To our knowledge, this is the first study of war-related disorders in German combatants of WWI employing current diagnostic criteria. The case files of the Psychiatric Department of the Charité are unique in that they offer a detailed account of psychopathological phenomena in German servicemen with post-combat disorders. Compared with Fraenkel  we had the benefit of the comparison with the international literature and modern diagnostic systems and incorporated cases from four, rather than one, years of the war.
Psychopathic constitution in the discussion of the time
The increase of admissions for functional disorders during the war years, which was not matched by an increase in classical psychiatric disorders—schizophrenia, manic-depressive illness and progressive paralysis—was already documented by Bonhoeffer . Whereas the pre-war admission criteria at the psychiatric unit of the Charité continued to apply during WWI , the proportion of male patients diagnosed with psychopathic constitution or hysteria increased dramatically from 12% in 1913 to 36% in 1915.
In our sample, only 20% of patients presented with primarily psychiatric symptoms, mainly depression and anxiety. Our data are in keeping with other studies (e.g. [45, 52]) which also found that servicemen with predominantly psychiatric presentation were relatively rare.
In our sample, the vast majority of servicemen with functional disorders (characterised by medically unexplained symptoms, comprising the ICD-10 categories of F44, F45 and F48) obtained a diagnosis of ‘psychopathic constitution’ (39 out of 85 patients, 46%) or ‘hysteria’ (42 out of 85 patients, 49%). This classification reflected the view of the Charité psychiatrists that individual predisposition, rather than the trauma of battle, was responsible for the development of symptoms and resulted in only 7 servicemen being granted compensation. This position was shared by the majority of contemporaneous psychiatrists and neurologists . A notable exception was Oppenheim, who had published a monograph on traumatic neuroses in 1889  and supported the view that hysteria could be triggered in anyone.
Psychogenic versus organic origin
The nature-nurture debate on the relevance of an individual’s underlying constitution was orthogonal to another contentious debate of the time, whether functional symptoms were psychogenic in origin or the result of objective pathological changes or lesions. Initially, the most prominent advocates of the organic case were Sarbo  and Oppenheim . However, Oppenheim later modified his view and claimed that not only physical trauma but also (psychological) shock could influence physical processes (through the ‘vasomotor-secretory-trophic nervous system’, which is strikingly similar to modern concepts of neuroendocrine stress responses). Two main arguments were made against organic causation. Firstly, if functional disorders were curable through hypnosis  or enforcement , then the underlying mechanisms had to be psychological rather than physiological. Secondly, hysterical disorders were not observed in prisoners of war (POW) camps , suggesting that symptoms arose only when soldiers were threatened with a return to hazardous combat ; yet both modern  and contemporaneous  research has shown that POWs, too, developed stress disorders.
A middle way was suggested by Moerchen , a medical officer at a POW camp in Darmstadt. He argued that psychological trauma or shock could cause subtle organic changes and trigger abnormal biological processes to the nervous system in the same way that psychological therapies (hypnosis, suggestion) could have a positive impact on organic disorders. It took over 80 years for these views to enter mainstream psychiatry . According to Moerchen, the cure or improvement of functional disorders through psychological therapies or the occasional spontaneous remission were compatible with an organic mechanism in the central or peripheral nervous system.
All functional disorders in the study were classified as ‘psychogenic’ in origin by the treating psychiatrists. This applied even to cases where functional symptoms were grafted on to objective organic pathology; for example, when a patient with a gunshot wound to the hand developed a progressive paralysis of that hand. Such grafting of functional symptoms on to organically affected limbs or organ systems was frequently observed by physicians of WWI . The one Berlin case of ‘traumatic neurosis’ also falls in this category because the symptoms were explained as consequences of a severe spinal injury which may explain why Bonhoeffer, who otherwise opposed Oppenheim’s theory, authorised the use of this term for this patient.
An intriguing observation of our study is the high proportion of psychogenic seizures (28% of cases) among German soldiers admitted to the Charité. To our knowledge, this phenomenon has not been reported in modern accounts of mental disorders resulting from combat trauma in WWI and WWII [24, 56]. With a few exceptions mentioned below, British military doctors paid little attention to psychogenic seizures and concentrated on functional disorders concerning the heart (Disorganised Action of the Heart: DAH [9, 41, 7, 31]) and sensory-motor system (pareses, tremor, speech disorders ). Conversely, German psychiatrists and neurologists reported high rates of seizure disorders [10, 16, 43], and conducted studies designed to differentiate between functional seizures/hysteria and genuine epilepsy. Both Goldstein  and Bonhoeffer  thought that the psychological impact of war could not cause genuine epilepsy in an individual without a constitutional predisposition. An opposing view was expressed by Richter , who recognised a genuine recurrent seizure disorder (‘Kriegsepilepsie’ or ‘war epilepsy’) that could be triggered by psychological trauma even in soldiers without predisposing factors. Richter, who based his article on his research in a specialised seizure unit within a military hospital between October 1917 and May 1918, distinguished between epileptic and more common hysterical seizures by means of the psychopathological criteria established by Hoche , for example the duration of seizures, pupillary reactions and state of consciousness.
In Britain, White  recorded ‘hystero-epileptic seizures with marked clonic spasms’ in young soldiers but neither he nor Hurst  provided any statistical data on which to base their incidence. Dudley Carmalt Jones , who was in charge of a specialist treatment centre for shell shock, opened in January 1917 at No. 4 Stationary Hospital, conducted a detailed clinical study of functional disorders of the war. He assessed 1300 patients admitted under the label ‘N.Y.D., N.’ (Not yet diagnosed, nervous) a few days after the onset of symptoms but only came across 3 cases of ‘violent hysterical fits’. Yealland , based at the National Hospital for Nervous Diseases, claimed that clonic-like fits were ‘the only type of hysterical seizure that occurred in soldiers in the recent war’ and that the classical arc de cercle of hysteria developed only in women and was exceedingly rare. Our records paint a different picture, with a wide range of pseudoseizures, including arc de cercle, in the soldier patients. It is currently not known whether this reflected a general difference in neurological manifestations of psychological trauma between Germany and Britain. An alternative explanation would be that certain types of manifestation were overrepresented in a secondary referral centre like the Charité. We intend to analyse records from other German and British hospitals to clarify this issue.
The changing face of post-traumatic syndromes
In the Berlin case records, we did not find evidence of post-traumatic syndromes as defined by the current diagnostic manuals. However, a small group of soldiers relived their traumatic combat experiences in dream-like dissociative states, mainly when waking up from a nightmare revolving around their war deployment. They showed aggressive outbursts with increased motor activity, re-staging of battle scenes (e.g. lying on the floor and shooting with an imaginary gun), unresponsiveness to external stimuli and amnesia for this episode afterwards. All received the contemporaneous diagnosis of ‘psychopathic constitution’ or ‘hysteria’. Under the heading of ‘Schreckpsychosen’, similar symptoms were described by Karl Kleist, then professor of psychiatry in Rostock, in 1918 . Following a shock or fright, Kleist’s cases of ‘anxious delirium’ (‘aengstliche Delirien’)—the most common form of ‘Schreckpsychosen’—, were in a dream-like state of consciousness, disoriented to time and place and reliving combat scenes under the influence of hallucinations. Afterwards typically hysterical symptoms became dominant again and there was amnesia for the episode. Kleist, who worked in a military hospital with a specialised psychiatric/neurological unit near the front line, also described dreams about horrifying war experiences, emotional hyperreagibility and hyperarousal as well as emotional blunting as effects of acute war trauma. These symptoms at least partly correspond to modern post-traumatic stress disorder (PTSD). Only few case records from Berlin (in addition to the 5 cases mentioned above) make a note of combat-related dreams or nightmares. More frequently, soldiers suffered from emotional blunting, detachment from other people, anhedonia and difficulties concentrating, but these symptoms lost out against the very dominant pseudoneurological and other functional symptoms. Very few soldiers had outbursts of anxiety or aggression, hypervigilance and hyperarousal. The relative rarity of this type of stress reaction and its differences from present-day PTSD support Jones’s theory that similar traumatic triggers can have different phenomenological consequences in different cultural settings .
We observed that dissociative disorders (F44.1/8/9 excluding dissociative disorders of movement and sensation F44.4/5/6) only occurred in servicemen who had been exposed to combat. These cases included the acute stress reaction described above which seems to overlap with Kleist’s ‘Schreckpsychosen’. According to Kleist, ‘Schreckpsychosen’ were the most common mental disorders on the theatre of war. Unlike war neuroses which commonly developed far away from the front line and persisted for a long time, they constituted acute and short-lived reactions to combat stress and were therefore rarely seen in military hospitals at home. Although most of our soldiers had long left the combat zone (most of them had been treated in several military hospitals before being referred to the Charité), some of them showed clinical pictures resembling Kleist’s Schreckpsychosen. All soldiers retrospectively diagnosed with dissociative symptoms (F44.1/8/9 excluding dissociative disorders of movement and sensation F44.4/5/6) and one case of ‘acute stress reaction’ (F43.0) strikingly resembled Kleist’s ‘Schreckpsychosen’. In our sample, however, we could not identify any cases with catatonic symptoms, which were also described by Kleist.
The term ‘Schreckpsychose’ is never mentioned in the Berlin case records. Bonhoeffer did not approve of this concept . Whereas Kleist believed that the shock alone was sufficient to cause symptoms as described above, Bonhoeffer saw the wish to be ill (and to escape combat) as the main factor contributing to the development and consolidation of symptoms.
In most of our cases, specific events were identified that had triggered the soldier’s mental breakdown (see Table 2). The documented triggers were both physical (for example, injuries obtained during front-line service or burial) and/or psychological (for example, conflict with superior). The influence of perceived intimidation or bullying by a superior was noted at the time . However, almost a quarter of the patients in our sample had not seen action and presumably never been exposed to any serious hazard. This phenomenon is of relevance to the ongoing debate whether genuine stress reactions require the experience of actual physical threat or whether its mere anticipation is sufficient. Whereas the PTSD definition requires exposure to a life-threatening event (criterion A, ), an anticipated or feared traumatic experience was sufficient to trigger a functional disorder. This phenomenon had also been observed in British servicemen awarded a war pension for a psychological disorder .
In most cases, symptoms started immediately after the trigger event. There were, however, a few cases of apparent latency between the perceived trigger and onset of symptoms of up to 5 months, which supports observations made by Schneider  and White . This phenomenon was to be replicated in the 1960 s with ‘delayed stress syndrome’ or ‘post-Vietnam syndrome’ and ultimately led to the formal recognition of PTSD in the DSM-III . Kurt Schneider explained the delayed symptom onset in terms of medical priorities. Close to the battlefield, physicians had to concentrate on life-threatening physical injuries while the treatment of neurotic symptoms had a lower priority so that they could develop almost undetected in the aftermath of combat. Schneider also claimed that hysterical symptoms were often masked by the application of certain medications such as hyoscine (scopolamine, an anticholinergic drug). Furthermore, he emphasised that compensation neurosis typically developed later, away from the battlefield, making it difficult for the individual to give up his symptoms. Schneider argued that neurotic soldiers should not be sent home away from their combat units because this would reduce their chances of returning to active duty. He suggested treating them with psychotherapy immediately after their traumatic experience. Schneider observed that soldiers who were not sent to distant treatment units often showed a spontaneous recovery from functional disorders. Ernst Jolowicz  who saw cases of functional disorders in treatment units close to the front line confirmed Schneider’s observation that neurotic symptoms consolidated in servicemen who had been evacuated from their combat unit. Because neurotic disorders appeared to have been relatively infrequent during the first few months of the war, a period of mobile warfare, he claimed that neurotic symptoms were characteristic of static trench warfare, a hypothesis that has been rephrased by modern psychiatrists  and historians [28, 56]. However, both our data and observations on the contagious nature of conversion disorders made at the time  show that exposure to trench warfare was not a requirement for the development of pseudoneurological syndromes. Jolowicz  also pleaded for early intervention near the battlefield to avoid pension claims, loss of manpower in combat units and unnecessary deterioration of health in the individual. At about the same time, Germany adopted the ‘forward psychiatry’ established by the British and French slightly earlier , by setting up dedicated treatment units close to the war zone .
Treatment strategies and differences in outcome
The prognosis of psychogenic seizure disorders was much worse than that of conversion disorders with sensory-motor symptoms. Commentators of the time noted that hysterical seizures and hysterical tremor were difficult to treat or treatment resistant [17, 34] whereas other functional disorders, such as hysterical deafness [3, 17], speech disorders and pareses , had a better prognosis even after long illness duration [5, 48].
The documented treatments at the Charité included eight cases of electrical stimulation of the affected body parts (with faradic brush), in two cases combined with suggestive methods, but none of the specific treatments proposed by Nonne  or Kaufmann . A speciality of the Charité psychiatrists seems to have been therapeutic admission to the locked ‘ward for the severely ill non-quiet cases’, which was reported to lead to immediate cure of functional symptoms in some cases. This type of behavioural intervention seems to have been rare elsewhere in the German system.
Fitness for duty
The low rate of return to full military duty reflected a general belief among German military psychiatrists that individuals with psychopathic constitution were not suitable for front-line service [2, 6, 48, 44]. This was in contrast to the later practice in WWII, where the remit of psychiatric practice was to make traumatised soldiers fit for return to active duty .
Although the British came to similar conclusions [17, 52], their practice of returning soldiers with functional disorders to active duty seems to have been different. Jones  who carried out a study on 1,300 admissions to a specialist shell shock unit in a stationary hospital doubted that ‘anyone who has once developed it (shell shock) will ever be fit for front-line soldiering within the time limit of any war’. Despite this view, about 40% of his patients without complicating organic pathology were reportedly returned to active service, about 40% to light duty or prolonged rest previous to duty and about 20% to base hospitals. He justified this course of action with the high demand for men in the combatant units: ‘it has been the duty of medical officers to risk error rather in the direction of sending up possibly unfit men than in that of losing possibly fit men to their units’. With a larger standing army, the German command might have been more tolerant of medical discharge than the British. However, retrospective study of Carmalt Jones’s data has shown that his published return to duty rate was exaggerated and the actual proportion of admissions that immediately returned to active duty was only 17% . Yet, because of the pervasive belief in the importance of the ‘psychopathic constitution’, unfitness for duty did by no means lead to a successful compensation claim.