galvanic reflex results with some of the results obtained by Dr Mira of Barcelona on blood pressure changes following emotional stimuli, as shown by Pachon's method, and Dr Mira tells me that although he has not done so many observations his results on cases of mental disorder are of the same order as my psycho-galvanic experiments. It therefore seems probable that the reactivity of the skin is closely related to the reactivity of the autonomic nervous system as a whole, although the condition of the skin itself may account for local differences.

If it was only a question of autonomic reactivity then it might be possible to explain some of my results, the small reaction in cases of conversion hysteria as compared with the large reaction in cases of anxiety hysteria for example and the difference between the reactions of toughminded and tender-minded persons, on the assumption that those who gave a large response had an exaggerated sensitivity of the sympathetic nervous system, and the strength of the reflex in cases of hyperthyroidism would support such a view. And it might be that a small reflex corresponded with the 'vagotonic' disposition of Eppinger and Hess and a large reflex with a 'sympathicotonic' disposition.

But as Langley has shown the sympathetic system cannot give true reflexes without the intervention of the central nervous system and until we know more about the interaction between the autonomic and central nervous systems we cannot interpret our results satisfactorily. My experiments certainly suggest that the psycho-galvanic reflex is conditioned by the state of the cerebral cortex. In those classes of patients where we have definite evidence of cortical degeneration or maldevelopment there is only a very small or no reflex at all, in those cases where organic changes in the cortex are probable and also in conversion hysteria there is only a comparatively small reflex, and in others in whom there is no evidence of cortical change there is a much larger reflex. But healthy persons may give under different conditions a reaction which varies from one very much in excess of the average to one which is not much larger than that of an idiot. I noted in my review1 that the reactions in subjects of poor intellect, as evidenced by their low standard at school, were rarely so marked as in my intellectual subjects, and Miss M. D. Waller as a result of her investigations on seventy-three medical students, concluded that intellectual efficiency, as judged by examination results, was associated with higher nervous sensitiveness in the psycho-galvanic reflex. Although this is true all one can say is that a high reflex does not occur in those who are intellectually inefficient but a low reflex does not neces1 Brain, 1920, LXI. p. 69.

sarily indicate intellectual inefficiency. In a paper on the relation of the psychoneuroses to mental deficiency1 I showed the liability for those who had been in the lower standards at school to suffer especially from conversion hysteria and for those who had reached the higher standards to suffer from anxiety states. Amongst my military in-patients of those who had not reached higher than standard III, 82 per cent. suffered from conversion hysteria, whilst of those who had reached standard VII only 6 per cent. suffered from conversion hysteria and many of these were of the fixation hysteria type. The difference therefore in the galvanic response between the cases of conversion hysteria and anxiety states, which in other experiments, not carried out by the constant method and therefore not strictly comparable with this series, has been even more marked, may be due to some inherent lack of development of the cerebral cortex. That the failure of the galvanic reflex is not necessarily due to want of psychic elaboration of the stimulus is shown by the fact that in those cases, in whom the psycho-galvanic reflex is small or non-existent, the deflections due to physiological causes-coughing, yawning, etc.,are equally small or non-existent. One explanation of the absence of the reflex in cases of cortical degeneration would be to assume that the psycho-galvanic reflex was an associative reflex in Bechterew's sense, and that the visceral organs have a cortical representation as Bechterew has tried to show, but no further evidence has been forthcoming to support this view and most authorities seem to be against it.

Whatever the correct interpretation of the results may be we must regard the cerebral cortex as being an important factor in the determination of the psycho-galvanic reflex. And since Head and Holmes have shown the chief functions of the cortex to be of an inhibitory and discriminative nature, we are entitled to conclude that apart altogether from the question of autonomic reactivity the psycho-galvanic reflex will not occur unless the inhibitory functions of the cortex are stimulated. These results support the view which I tentatively put forward in a paper on "Suggestion and Suggestibility "2 that "the psychogalvanic reflex may be an indication of the contrary or epicritic forces stimulated by the liberated emotion, and that it is not merely an emotive response." That the state of the skin is merely conditioned by the state of the cortex might be a possibility, and perhaps the psycho-galvanic reflex experiments alone do not entitle us to assume anything more than that, but this would not account for the results of Dr Mira's experiments. And 1 E. Prideaux, J. of Neurology and Psychopathology, 1921, vol. II. no. 7. E. Prideaux, Brit. Journ. of Psychol. 1920, x. p. 228.

moreover the relation between the muscular expression and the visceral expression the fact that, when some central excitement is aroused and much muscular movement reflexly results, there is very little galvanic response whilst on the other hand the suppression by reflex inhibition of the muscular reflex is accompanied by a large galvanic responsepoints to the conclusion that it is the inhibitory functions of the cortex, which condition the reflex. We can probably allow that the psychogalvanic reflex is a criterion of the visceral changes consequent on emotion, though there may be specific visceral reactions in some people to specific emotions, as we know that each person has his particular predisposition.

So that we can infer that a psycho-galvanic reflex and therefore visceral changes occur when an instinctive impulse is aroused-that is physiologically when the optic thalamus is stimulated-and when at the same time the impulse is reflexly inhibited from within or stimulates the discriminating functions of the cortex, but we cannot say that the converse is true, that the absence of a galvanic reflex necessarily means a lack of inhibition, as it may also indicate a diminution of reactivity of the skin or autonomic nervous system.

We can say therefore in the case of the idiot that no visceral changes occur because of the lack of inhibitory functions of the cortex, or at any rate of some factor associated with it, but we cannot say this definitely. of the classical hysteric. When however the fact, that the average hysteric is shown to be of a lower mental development, is taken into account his lack of visceral response would appear to be due to the same cause.

And since we have found that visceral changes may occur without arousing an emotion, and that some central excitement can be aroused without producing visceral changes, we cannot infer that a person who gives no galvanic reflex experiences no kind of emotion. It would seem impossible to distinguish the central excitement properly belonging to an emotion from that which is merely instinct-feeling accompanying an impulse, but it seems certain that the emotion gains at any rate in intensity and duration from the consciousness of visceral sensations and that unless the central excitement is so reinforced it expends itself in the satisfaction of the impulse by muscular expression and leaves no feeling remaining which can be called an emotion. This central excitement part of the emotion is only momentary and disappears almost as soon as it is aroused unless it is reinforced by the visceral sensations. From this point of view it would appear that James and Janet were right in holding that the emotions of the hysteric were for the most part

artificial. And it would seem that these results justify my description of emotion given in an earlier part of this paper, that emotion is "a subjective feeling consisting of central excitement and visceral sensations, occasioned by situations which powerfully oppose or facilitate the aim of any instinctive impulse."

Summary.

(1) The term 'emotion' is used in this paper as a subjective feeling consisting of central excitement and consciousness of visceral sensations. (2) The James-Lange theory is untenable except in a very modified form.

(3) The psycho-galvanic reflex is in the same person at the same time and under the same conditions an indication of the intensity of crude emotions as subjectively experienced.

(4) There is considerable variation in the amount of the reflex in the same person at different times due to such causes as fatigue, alcohol, menstruation, etc.

(5) The psycho-galvanic reflex is not necessarily a criterion for comparing emotional reactions in different persons, unless we accept the James-Lange theory-taken by itself it only indicates the reactivity of the skin. But it seems to be a criterion of the amount of visceral sensations which are the concomitants of emotion and which reinforce what would otherwise be only a momentary excitement.

(6) The psycho-galvanic reflex is conditioned by the state of the cerebral cortex, but the relative parts played by the condition of the skin, the optic thalamus, and the reactivity of the autonomic nervous system have to be determined.

(7) In patients with definite cortical degeneration or maldevelopment the reflex is very small or non-existent, in cases where organic changes in the cortex are probable it is comparatively small, and in others in whom there is no evidence of cortical change it is much larger. (8) The view of James and Janet that the emotions of the hysteric are largely artificial is probably correct.

EMOTION AND EYE SYMPTOMS.

BY W. S. INMAN.

DURING the past fifty or sixty years it has been customary to regard errors of refraction as the cause of many symptoms of ill-health. Headache, tics, insomnia, inability to concentrate attention, photophobia, flushing and watering of the eyes, neuralgia, anorexia, constipation, anaemia, mental dullness, sleepiness and languor, squint, migraine, hysteria in many of its forms, are but a few of the troubles attributed directly or indirectly in modern English text-books to eye-strain. Some American ophthalmologists have been even more extravagant in their views, and claim to have cured scores of other ills by means of glasses. The mental and emotional state of the patient has not been considered, and the possibility of this state determining the eye symptoms instead of the eye condition causing the general manifestations appears to have eluded both oculist and physician. It is the object of this paper to show that the eye rarely produces other than ocular symptoms, unless the patient is emotionally unstable, and that he frequently is relieved, not by glasses, but by suggestion or else by some adjustment of the inner life usually unknown to the oculist.

Headache is the most common symptom for which patients seek relief from the ophthalmic surgeon. There are scores of thousands of people in this country alone who are wearing glasses, not for the purpose of seeing better, but solely to relieve headaches. In America, I believe, the practice is much more common. In France, on the contrary, it is rare. Are we to assume that the French suffer less from a given degree of eye-strain, and the Americans more? It must be remembered that the correction of errors of refraction is a modern invention. Astigmatism was hardly known, even by the medical profession, fifty years ago, and a hundred years ago probably no one wore glasses, except for old sight and pronounced degrees of hypermetropia and myopia. It is true that reading in those days, at any rate as we understand reading now, was rarely indulged in, but many occupations needed close attention to detail. Modern machinery, such as the sewing machine, has relieved the eyes of a great deal of strain. Either a large proportion of our forefathers suffered from chronic headache, or they were of a different breed from their