In the organization of our military forces in 1917, when this country entered the war, every effort was made to take advantage of the experience of others. Of the men returned to Canada from European battlefields on account of disability, the nervous and mental cases contributed ten per cent of the total at that time, as was shown by Farrar.[90] These were distributed as follows:—neurotic reactions, fifty-eight per cent; mental disease and defect, sixteen per cent; head injuries, fourteen per cent; epilepsy and epileptoid conditions, eight per cent; and organic diseases of the central nervous system, four per cent. The first group mentioned consisted of neuroses in general and included the so-called cases of "shell shock," which brings us to one of the most interesting problems of the war. Dean A. Worcester, in a recent letter to the editor of Science, has raised the question as to whether this is a new disease. He calls attention to the following reference by Herodotus to the Battle of Marathon which occurred in the year 490 B.C.:—"The following prodigy occurred there: An Athenian, Epizelius, son of Capliagoras, while fighting in the medley, and behaving valiantly, was deprived of sight, though wounded in no part of his body, nor struck from a distance; and he continued to be blind from that time for the remainder of his life. I have heard that he used to give the following account of his loss. He thought that a large, heavy armed man stood before him, whose beard shaded the whole of his shield; that this specter passed by him, and killed the man that stood by his side. Such is the account I have been informed Epizelius used to give."
The nature and cause of shell shock has been the subject of much controversy. In 1875 Ericksen called attention to the effect of intense emotional shock on the nervous system. This he explained as "dependent on molecular changes in the cord itself." Oppenheim's monograph in 1899 was responsible for the general use of the term "traumatic neurosis." His conception of these conditions was not accepted by Charcot, who at the time insisted that they belonged to the domain of hysteria, and were due solely to psychic traumas. Oppenheim's[91] observation of cases during the first year of the war confirmed his previous views. He expressed the opinion in 1915 that "in absolutely healthy and mentally normal individuals, without any trace of hereditary taint, war trauma may cause psychoses or neuroses. The causal injury may be of an objective, psychic or mixed nature. Violent detonations illustrate the mixed type. Their effect upon the nerve of hearing is certainly physical, but the psychic effect—terror—is also an important element in the resulting condition. The enormous air pressure exerted by the close passage of these missiles is another influential factor. An element that tends to complicate etiology is the frequent long duration of the exciting causes (prolonged and continuous artillery fire, a series of injuries received at brief intervals, exhaustion from various causes, lack of sleep, insufficient nourishment, extreme heat or cold, etc.)." He admits that the symptoms indicate a combination of neurasthenic and hysterical complexes which may be explained on a psychogenic basis, but maintains that the war has demonstrated them to be of a different nature. An external shock causes "a functional disturbance of the delicate mechanism of the psychic centers shown in 1, faulty distribution of motor impulses, 2, hypo-innervation, 3, hyper-innervation, causing tremors, tonic and clonic spasms, etc., instead of single muscle actions." He admits that a hysterical temperament may be an important factor. Max Nonne [92] in 1915 called attention to the fact that conditions combining symptoms of hysteria, neurasthenia and hypochondriasis plus vasomotor changes may occur without any history of injury and should not be called traumatic neuroses for that reason. He felt that the sudden recoveries occurring so frequently strongly discredited any theories suggesting an anatomical basis. He expressed the opinion that the most common cause was the explosion of hand grenades and that the main factor involved was an emotional disturbance. Binswanger[93] was of the opinion that mechanical injuries to the nervous system were responsible for the clinical pictures in war hysterias. He found that in a few cases only was there a history of predisposition, and maintained that in pre-war conditions hysteria was the result of a combination of psychic traumas with physical disturbances. Exciting causes were "over-exertion, irregular and insufficient nutrition, loss of sleep and high mental tension." He concludes that "The theory of a psychic mechanism as the origin of these motor and sensory symptoms is not demonstrable." "War neurology has demonstrated that emotional shock, in conjunction with other injuries, may cause a symptom complex identical in all its details with the well known clinical picture of hysteria." Wolfsohn,[94] from a study of one hundred psychoneuroses and one hundred cases of physical injury received on the firing line, reached the conclusion that war neuroses are very rarely associated with external wounds. The vast majority of cases studied had a neuropathic or psychopathic taint, as shown in the family history in fourteen per cent of the total. A previous neuropathic constitution in the patient was found in seventy-two per cent. "A gradual psychic shock from long-continued fear, together with the sudden change from quiet, peaceful environment to the extraordinary stress and strain of trench fighting, is the chief predisposing cause of war psychoneurosis in soldiers with neuropathic predisposition.... Wounded soldiers do not suffer from war neuroses except in rare instances."
When the United States entered the war, Major, afterwards Colonel, Thomas W. Salmon[95] of the United States army made an exhaustive study of "The Care and Treatment of Mental Diseases and War Neuroses ("Shell Shock") in the British Army." At that time one-seventh of all discharges for disability from the British forces were due to mental and nervous disorders. As a matter of fact, they accounted for one-third of all discharges for actual diseases (eliminating wounds). England with the advantage of three years of experience had presumably completed her organization to its highest efficiency. One and one-tenth per cent of the cases in the military hospitals were suffering from mental diseases. The percentage represented by the expeditionary forces was 1.3. About six thousand "shell shock" cases were being admitted annually to the English hospitals. Col. Salmon estimated the admission rate at two per thousand in the troops at home and four per thousand in the expeditionary forces. The civilian rate during the same period was about one to one thousand of the population. The confusion which existed early in the war was shown by the fact that ten per cent of the cases sent to the Red Cross Military Hospital at Maghull as war neuroses turned out to be insane and twenty per cent of those admitted as mental cases at the Royal Victoria Hospital at Netley were subsequently found to be suffering from neuroses. The first conclusion reached by Col. Salmon was that "contrary to popular belief and to some medical reports published early in the war, no new clinical types of mental disease have been seen in soldiers. There are no war psychoses." He found that of the cases being admitted to the hospitals for mental diseases about eighteen per cent were mental defectives, two per cent syphilitic psychoses, twenty per cent manic-depressive insanity, fourteen per cent dementia praecox, and seven per cent epilepsy. Statistics at that time were not available on purely psychopathic conditions, owing to the classification used.
In discussing the etiology of shell shock Col. Salmon divides those conditions into four groups—1. Cases in which death is caused by exploding shells or mines without external signs of injury; 2. Those in which severe neurological symptoms follow burial or concussion by explosions, with characteristic syndromes suggesting the operation of mechanical factors; 3. Cases in which there may or may not be damage to the central nervous system, but showing neuroses similar to those of civil life—"In this group of cases, in which there is possibility but no proof of damage to the central nervous system, the symptoms present which might be attributable to such damage are quite overshadowed by those characteristic of the neuroses;" and 4. Cases in which even the slightest damage to the central nervous system from the direct effect of explosions is exceedingly improbable. He also found that hundreds of men who have not been exposed to battle conditions at all develop symptoms almost identical with those described as "shell shock," many occurring in the non-expeditionary forces. The psychogenic factors involved are very well summarized by Col. Salmon in the following words:—"The psychological basis of the war neuroses (like that of the neuroses in civil life) is an elaboration, with endless variations, of one central theme: escape from an intolerable situation in real life to one made tolerable by the neurosis. The conditions which may make intolerable the situation in which a soldier finds himself hardly need stating. Not only fear, which exists at some time in nearly all soldiers and in many is constantly present, but horror, revulsion against the ghastly duties which must be sometimes performed, intense longing for home, particularly in married men, emotional situations resulting from the interplay of personal conflicts and military conditions, all play their part in making an escape of some sort mandatory. Death provides a means which cannot be sought consciously. Flight or desertion is rendered impossible by ideals of duty, patriotism and honor, by the reactions acquired by training or imposed by discipline and by herd reactions. Malingering is a military crime and is not at the disposal of those governed by higher ethical conceptions. Nevertheless, the conflict between a simple and direct expression in flight of the instinct of self-preservation and such factors demands some sort of compromise. Wounds solve the problem most happily for many men and the mild exhilaration so often seen among the wounded has a sound psychological basis. Others with a sufficient adaptability find a means of adjustment. The neurosis provides a means of escape so convenient that the real source of wonder is not that it should play such an important part in military life but that so many men should find a satisfactory adjustment without its intervention. The constitutionally neurotic, having most readily at their disposal the mechanism of functional nervous diseases, employ it most frequently. They constitute, therefore, a large proportion of all cases but a very striking fact in the present war is the number of men of apparently normal make-up who develop war neuroses in the face of the unprecedentedly terrible conditions to which they are exposed."
The symptomatology has been briefly summarized by Col. Salmon in a way which cannot be improved upon:—"Most of them can be summed up in the statement that the soldier loses a function that either is necessary to continued military service or prevents his successful adaptation to war. The symptoms are found in widely separated fields. Disturbances of psychic functions include delirium, confusion, amnesia, hallucinations, terrifying battle dreams, anxiety states. The disturbances of involuntary functions include functional heart disorders, low blood pressure, vomiting and diarrhea, enuresis, retention or polyuria, dyspnoea, sweating. Disturbances of voluntary muscular functions include paralyses, tics, tremors, gait disturbances, contractures and convulsive movements. Special senses may be affected producing pains and anesthesias, mutism, deafness, hyperacusis, blindness and disorders of speech. It is highly significant that, in this unprecedented prevalence of functional nervous diseases among soldiers, no symptoms unfamiliar to those who see the neuroses in civil life present themselves."
An analysis of the 170,000 cases discharged for disability in England showed that twenty per cent were due to war neuroses. In his second Lettsomian lecture Mott[96] called attention to the interesting similarity between shell shock following concussion and burial, and the symptoms resulting from an acute carbon monoxide poisoning. This was, of course, a very possible complication in trench warfare. The headache, ringing in the ears, blurred and indistinct vision, hallucinations of sight, or actual blindness, giddiness, yawning, weariness, vomiting, cold sensations, palpitation, sense of oppression on the chest, etc., so common in gas poisoning are often followed, when consciousness is regained, by confusion and loss of memory, with retrograde amnesia. Tremors and loss of speech are also frequently noted. Mott reached the conclusion that shell shock, in some cases at least, was due to gas poisoning. In his third Lettsomian lecture he discusses the symptomatology of shell shock. In some instances there was a partial loss of consciousness, characterized by dazed states somewhat similar to those of epilepsy. Under speech defects he includes mutism, aphonia, stammering, stuttering and verbal repetition. Headache in the occipital region was found to be a very common symptom. Vasomotor conditions were palpitation, breathlessness, pericardial pain, rapid weak pulse, low blood pressure, cold extremities, low temperature, etc. Anesthesia and hyperesthesia or loss of pain sense also occurred, and deafness was often observed. Smoky vision, photophobia and functional blindness were frequent eye symptoms. Tremors, tics, choreiform movements, functional paralysis and gait disturbances are also mentioned by Mott. In the Chadwick lecture he later called attention to the presence of insomnia and terrifying dreams in practically all cases of true shell shock.
In 1917 Mott[97] reported the examination of the brains from two cases of pure shell shock. They showed a congestion of the meninges, scattered subpial hemorrhages, and congested vessels in the internal capsule, pons and medulla. In one case there was an extravasation of blood into the substance of the lower surface of the orbital lobe. He spoke also of a general chromatolysis in the ganglion cells. Eder[98] in 1917 advanced the theory that the symptoms of neuroses are the result of mental conflicts and that the mechanisms involved are those attributed by Freud to hysteria. As a result of an analysis of one hundred cases he reached the conclusion that mechanical shock, gas poisoning and other physical traumas were not factors in the production of these conditions. His cases occurred in persons free from hereditary or personal psychoneurotic predisposition. Chavigny in a discussion of the mental diseases in the French army asserted that psychoses and neuroses were practically unknown until trench warfare began and the use of heavy artillery became common. From this moment psychiatric units became necessities. Ballet and de Fursac[99] were very firmly of the opinion that shell shock was due to purely emotional reactions in predisposed individuals. "If disturbances from explosion and from emotional shock, existing with or without traumatism, produce identical results, it is evident that they have a common factor and this common factor can be only the emotion itself. Disturbance from explosion without external injury presupposes an emotional state, and it is from this state that it derives its causal efficacy; whatever the etiological complex found as the cause of a condition of shock, whether the explosion of a shell, bomb or mine, the sight of the dead, burial in a trench, wound from an explosion or a missile, there is only one factor of importance, the emotional factor, which is essentially responsible for all the neuropsychic disorders that together make up the shock syndrome."
In 1915 Birnbaum summarized seventy-two articles written on war psychoneuroses in the German army up to the middle of March of that year. On analyzing this study Hoch reached the conclusion that the rate of psychoses was only about two in ten thousand, which would appear to be entirely too low. Birnbaum compared the statistics of various observers showing the frequency of psychoses during the first year of the war as follows:—"Psychopathic constitution, hysteria, traumatic neuroses, etc., Bonhöffer, fifty-four per cent; Meyer, 37.5 per cent; and Hahn forty-three per cent. Alcoholism, acute and chronic, Bonhöffer, ten per cent; Meyer, 21.5 per cent; and Hahn, twenty-one per cent. Dementia praecox, Bonhöffer, seven per cent; Meyer, 7.5 per cent; and Hahn, thirteen per cent. Epilepsy, Bonhöffer, fourteen per cent; Meyer, 11.5 per cent; and Hahn, eight per cent. Manic-depressive insanity, Bonhöffer, three per cent; Meyer, four per cent; and Hahn, two per cent. General paralysis, Bonhöffer, six per cent; Meyer, 3.5 per cent; and Hahn, three per cent." In discussing these findings Hoch says:—"It is clear from this table that psychopathic constitutions, various psychogenic reactions, hysterical and anxiety states, also exhaustive conditions—all of which are included in the first group—are strikingly frequent; whereas the more serious constitutional disorders, such as manic-depressive insanity, dementia praecox and epilepsy are much rarer." Both Birnbaum and Bonhöffer expressed surprise at the infrequency of manic-depressive conditions. Wollenberg found that the individuals who broke down during mobilization, and who had the least resistance, developed manic-depressive insanity, paranoid schizophrenias, episodic psychopathic excitements and occasional clouded states. The cases appearing at the front, on the other hand, were largely hysterias, anxiety states and exhaustive conditions. Birnbaum described psychoses similar to those reported by Awtokratow in the Russo-Japanese war and characterized by great weariness with a tendency to weeping, disturbed sleep and hallucinations related directly to unpleasant war experiences to which the patients had been subjected. He attributed these to exhaustion. Lust[100] quotes Mörchen as finding only five cases of war neuroses in forty thousand prisoners at Darmstadt and found very few cases in an additional twenty thousand which he investigated himself.
Westphal in 1915 expressed the opinion that there were neither war psychoses nor neuroses and that these conditions did not differ in any way from those described in times of peace. MacCurdy,[101] who made an elaborate study of war neuroses in 1917, described them as being either anxiety conditions or simple conversion hysterias. He looked upon fatigue as being a very important factor in the development of a neurosis, with either a physical accident or a mental shock as the precipitating cause. He defines war neuroses as "Those functional nervous conditions arising in soldiers which are immediately determined by modern warfare and have a symptomatology whose content is directly related to war." MacCurdy found that concussion could be considered as a possible factor in less than one-fourth of the cases he observed. He refers to minute cerebral and retinal hemorrhages with blood in the cerebrospinal fluid as an evidence that concussion is a cause in some cases. Curschmann, Meyers, Buzzard, Farrar and various others have noticed that the gross hysterical manifestations were extremely rare in officers. After an extended discussion of the etiology of the war neuroses, Farrar in 1918 expressed as one of his conclusions the opinion that "The drift of opinion is unmistakable towards the psychogenic basis of war neuroses of all types, including shell shock. Even in the initial unconsciousness or twilight state of some duration there is evidence that the psychogenic element may have as great if not a greater rôle than the item of mechanical shock, although this is also important."