-reflex " has a generalised character and shows an absence 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. ”

“ 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 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. ”

“ 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. ”

“ When by injury, disease, or operative procedure, the cortex cerebri has been put out of action, stimulation of the skin produces sensations characterised by a peculiar quality such as would be produced by over-weight of the affective aspect of sensation, very similar to that shown by protopathic sensibility. ”

“ When a part of the glans penis which is free from heat-spots is stimulated by a temperature of 40°C.-44°C. there is no sensation of heat, but only one of pain. This part of the body is normally devoid of epicritic sensibility, and the occurrence of pain on the glans, as the result of stimulation by heat, points to the pain on the thumb having been the result of the direct stimulation of that region by heat rather than an element of the referred cold. ”

“ Thus, removal of cortical activity does not produce radiation and reference of localisation because the suppression of these characters is still being maintained at the periphery.
Similar examples of suppression have been observed in the reflexes. In reflex action a movement takes place in response to stimulation which depends on a highly-organised and strictly-determined physiological mechanism. ”

“ Moreover, these spatial features of protopathic sensibility do not disappear entirely, but persist in a latent form ready to come again into consciousness if the appropriate conditions are present. This was well illustrated by certain experiments made shortly after the return of epicritic sensibility. [3] At this time, when radiation and reference were completely absent at the ordinary temperature of the room, they could be again brought into existence by cooling the limb. ”