Home     Boris Sidis Archives     Table of Contents



Boris Sidis, Ph.D., M.D.

Boston: R. Badger, 1914




            In Folia Neuro-Biologica, Band VII, 1913, T. Brailsford Robertson advances an interesting physiological theory as an explanation for the concomitant physiological manifestations of consciousness in general and of hypnosis in particular. I quote Robertson at some length so that the reader should have a clear idea of the hypothesis. Of course, the hypothesis is only provisional and helps the reader to the conception of a possibility of picturing to oneself the physiological and chemical processes concomitant with the phenomena of consciousness, normal and abnormal. Our data of the physiological processes concomitant with mental activities are so scanty and vague that the best that can be done is to stick to facts and describe mental phenomena in terms of consciousness:

            “The chief value of the experimental evidence which has so far been presented lies in the fact that in every detail it goes to support and confirm the theoretical reasoning which, apart from this evidence, has led us to infer that the processes which underlie and determine the activities of the central nervous system (and therefore the physical correlates of mental phenomena) are autocatalysed chemical reactions.

            “We may however, approach the question experimentally from an entirely different point of view and in this way acquire evidence of a much more general character. As we shall see, the evidence thus acquired emphatically supports the conclusions already arrived at or indicated in the diverse ways enumerated above.

            “The time-relations which are displayed by autocatalysed chemical reactions are in the highest degree characteristic and have been very extensively studied. All ordinary reactions at constant temperature whether catalysed or uncatalysed, continuously and regularly fall off in velocity from the moment at which they begin. Autocatalysed reactions, on the contrary start relatively slowly, but, as the initial stages of the reaction liberate more and more of the catalysor, they proceed more and more rapidly until a point is reached at which the decrease in the active mass of the reacting substance balances the increase in the active mass of the catalysor and the velocity of the reaction progressively decreases. The only other reactions, so far as our knowledge extends at present, which display positive acceleration, that is, which increase in velocity as they proceed, are certain catenary reactions, that is, reactions which proceed in two or more stages. Autocatalysed reactions may, however, be distinguished from catenary reactions by their symmetry. In the majority of autocatalysed reactions the first half of the reaction, during which the velocity is increasing, occupies the same period of time as the second half, during which the velocity is decreasing. Catenary reactions on the contrary, are not symmetrical; the period of time occupied by the first half of the reaction bears no simple relation to the period of time occupied by the second half of the reaction.

            “If, now, the chemical processes which underlie the activities of the central nervous system are autocatalytic in nature, then we should expect to find, among the time-relations of these activities, the highly characteristic time-relations which distinguish an autocatalysed chemical reaction and, in point of fact, as I have else-where shown, the relationship which subsists between the number of meaningless syllables memorised and the time spent in learning them is that which is characteristic of the progress of an autocatalysed chemical reaction. Similar time-relations are displayed in the performance of other forms of intellectual effort, and the Weber-Fechner law of perception is directly deducible from the assumption that the central processes which underlie and determine the rate of perception are auto-catalytic.

            “It is in the performance of the neuro-muscular response to a simple volition, however, such as that involved in drawing a straight line that these time-relations are exhibited in their simplest form. By means of a device originally employed by Loeb and von Koranyi, I have measured the relationship between the time (estimated from the inception of movement) and the distance moved over by the hand in drawing a straight line at a fair rate of speed.

            “The time-relations which are displayed in this process are identical with those which are displayed by an autocatalysed chemical reaction. The symmetry of the relations renders it very unlikely that catenary reactions play any appreciable part in determining the rate of the neuro-muscular response.

            “Upon the threefold basis which we have thus briefly reviewed of Deduction and of Direct and Indirect Experimental evidence we may venture, I think, with a fair measure of confidence, to erect the working hypothesis that the processes which underlie and condition the various activities of the central nervous system are, primarily, autocatalysed chemical reactions. The utility or non-utility of this hypothesis in the further elucidation and correlation of the activities of the central nervous system may be trusted to justify or condemn its employment. I am about to show that this hypothesis enables us to correlate in a satisfactory manner the various phenomena encountered in hypnosis and in allied conditions, both with one another and with the more familiar phenomena of perception, memory, etc.

            “Adopting the working hypothesis outlined above we perceive that the canalisation hypothesis of Exner can now be expressed in a much more definite and concrete form. Each incoming stimulus carves out for itself or deepens a pre-existing channel in the central nervous system, but the channel is not a trough formed by the physical displacement of particles, it is a chemical channel, a thread or trace of the autocatalyst of central nervous activities, a thread which need not necessarily be supposed to be more than a few times the diameter of “the sphere of molecular influence” in width. This deposit necessarily follows faithfully the path pursued by the original impulse and permits succeeding impulses to pass over the same path more readily by virtue of its presence. It is possessed, of course, of a definite spatial location, but, and this is a very important point, if by any chance it should be obliterated or destroyed it is not irreplaceable even if the continuity of the original path be forever interrupted. For it is only one of a conceivably enormous number of paths which might be traversed by a stimulus in its passage from one extremity of the original path to the other. It is not localised in the sense that Ziehen’s and Munk’s hypothetical material images are localised, irrevocably and unalterably anchored to one spot.

            “Furthermore, this tract is capable of being traversed by other subsequent or preformed traces in as may different ways as the axons and ganglion-cells of the central nervous system intercommunicate, that is, so far as our knowledge extends, in a number of ways which, for all practical purposes may be regarded as infinite.

            “It must always be remembered that the trace consists of a deposit of an autocatalyst which we are obviously compelled to assume is an autocatalyst for the propagation of all impulses. It follows therefore that if a faint trace runs into, that is to say traverses or intersects a well-marked trace, there will be a tendency for the impulse forming or following the faint trace to be deflected completely or in great part into the well-marked trace. Indeed if the intersecting trace be sufficiently well marked and formed subsequently to the faint trace we can see how impulses now arriving by way of the faint trace would become so largely deflected into the new, well-marked trace as to leave the parts of the faint trace remote from the point of intersection almost untraversed by any impulses at all. Instances of the mental correlates of these psycho-chemical phenomena abound in our daily psychic life. For the sake of illustration, however, we may instance the ability of certain voluntary muscular efforts such as that of clenching the teeth to inhibit the otherwise involuntary motor expression of pain. In terms of our hypothesis we may translate this phenomenon as follows: The continuous stream of powerful impulses necessary to maintain the muscular effort canalises a trace sufficiently well-marked to deflect a proportion of impulses which would otherwise find their way to the traces which are conducting the impulses which condition the motor expression of pain. Another example is afforded by the fact that when the diffused activity of the central nervous system is limited and impulses are confined to restricted areas they tend to follow faint traces from which they would otherwise become deflected were the content of consciousness larger. The phenomena which accompany the formation of habits and the manner in which one habit may supplant and obliterate another afford a multitude of examples of the effects of “deep” canalisation in confining or diverting the impulses arising from our sensory impressions.

            “Again it is evident, since memory traces unquestionably albeit slowly fade, that traces slowly and spontaneously tend to become fainter and fainter with disuse. The autocatalyst evidently tends to dissappear (diffuse?) from the region in which it has been deposited. From what has been said above it appears, therefore, that two regions of the central nervous system might become almost entirely isolated, blocked off from one another, owing to the sheer “depth” of certain channels in each region deflecting all impulses into well-worn pathways that would otherwise strike across the intervening faintly-channelled region and establish a communication between the two regions (contents of consciousness.) We are here forcibly reminded of the now well-known phenomena of double and multiple personality and we are led to attribute the physical correlates of these phenomena to simultaneous excessive canalisation in one or more regions of the central nervous system.

            “Sidis (“The Psychology of Suggestion” New York 1911 pp. 160 et seq.) lays in instances of dual personality considerable stress upon the fact that one of the personalities usually embraces a wider content of consciousness than the other (the “primary” personality) inasmuch as the secondary personality usually contains recollections belonging to the primary personality while the primary personality does not contain recollections belonging to the secondary personality. In such a case the primary personality evidently represents the result of confinement of the area of cerebral activity to certain deeply canalised regions which are usually those which are customarily active in the “normal” psychic life of the individual in question. The secondary personality would represent the result of an overflow of impulses into regions not “normally” traversed. Transition from the primary to the secondary personality would occur whenever a stream of impulses intersects one of the (possibly very few) “channels” connecting the “normal” with the “abnormal” region. The stream of impulses would then divide itself, until diverted into some exceptionally “deep” channel in the primary region, into two parts both of which would be represented in the psychic life. On the other hand, if the secondary area becomes “deeply” channelled, it may draw off the stream of impulses completely from the primary and the condition of primary and secondary consciousness may alternate without either personality containing recollections belonging to the other. An instance of this type of dual personality is afforded by the Hanna case.

            “The instability of “secondary” personalities is also readily understood; as the trace-system connected with an “abnormal” deeply canalised region grows in extent and diversity it tends more and more to encroach upon and traverse other deeply-canalised areas which may belong to the “normal” psychic life or to other “abnormal” areas; sooner or later effective connection will be established, impulses formerly confined to the “secondary” trace-system will be deflected wholly or partially into others and the “secondary” personality loses its outline and disappears.

            “Again:—Supposing that the stimuli which impinge upon the central nervous system through the agency of the senses, or, indeed, through the spontaneous diffused activity of the central nervous system itself, be by some means so limited and suppressed that for all practical purposes all impulses arriving through the senses are for some time discharged along one pathway only; there will obviously be a tendency for that pathway to become deeply canalised, while at the same time other pathways leading from the sense-organs will be becoming progressively fainter and fainter. The subsequent tendency will be, until new pathways are forcibly channelled out, for the activities of the central nervous system (field of consciousness) to become limited and narrowed to this single channel. We are at once reminded of idées fixes, of the insensitiveness to disturbance of one who is deeply engaged in the elucidation of some specific problem, and of the more exaggerated phenomena of sensory hallucinations, automatic and uncontrollable impulses and of the phenomena of hypnotic and post-hypnotic suggestion. We are led to inquire whether the circumstances attending the formation of these idées fixes correspond in any way with the theoretical conditions just outlined.

            “According to Sidis, whose genius for experimental investigation has done so much to enlarge our knowledge of this difficult field, the conditions leading to hypnosis (which he defines as a condition of abnormal suggestibility) are the following:—

            1. Fixation of Attention.

            2. Monotony.

            3. Limitation of voluntary movements.

            4. Limitation of the field of consciousness.

            5. Inhibition (of the diffused activity of the central nervous system.)

            “The exact correspondence between the theoretical conditions which should, ex hypothesis, lead to a condition of relative automatism and the experimental conditions which are found to lead to the condition of hypnosis is patent.

            “The testimony of other observers all points in the same direction, namely, that limitation of the field of consciousness, confinement of impulses to as few and as limited channels as possible, is the prime condition fostering the onset of hypnosis and the conversion of the otherwise unpredictably and multifariously active central nervous system into the mediator of more or less automatic responses to stimuli. Thus Moll states:—

            “Those who can by no possibility fix their attention, who suffer from continual absence of mind, can hardly be hypnotised at all. If he sufficiently concentrates his attention; if he gazes at some object with the necessary attention, then hypnosis may be produced at the first attempt, even against the wish of the persons experimented upon.”

            “Bernheim approaches the view which I have developed very closely in the following passage:—“We also know that subjects who have been hypnotised often may contract an increase of this ideo-reflex excitability through habit, that is to say, through the frequent repetition of the phenomena induced; the paths most frequently followed present the easiest and most rapid way of diffusing the nervous force, the impression follows these paths from preference even in the waking condition; and for this reason subjects trained and educated by former hypnotisations may manifest the same phenomena and carry out the same acts under the influence of all-powerful suggestion.”

            “The analogy between reflex-action and induced psychic automatism has been frequently pointed out. From what has preceded it will be clear to the reader that in terms of our working hypothesis reflexes are to be regarded as attributable to a canalisation between the sense-organ and the organ of motor response which is so intense as to constitute complete isolation of the reflex-path in so far as any possible deflection of the impulse is concerned. Instincts we may regard, with Fabre and Loeb, as consisting in concatenated chains of reflexes, each link in the chain being evoked by the previous link and affording the stimulus which calls into activity the succeeding link. In some instances, however, in response to the repeated assault of novel environmental conditions, the canalisation at some stage in the process may not be sufficiently deep to prevent some degree of deflection of the impulses, and under these circumstances instincts, even in animals whose life appears totally automatic, may become perverted and unpredictable results may ensue.

            “The various conditions of heightened suggestibility accompanying hypnotic and allied states are to be regarded as intermediate stages of canalisation lying between the excessive degree of canalisation which conditions reflex and instinctive automatisms and normal, equably balanced and diffused activity of those portions of the central nervous system which condition our voluntary acts and thoughts, i.e., our fluctuating, non-predictable reactions to environmental changes. Habits constitute yet another group of members of the doubtless infinite series of gradations stretching from diffused unpredictable activity to the rigidly constrained reflex responses of the lower animals or of our involuntary neuro-muscular apparatus.

            “I have already dwelt upon the fact that the canalisation-hypothesis permits us to account for the physical correlates of double and multiple personality, because excessive canalisation in any region would tend to isolate that region from any other deeply canalised region in the central nervous system, since all impulses would tend to be drawn off and assimilated into one or other of these regions. We have now to re-examine this point because it has a strong bearing upon the “disaggregating” action of hypnosis which has been so clearly demonstrated by Sidis and his co-workers. I quote from Sidis:

            “Hypnosis, we may say, is the more or less effected disaggregation of the controlling inhibitory centers from the rest of the nervous system; along with this disaggregation there goes a dissociation of the controlling guardian consciousness from the reflex organic consciousness. Dissociation is the secret of hypnosis, and amnesia is the ripe fruit.

            “The magnitude of this disaggregation greatly varies. If it is at its minumum the hypnosis is slight, if at its maximum the hypnosis is deep and is known as somnambulism.

            “From our standpoint of hypnosis we may say that there are only two great distinct classes of hypnotic states:—

            1. Incomplete dissociation of the waking, controlling consciousness.

          2. Complete dissociation of the waking, controlling consciousness. Stating the same somewhat differently we may say that there are two states:—

            1. Incomplete hypnosis accompanied by a greater or lesser degree of memory.

            2. Complete hypnosis with no memory.

            In other words hypnosis has two states:—

            1. The Mnesic state.

            2. The Amnesic state.

            “Amnesia is the boundary line that separates two different hypnotic regions.” (Psychology of Suggestion, pp. 70-71).

            Robertson thinks that his view of bio-chemical traces disagrees with my theory of neuron disaggregation. As a matter of fact, as he himself admits, the two theories are interchangeable. Aggregations and disaggregations of systems of traces do not in any way differ from aggregations and disaggregations of neuron systems. They are convenient hypotheses for the physiological expression of normal and abnormal phenomena of mental life.

Boris Sidis Archives     Contents