In a general review of the neuroses as a whole the conclusion to which most people arrive at is that there is a want of adaptation both in respect of the environment as a whole and of the particular aspects of the personality. Such adaptation essentially depends on the establishment of cortical function at its highest level and neurotic symptoms unquestionably correspond to an interference with this function. These highest functions may be summarised as control, integration, discrimination and reference in time and space, all these are noticeably deficient in the neurotic. I believe that in the production of these symptoms various factors are responsible. In the first place there is a constitutional factor which may be expressed in Janet's terminology of a lack of psychological synthesis. For descriptive purposes this term could scarcely be bettered but it has been much criticised on the ground that it gives no explanation and is merely defining a condition in terms of Greek words. Such failure of proper integration of the engrams into stable entities may be due to temperamental influences especially in relation to the ductless gland secretion. Secondly having started with the constitutional factor in a greater or less degree the pleasure principle or the pursuit of gratification of inherent primitive impulses can less readily adapt itself or overcome the reality principle since there is a less stable and less integrated inherent pattern to oppose to reality. This leads to conflict and with conflict the continual arousing of fear in its most primitive form. It is clear that people differ in the degree of constitutional abnormality. At one end of the scale are those who can cope with no conflict between pleasure and reality principles and at the other those who only succumb when this conflict is of the most intense and insoluble nature. Although many of these conflicts involve the sex impulse this does not alter this contention, for in ultimate analysis the true root of the conflict is found. to be in the most primitive or regressed type of sex activity namely, Narcissism. In this latter state the sex feeling being directed to the individual himself, a thwarting of sex is equivalent to, if not identical with, a threat to the individual and one result of this latter type of stimulus is the experience of fear or anxiety. This seems to be the explanation of the occurrence of fear or anxiety as the emotional accompaniment of conflicts which are palpably of a sexual nature. Thirdly as a result of these unresolved conflicts fatigue is engendered and this will still further interfere with cortical function and so intensify the symptoms.

To return to the normal engram which subserves the fear reaction, we have seen that this is a complicated arrangement involving both the central nervous system and the sympathetic system. The function of

the latter is to prepare the body in every way for instant action, in many cases flight. In the well-organised engram which is not interfered with or conditioned by other engrams responding to simultaneous stimuli, such flight or other activity will immediately ensue. Even in normal subjects however when this immediate action is impeded by the activity of another engram say that subserving curiosity, there would appear to be a failure of discrimination and control and higher cortical centres being in abeyance there is a short circuiting at the level of the basal ganglia so that uncontrolled activity in the shape of tremor occurs. In this condition we find both agonist and antagonist muscles held in increased postural tone ready for action, but in the absence of cortical discrimination function, neither relaxes to allow the other to act. It is suggested therefore that the muscular rigidity is rather a concomitant than a causal factor of the tremor. When cases are cured by mere reeducation in relaxation of the muscles we are probably dealing with a condition of phobia of the tremor as described by Meige and when the muscles are relaxed by the restoration of cortical discrimination there is also a re-establishment of control over the striate centres so that the tremor ceases and the phobia is removed. In the ordinary neurotic the fear reaction is not subserved by a well-organised engram ready for prompt response as we have seen because of his constitutional temperamental qualities, hence the cortical control is never at its best and the establishment of the short circuiting thalamic-striate, fear-tremor response is easy and frequent.

The nature of the tremor will depend on the levels unmasked in the devolutionary process of removal of control. Where cortical control only is in abeyance whether from the fear reactions in the anxiety states or from fatigue in the true neurasthenic, there will be a fine tremor simulating the toxic tremors. When striate control is removed there will be coarse tremors as in the pseudo-Parkinsonian syndrome, not uncommon in hysterics. Where still lower controls such as those of the cerebellum are removed, there will be incoordinations such as occur in organic interference with the afferent side of the prespinal arc. In addition to this however tremors will be modified by the process of conditioning. For example in the masturbatory tremor referred to above. At first two separate engrams were involved. In the first a sexual stimulus, probably ideational, set off activity in an engram which subserved certain muscular movements of the hand in contact with the genital organ accompanied by sexual feeling and finally orgasm. Secondly, orgasm acted as a stimulus to a fear reaction which being poorly organised

easily became a fear-tremor syndrome. From being consecutive in their activity these engrams became coincident and the sex stimulus set off activity which subserved a fear feeling rather than a sex feeling and the motor activity became a masturbatory tremor. This analysis is superficial for the sake of clarity, for it omits the regression to narcissism which undoubtedly occurred.

In this way it would seem all neurotic tremors may be explained as to their nature, but the step in the argument which has not been touched upon is, what is the factor either hereditary or acquired which is responsible for the ease with which cortical control is inhibited and the thalamic striate short circuit allowed to develop? Any effort to explain this must be highly speculative, but it is suggested that irregularity in the suprarenal secretion is the factor responsible. Inhibition is generally held to be due to some biochemical change at the synapses and if we are to explain the variations in inhibitions and facilitations we must postulate a specific action of the biochemical inhibitive agent on certain synapses. Such specific action is familiar in pharmacology through the well-known actions of drugs on nerve endings. In the fear reaction it has been experimentally shown by Cannon that there is a large output of adrenalin into the blood, if this is excessive the secondary reactions of fear depending on sympathetic activity are excessive and uncontrolled and at the same time tremor occurs. This is at least suggestive that excessive suprarenal activity may result in inhibition of certain cortical control and so account for the symptoms. It may therefore be that the "failure in psychological synthesis" in the constitutional neurotic depends on an excess of suprarenal secretion in the temperamental balance and both this asynthesis and the Freudian conflict may be dependent on this, rather than the former be dependent on the latter. This may also explain the somewhat anomalous results of those who depend on exhibition of suprarenal and other extracts in the treatment of the neuroses. It is clear that if there is an inherent irregularity in this secretion there are likely to be periods of failure and over-secretion and consequently occasions when the exhibition of the extract itself or of its antagonists may work wonders in restoring cortical control. However in the present state of our knowledge there is bound to be somewhat of a hit or miss process and more exact knowledge is required as to when and for how long such extracts should be administered. Finally as to the process of cure of tremors. In general the cure of neurotics involves a restoration of full cortical function. They are enabled to discriminate, so that their table of values is re-established, they are enabled to control

so that their reactions are adapted to circumstances instead of always being of the all or none type. They integrate their experiences so that the tendency to regression and devolution is overcome. They regain the power of reference in time and space so that the affective reactions are properly oriented and are referred to actual occurrences at such and such a time and in such and such a place. In the same way in the motor system cortical control may be re-established so that striate mesencephalic and cerebellar centres are again brought to subservient function and agonist and antagonist muscles are again regulated in reciprocal activity. How this is done will depend on the case and on the pathogenesis of the tremor. Where simple fatigue is the predominant factor in the true neurasthenic rest may effect the cure. This will be the case when the patient is suffering from pure overwork or where there is a temporary conflict between the individual and a transitory modification of his environment. Shelter from his trouble till such modification has passed away may be all that is necessary. Similarly where tremor from incoordinated muscles and fear of tremor are the only abnormalities, reeducation in relaxing the muscles will be all that is required. But when there is endopsychic conflict, where the personality is divided against itself then these simple methods are not enough and an emotional readjustment is necessary by suggestion or better by analysis and resynthesis. The essence of the cure however is the resynthesis on the cortical level. This may be done by the patient himself after analysis has freed him so that he is given clean bricks with which to rebuild if this analogy is permissible. Or he may require assistance in his rebuilding, but it is necessary first to make sure that his bricks are clean. At present all that can be said of endocrine therapy is that it may be a useful adjuvant in re-establishing cortical function, but so far our knowledge does not allow us to dogmatise, in spite of the handbooks which instruct us how to cure all diseases by the appropriate hormone. Perhaps it is fortunate that most of them are inert.

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