There is little doubt that the term dissociation had its origin in Pierre Janet, or more precisely, in his idea of désagrégation, at a very specific time and place in history, the French fin-de-siècle. Sigmund Freud also deserves a mention, because it is around this time when references to the concept of dissociation start appearing in his work. He will soon drop the idea in favor of repression, and his theories will move in a new direction, leaving hypnosis behind and embracing the new ideas of psychoanalysis. Both authors had conflicting views regarding the origin of dissociation, but their studies overlapped at different points, often leading to the same conclusions [6].

Different concepts start appearing in the works of Pierre Janet (suggestion, subconscious, narrowing of the field of consciousness, psychological misery, fixed ideas) that will lay the foundations and blaze the trail for his désagrégation psychologique. His greatest work is L’Automatisme Psychologique (1889), the result of the research he carried out in the lab of El Havre hospital, in which he expounds his theory of disaggregation [4].

It was thanks to his clinical observations of patients, and partial catalepsies, that Janet came up with the idea of partial consciousness, the dissociation of the content of consciousness in different compartments. He described women who performed actions subconsciously, that is to say “actions that had all the features of a psychological fact except one, which is that the subject is unaware of what he is doing in the moment he is doing it” [4]. Psychological automatism does not direct all conscious thinking but only a small group of phenomena partially separated from the overall consciousness of the individual that continue to act of their own accord and in a different manner. These partial automatisms have as their simplest form of expression partial catalepsies and suggestions by means of distraction.

For Janet ideas develop into acts. It is no coincidence that his psychological automatism should have carried the subtitle “Experimental-psychological essay on the inferior forms of human activity” [4]. Distraction, according to this author, seems to split the field of consciousness into two parts: one that remains conscious, and another that the subject seems to be unaware of. The distraction would be equivalent to an anesthesia, by means of which we can suggest acts, but also hallucinations. While the distracted consciousness is occupied with other ideas, the suggested act is performed without the subject knowing about it.

By means of suggestion Janet discovers that he can suppress certain sensations, producing in the subject partial blindness or deafness. A suggestion of a negative hallucination or systematic anesthesia was used. The first term came from Bernheim (1886) and the second from and Binet and Fére, the latter seeming more accurate to Janet, since he viewed the phenomenon as being analogous to the systematic paralysis of movement [10].

Janet’s understanding is that during conscious perception of sensations, there is an operation in two stages. First, there is a confluence of all of the sensations coming from the different senses and then there is an active synthesis of these sensations as they cluster together, and aggregate themselves to a given perception. It so happens that in the “distracted hysterical” [4] subject there are a set of sensations that during the second operation escape from consciousness. They cannot be linked to the personality of the subject, and therefore, the self is not aware of them. Synthesis is weak and restricted.

Janet considers “systematic or even general anesthesia an injury, a weakening, not of sensation, but of the ability to synthesize sensations, rendering a personal perception, all of which implies a true disaggregation of psychological phenomena” [4].

We can see that this initial concept of dissociation, Pierre Janet’s psychological disaggregation, is a concept that stems from the analysis of somatic phenomena, partial catalepsis, and systematic anesthesia, and that it describes “the dissociated body” [4] of sick people, generally hysterical women. Even in the prologue to his philosophy thesis, Psychological Automatism, he cites the names of four women, Léonie, Lucie, Rose, and Marie, who were the women that Janet considered as having “the conditions of a good psychological experience” [4]. Later, in 1898, Janet [11] published Néuroses et Idées Fixes, in which he gathered all of the articles he published between 1891 and 1897 on the subject of different psychopathological disorders and their therapy, and which were the result of his work in the ward of Charcot in La Salpêtrière, treating hysterical patients, among them were Madame D., Isabelle, Marcelle, Justine, Madame A., etc. One of the few references to male patients is the case of Achilles, who suffered from manifestations of demonic possession.

“It is undeniable that what gave hysteria coherence over a long period of time was its exclusively female nature” [12].

Up until the twentieth century three possible origins for hysteria were considered, the uterus, the brain, and the nerves. The first option justified that only women should suffer from the condition, but later on its origin was generally thought to be located in the brain, and, owing to the analogy between crises of hysteria and epileptic convulsions, it was determined that there had to be only one organ involved in the pathology. This is how the concept of hystero-epilepsy came into existence, consecrated by the Charcot school.

In this fin-de-siècle Paris, hysteria continued to be a condition exclusively related to women. Records detailing manifestations of hysteria were always connected with female patients. It was Charcot himself, however, who demonstrated that hysteria was also a male affliction. One of his students, Professor Pierre Maire said to his teacher: “The most salient feature of Charcot’s work on the subject of hysteria, the main formulation that will not be lost and that will serve as a guideline to future generations of doctors, is his demonstration that male hysteria exists” [13].

We cannot forget the historical context in which this shift to male hysteria took place. The most important phenomenon in the industrial world of the nineteenth century was the railway, which can be considered, in the words of Hacking “the epic symbol of the psychologizing of trauma” [14]. The railway gave the very idea of accident its modern meaning, that is, among other things, that something can happen randomly or without apparent cause. The term railway spine appears, coined by Johen Eric Erichsen, to refer to those symptoms that did not match any recognizable physical injury. Three years later Russel Reynolds [14] tries to demonstrate that certain disorders such as paralysis, spasms or other alterations of the sensations may depend on the morbid state of a sole idea, or an idea together with an emotion, and such a formulation cannot elude being compared to hysteria. This syndrome was a chance for Charcot to render hysteria potentially male. Gynecologists and obstetricians claimed this territory as their domain; thus, the best way to take the disease away from the gynecologists was to declare that it belonged to both sexes. Up to then male hysteria was recognized, but within the context of an “effeminate” [14] personality. Charcot [15] in his lessons on the disease of the nervous system (1887) discussed the symptoms that Russel Reynolds had described, provoking, by means of hypnosis, the symptoms in a male subject whose masculinity was beyond question. Thus, “memory, hysteria, hypnosis and physical trauma were closely linked together in the lectures by Charcot” [14].

After having worked for 6 or 7 years in El Havre, Janet [16] arrived at La Salpêtrière and followed the teachings of his master Charcot, which ended with his thesis in medicine L’État Mental des Hystériques, in which he outlined and completed his studies on the subject of hysteria. According to López Piñero and Morales Meseguer [17], the historical foundations of Janet’s initial thinking could be traced back to his being a student first of Ribot and then of Charcot. And it is precisely Charcot’s contributions on fixed ideas that were core to certain neuroses and that formed the starting point of Janet’s theory of dissociation. In his work L’État Mental des Hystériques the author explains the existence of purely somatic phenomenology whose etiology is psychological and Charcot is the first one to link these physical symptoms with traumatic phenomena. According to Janet, hysteria is a mental illness in which there is cerebral stress and also very vague physical symptoms. There is a weakening of the field of consciousness that prevents certain sensations and images from being perceived, and they remain beyond the scope of personal perception. This lack of synthesis enables parasite ideas to form, and since these are completely isolated from the control of personal consciousness, they manifest themselves as disorders in physical appearance. These parasite ideas are the germ of Janet’s fixed ideas, which are the cause of mental accidents in hysterics and were how Charcot explained traumatic hysteria.

Well, gentlemen: thanks to recent findings in the science of hypnotic neurosis, we have been able to intervene to a certain extent, and advance experimentation in the study of cases of this nature. We know that, in individuals in a state of deep hypnosis, it is possible to give birth to, by means of suggestion and intimidation, an idea, a coherent group of associated ideas, which settles in the mind in a similar way to a parasite, becoming isolated from everything else, and which can translate externally in corresponding motor skill phenomena [15].

Charcot devotes himself to the study of hysteria, which affects not only women, but also men and children. It is a disease with multiple symptoms such as contractions, paralysis, anesthesia, convulsions, hallucinations or delirium. From 1878 onwards he becomes interested in hypnosis, a method by which he can provoke in his patients the symptoms of hysteria, and he defends hypnosis and hysteria only being possible in people with weak and degenerate nervous systems.

Charcot is criticized by Liébeault and Bernheim, who deny that there is a link between hypnosis and hysteria and defend that the prerequisite that is necessary for hypnosis to be performed is suggestibility and not the mental disease. After this attack, Charcot begins his work on the psychologizing of hysteria, and, without forgetting its neurological grounding, he proposes a psychological explanation, admitting that personality disorders caused by traumas are a triggering factor in hysteria. This approach permits a therapy to be developed, and such a therapy would be devised by two of his disciples, Freud and Janet [18].

At the end of the nineteenth century and beginning of the twentieth century, the role played by emotion in the triggering of hysteria became controversial. According to Janet past traumatic events that “were forgotten” remained active at the subconscious level, forming fixed ideas, endowed with a life of their own in a dissociated consciousness. From Janet’s point of view emotion produced a state of dissociation, narrowed the field of consciousness, and enabled the fixed idea to settle. From Freud’s point of view, however, emotion, because of its charge of excitation, submits the body to an overcharge that it is not able to get rid of through the normal channels of abreaction (release of emotional tension).

In the preliminary Communication of 1893, Freud and Breuer extend to all hysteria the pathogenic formula proposed by Charcot for hystero-traumatic paralysis.

Freud describes in this work two psychological operations in the process of traumatic neuroses [19]. One is a mechanism of dissociation, by which there is a rupture in the association between a function of the body and the rest of its psychological activity. The second is a clivage (Spaltung), which would keep this separation or diversion completely apart, to the point when it becomes unbridgeable, leaving all these dissociated phenomena inaccessible to any form of association. In order for these mechanisms to kick in, there must be a charge of intense affective value. The difference between Janet’s and Freud’s understanding regarding this dissociation is that the former explains it as a result of a deficit in the synthesis function or a narrowing of the field of consciousness, while the latter links it to the affective charge.