Neurophysiologie Clinique/Clinical Neurophysiology (2014) 44, 411—416
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Conversive disorders among children and adolescents: Towards new ‘‘complementarist’’ paradigms? Troubles conversifs de l’enfant et de l’adolescent : vers de nouveaux paradigmes complémentaristes ? L. Ouss ∗, E. Tordjman Necker hospital, 149, rue de Sèvres, 75015 Paris, France Received 22 January 2014; accepted 27 July 2014 Available online 6 September 2014
KEYWORDS Conversion disorder; Child; Adolescence; Psychoanalysis; Neuroscience; Complementarism; Attachment
∗
Summary This paper aims to describe current questions concerning conversive disorders among children and adolescents. We first describe prevalence and clinical characteristics of these. Many unresolved questions remain. Why do patients show excess, or loss of function? Attachment theory offers a relevant framework to answer this question. Does neurobiology of conversion disorders shed light on conversive processes? Current neurobiological research paradigms focus on the symptom, trying to infer processes, instead of proposing paradigms that test theoretical hypotheses. The most convincing theoretical framework that has already proposed a coherent theory of conversion is a psychodynamic one, which has not yet been tested with neurobiological paradigms. The interest of studying child and adolescent conversive disorders is to provide a means to more deeply investigate the two challenges we face: theoretical, and clinical ones. It provides the opportunity to access a pathopsychological process at its roots, not yet hidden by many defensive, rationalizing attitudes, and to better explore environmental features. We propose a ‘‘complementarist’’ model, which allows the combination of different approaches (neural, cognitive, environmental, attachment, intra-psychic) and permits proposal of different levels of therapeutic targets and means. © 2014 Elsevier Masson SAS. All rights reserved.
Corresponding author. Tel.: +33 6 61 90 99 46. E-mail addresses: [email protected] (L. Ouss), [email protected] (E. Tordjman).
http://dx.doi.org/10.1016/j.neucli.2014.07.004 0987-7053/© 2014 Elsevier Masson SAS. All rights reserved.
412
MOTS CLÉS Troubles conversif ; Enfant ; Adolescent ; Psychanalyse ; Neurosciences ; Complémentarisme ; Attachement
L. Ouss, E. Tordjman Résumé Cet article propose une revue des questions actuelles concernant les troubles conversifs de l’enfant et de l’adolescent. Il en décrit la prevalence, les caractéristiques cliniques. Mais il reste des questions non résolues. Pourquoi les patients ont-ils tantôt une perte, tantôt un excès d’une fonction ? La théorie de l’attachement propose un cadre pertinent pour répondre à cette question. Les données neurobiologiques actuelles sur la conversion éclairent-elles les processus conversifs ? Les paradigmes neurobiologiques actuels se concentrent sur le symptôme, essaient d’en inférer des processus, plus qu’ils ne proposent des paradigmes qui testent des hypothèses théoriques. De fait, le cadre théorique le plus pertinent jusqu’ici pour comprendre les troubles conversifs est psychodynamique ; il n’a pas encore été testé avec des paradigmes neurobiologiques. L’intérêt d’étudier les troubles conversifs de l’enfant et de l’adolescent est d’aider à répondre aux deux challenges restants : théorique, et clinique, en permettant d’avoir accès au processus, à ses origines, avant qu’il ne soit remanié par des défenses ou des attitudes rationnalisantes, et de mieux explorer les caractéristiques environnementales. Nous proposons un modèle « complémentariste », qui permet de combiner différentes approaches (neurale, cognitive, environnementale, attachementiste, intrapsychique), et de proposer différents niveaux de cibles et moyens thérapeutiques. © 2014 Elsevier Masson SAS. Tous droits réservés.
Lasègue (1816—1883) wrote: ‘‘Hysteria has never been defined, and never will be’’ [26]. This sentence remains true for conversive disorders, a term which has supplanted that of hysteria. The DSM-V and ICD-10 classifications differ in describing conversive disorders [1,46]. This disorder is often confused with somatization disorder. Diagnoses of exclusion are more frequent than positive ones. It is therefore difficult to accurately characterize conversive disorders, especially among children and adolescents, mainly because the prevalence is lower than in adult cases, and referrals come from various sources (general practitioners, pediatricians, psychiatrists, child neurologists, orthopedic surgeons, and so on). Finally, this diagnosis is often accompanied by medical counter attitudes, variously named and badly accepted by the patients [41]: hysteria and conversion are stigmatizing diagnoses. It is a great challenge to try to characterize conversive disorders among children and adolescents, because this allows access to the roots of a pathopsychological process, not yet hidden by many defensive, rationalizing attitudes. Family involvement and environmental features are easier to explore, since family is involved, and this can help in understanding such a process.
Characteristics of conversive disorders among children and adolescents
other groups of somatoform disorders (2.1:1 ratio in somatoform disorders, [13]). For some authors, sex-ratio depends on the age: 57% girls before 10 years, versus 76% in a 10—16 years sample [19], though not for others, reporting 75% female in both groups, under 10 years and 10—15 years old [2]. Sex-ratio also depends on the symptoms, although this feature is somewhat controversial since more boys 5—10 years and more girls after 12 years are reported to have psychogenic non-epileptic seizures (PNES) [16]. The prevalence seems to have changed across time: from 15.8% boys between 1987 to 1996, to 52.2% from 1997 to 2006, probably due to increasing extrafamilial stress [14].
Age Symptom onset is reported in most studies to occur around 12 years (median age 12.5 years, [2]), but this seems to depend on the type of symptoms. It appears earlier in PNES (8.2 years for boys, 9.4 years for girls, [3]). Conversive disorder rarely appears before 8 years. It takes 11.6 months between the first episode and the diagnosis [2,35], more in the case of PNES (1.3 years, [16]).
Symptomatology Prevalence The prevalence is hard to determine: studies cite from 2.3 to 4.2/100,000 in pediatric clinics [19]; 0.2% to 2% of children in child psychiatry out-patient clinics [11,13,27,28]; and 0.78% of inpatients for somatoform disorders with 57.3% of conversion disorders [13]. Some authors have described cultural differences in prevalence (14.8% in an Indian sample [40]).
Sex-ratio Girls are more represented among conversion disorder patients, and represent a higher proportion compared to
The most frequent symptoms are PNES (52.1% fainting attacks [or ‘‘pseudosyncope’’]) [9] and pseudoseizures (21.1% [13]; 40% [2]; 84% [35]), and motor symptoms (64% [5], motor weakness 63.3% and abnormal movements 43.2%, [2]). Sensory symptoms are less prevalent: 7.5% [35] to 24% [19]. Pain is associated in 34 to 68%. Usually, more than 2 symptoms appear (57% [32]; 20% [24]; 55% [19]). A ‘‘borrowing’’ symptom exists in 29 to 54% cases, in which the physical symptoms appears to be copied from a family member [12,24,29]. The classical sign of ‘‘belle indifference’’ is discussed (46.7% [9]; 27.1% [2]), but seems to be non-pathognomonic in adults [42].
Conversive disorders among children and adolescents
Familial factors Familial factors are frequent; studies find often two types of families [12,19]. The first type is the chaotic family, with somatic and psychopathological symptoms among family members, and the second, the family without social or psychopathological difficulties, with high cognitive level, high academic expectations and anxiety about disease and death. Among family members, 26% are diagnosed with psychiatric disorders (depressive and anxiety disorders), and 23% with medical conditions, in the year preceding onset of conversion disorder; a family history of conversion disorder was found in 3%[2]. Boys have higher rates of poor interpersonal relations and communication problems within the family, and girls have higher rates of conflicts with the parents and other family members; sibling rivalry is found in 23.4% [2].
Stress factors Stress factors are diversely found [2,12,13,19,36], in 10% [12] to 90% [2,35]: school stress (12.5% to 58% [13,19,24] including bullying or victimization in school, 23.8% [2]), relational stress (52.5% [35]), medical diseases in relatives (25% [35]), parental separation 19% [2] and death of a relative or friend 16.7% [2]. Among 73.4% of cases with identifiable stressors in somatoform disorders, 14.5% had acute precipitating stressors, with an even higher proportion in conversion disorder [2]. What is remarkable and less known is that less abuse is found in children than in adults (4% [19], 6.6% [2], to 32% in PNES [47]). However, none of the authors considers puberty as an internal stress factor, except Bertrand Cramer in his remarkable clinical paper [1977,5].
Comorbidities Comorbidities are the usual ones found also in adult cases: 45% [35], more frequent anxiety disorders than depressive disorder (37.2% versus 15.7% [36], 18.2% versus 8.8% [2]), with psychotropic medication (55% [35], 14% [19]). Ani et al. found no mental disorder prior to the episode in 78% [2].
Favorable prognosis Some factors are associated with favorable prognosis: young age, sensory rather than motor symptoms, acuteness of presentation, onset precipitated by a stressful event, good premorbid health, good socio-economic status, absence of any other concomitant organic disease or major psychiatric symptoms — especially depression, absence of personality disorder [3,24,35,43,47]. Ani et al. found a new psychiatric disorder during the one-year follow-up period in 28% (anxiety disorder 14%, depressive disorder 13%, school phobia 9%) [2].
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Unresolved questions concerning conversive disorders Many questions remain concerning the process of conversive disorders.
Functional loss, or excess? What determines the nature of the symptom? Some patients show a lack of function (such as paralysis or sensory impairment), and other show positive symptoms (pain, abnormal movements, PNES, etc.). Some suggestions have been made to explain this. The symptom could be determined by a previous organic symptom (such as tendinitis or fracture), or could be ‘‘borrowed’’ from a relative, what Freud and Breuer (1895) called ‘‘somatic compliance’’ [25]. This idea can also be linked to Damasio’s theory of somatic markers (1994, [7]). Somatic markers are associations between reinforcing stimuli, somatic experiences that induce an associated physiologic affective state, which bias the way in which a further similar experience will be interpreted and thus the decision of how to act. Kozlowska has put forward one of the most interesting proposals [18,21]: that conversive symptoms during childhood or adolescence could be a sensori-motor component of two different ethological organizations. She refers to Kretschmer [23] and Nijenhuis et al. [33], these authors having already proposed that negative symptoms in conversion disorders could be seen as components of the animal ‘freezing response’. However, Kozlowska also refers to Morris et al. [31], who propose that ‘‘conversion positive symptoms could be related to a different type of animal behaviour called ‘behavioural deception’ or ‘deceptive signaling’, a behaviour that conveys ‘false’ information to a receiver, like an exaggerated behavioural display, to attract attention and to confuse the predator by the use of false signals’’ [18]. Kozlowska [21] proposes to extend this ethological point of view in the perspective of human development, referring to Crittenden’s dynamic-maturational model of attachment, a theory about protecting oneself from danger [6]. This model analyses development through ‘the interactive effects of genetic inheritance, maturational processes and person-specific experiences to produce individual differences in strategies for keeping oneself safe’ ([6], p. 105). They distinguish two types of defensive strategies against fear in animals: type A, being an inhibitory, immobilization or ‘‘freezing response’’; the second type, B, consisting of activatory, diversion ‘‘appeasement defense behavior’’. In a convincing way, Kozlowska [22] showed two distinct subtypes of conversion patients: those using psychological inhibition and those using psychological coercionpreoccupation, whose symptoms fell into discrete clusters. In this way, the nature of the conversive symptoms can be understood in the framework of an ethological/attachment system.
Does the neurobiology of conversion disorders shed light on conversive processes? In this special journal issue, Vuilleumier and Voon describe the current state of neural mechanism findings concerning
414 adult conversive disorders. The aim of this paper is not to discuss these results (see Vuilleumier in this issue for this review), but simply to make some comments. It remains difficult to reach a final conclusion, for many reasons. There are still few studies in this field, and they concern very few patients (although numbers included are tending to increase; maximum 16 patients, [45]). The paradigms proposed are rather sophisticated [4,44] and studies tend to focus, except Voon et al. [45], on negative symptoms. We probably face the first step of brain exploration of conversive disorders, because the research focuses on the manifest symptom (motor, sensory), but not on the underlying process. These studies shed light more on neural correlations during conversive disorders, than on the symptom production processes. Since conversive disorders lack a relevant theoretical framework, we do not have research paradigms that are relevant in terms of underlying pathopsychological processes. Why do most researchers focus on the symptom, grouping together patients only with similar symptoms, despite the fact that we include in the same conversion diagnosis patients with different symptoms? Why do they focus on the symptomatic result of the disease, instead of building paradigms relevant to etiological hypotheses? The most convincing theoretical framework that has already proposed a coherent theory of conversion is a psychodynamic one (Freud, Breuer 1895, [9]): that conversion could be produced by a repression mechanism of unbearable representations, converting these into somatic features. Researchers are familiar with cognitive paradigms: one hypothesis, one paradigm, one task that tests it. Are psychoanalysts ready to work with neuroscientists, and the most important: are neuroscientists ready to test psychodynamic hypotheses? Some have already constructed neurophysiological or MRI paradigms that test repression, referring to primary/secondary processes [39] or to Jung [15,38], who proposed that the level of physiological arousal during free association indicates whether contents are related to repressed conflicts. We propose in Table 1 a correspondence between theoretical psychodynamic frameworks and hypotheses, and paradigms that should be tested.
What are the challenges? The interest of child and adolescent conversive disorders At least 2 kinds of challenges remain: theoretical and clinical. The technical challenges (paradigms, MRI, etc.) are no longer a problem when the right questions are asked. The main challenge is to redefine our theoretical frameworks. Without any coherent theory, we cannot build coherent paradigms. The study of child and adolescents conversive disorders can help us to go deeper into the theory, for many reasons: • it allows evaluation of the ‘‘real’’ psychopathological process at its roots, not yet hidden by many defensive and rationalizating attitudes; • most of the conversive roots are anchored in early child and adolescent experience, and processes, such as
L. Ouss, E. Tordjman Table 1 Correspondence between theoretical psychodynamical frames, hypotheses and paradigms. Theory (Freud/Breuer, 1895 [9])
Paradigm proposition
Somatic compliance/embodied memories
Somatic markers, procedural memory, encoding paradigms Trauma paradigms (episodic memory) Episodic memory with emotional and sexual stimuli: retrieval paradigms Resting state that assesses default mode network; connectivity analysis [10,30] Attentional paradigms
Traumatic experience ‘‘Hysterics suffer from reminiscences’’
Variations in ‘‘intracerebral tonic excitation’’ (Breuer, in 1895 [9]) Attentional bias, (Breuer, in 1895 [9]) Symbolisation in conversion versus no symbolisation Repression
Primary/secondary processes paradigms Repression paradigm
attachment behavior and representations, which are difficult to explore many years later; • environmental features are easier to explore, when family is involved and can help to understand such a process. No neurophysiological studies have been yet carried out on children and adolescents, for ethical reasons, and for practical ones (less patients, shorter period of symptoms, better prognosis, dental braces, etc.). We have to better characterize the clinical presentation of conversive patients, according to the nature of the symptom (for example, positive or negative; motor, sensory, cognitive, etc.). We must also evaluate comorbidities; cognitive functioning [20]; psychic organization; and attachment style. We should study what is common to different conversion disorders in terms of profiles or processes, rather than what is common to symptoms. The symptom is only the final expression of a complex process.
A synthesis? A complementarist approach Fig. 1 represents a proposition of the whole complex process of conversive disorder. Kozlowska [17] has begun to describe this and we integrate some of the stages she proposes. However, she never refers to psychodynamic theory, or to repression, which probably remains a core process. Afferent information coming from sensory pathways, triggered by external or internal stimuli, are stored as ‘‘body states’’, which are processed and represented within the cognitive system [20] and underlying neural substrate [17]. These body states depend also on preceding early experiences, above all those that are traumatic or not yet transformed. In some conditions, depending on attachment style, or triggering events (internal events like puberty, or external emotional events, which sometimes refer to early traumatic or unelaborated experience), these
Conversive disorders among children and adolescents
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Figure 1 The whole process of conversion symptom production [in blue, the neural and cognitive levels. In purple, environmental level. In green, attachment level. In orange, symptomatic level. Blue rectangles signal processes. Red stars signal therapeutical levels].
dormant representations bias cognitive and neural processing of new information [17]. These representations are sometimes repressed; when unbearable, the early experience is sometimes directly re-enacted as bodily symptoms. New information is re-interpreted as the subjective experience of an involuntary symptom, and sometimes re-expressed similarly to the previous event, in an analogous way; for example, previous experience of motor loss in a limb, that is subsequently behaviorally expressed as motor, sensory or cognitive symptoms. We could then propose a different focus of therapy: memory and trauma integration to elaborate the traumatic process; trans-magnetic stimulation (TMS) to directly reach the neural system (despite the fact that there is insufficient good quality evidence to establish TMS as an effective treatment modality [37]); attachment therapy that can influence the behavioral expression; family guidance to elaborate the environmental features; psychodynamic psychotherapy for repression; and physiotherapy to directly treat the symptom. The principal interest of this model is to propose a complementarist approach in order to combine different levels (neural, cognitive, environmental, attachment, intrapsychic) [34]. ‘‘Complementarism’’ (Devereux, in 1972 [8]) was first used in an ethno-psychiatric framework. Devereux describes a position that necessarily takes into account two theoretical frames, but not simultaneously. Successive shifts allows us to take one position, and then another. This is not a choice; it is a necessary position, an inevitable methodology that allows one to study the same object from two different points of view without equating one to the other. This approach also allows differentiation of different kinds of therapeutic targets and means. We propose an
‘‘and-and’’, rather than an ‘‘or-or’’ epistemology: we have to take into account both the neurophysiological and the intra-psychic levels, to understand the process of symptom production. Most authors propose the promotion of a multidisciplinary collaboration between pediatricians, psychologists and psychiatrists. We go further in arguing that each level corresponds to a therapeutic proposition. We might thus question whether we should try to cure defensive symptoms or not: it is often necessary to respect the symptom, until we understand its role. Such respect however does not mean that we do not attempt to cure it. On the other hand, we have to remain aware that if the symptom has any role in the psyche, its rapid disappearance without any psychic elaboration will certainly be followed by the reappearance of another symptom. In conclusion, clinicians and neurophysiologists have to work together to try, if possible, to deepen their understanding of conversive patients.
Disclosure of interest The authors declare that they have no conflicts of interest concerning this article.
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REVIEW/MISE AU POINT
Conversive disorders among children and adolescents: Towards new ‘‘complementarist’’ paradigms? Troubles conversifs de l’enfant et de l’adolescent : vers de nouveaux paradigmes complémentaristes ? L. Ouss ∗, E. Tordjman Necker hospital, 149, rue de Sèvres, 75015 Paris, France Received 22 January 2014; accepted 27 July 2014 Available online 6 September 2014
KEYWORDS Conversion disorder; Child; Adolescence; Psychoanalysis; Neuroscience; Complementarism; Attachment
∗
Summary This paper aims to describe current questions concerning conversive disorders among children and adolescents. We first describe prevalence and clinical characteristics of these. Many unresolved questions remain. Why do patients show excess, or loss of function? Attachment theory offers a relevant framework to answer this question. Does neurobiology of conversion disorders shed light on conversive processes? Current neurobiological research paradigms focus on the symptom, trying to infer processes, instead of proposing paradigms that test theoretical hypotheses. The most convincing theoretical framework that has already proposed a coherent theory of conversion is a psychodynamic one, which has not yet been tested with neurobiological paradigms. The interest of studying child and adolescent conversive disorders is to provide a means to more deeply investigate the two challenges we face: theoretical, and clinical ones. It provides the opportunity to access a pathopsychological process at its roots, not yet hidden by many defensive, rationalizing attitudes, and to better explore environmental features. We propose a ‘‘complementarist’’ model, which allows the combination of different approaches (neural, cognitive, environmental, attachment, intra-psychic) and permits proposal of different levels of therapeutic targets and means. © 2014 Elsevier Masson SAS. All rights reserved.
Corresponding author. Tel.: +33 6 61 90 99 46. E-mail addresses: [email protected] (L. Ouss), [email protected] (E. Tordjman).
http://dx.doi.org/10.1016/j.neucli.2014.07.004 0987-7053/© 2014 Elsevier Masson SAS. All rights reserved.
412
MOTS CLÉS Troubles conversif ; Enfant ; Adolescent ; Psychanalyse ; Neurosciences ; Complémentarisme ; Attachement
L. Ouss, E. Tordjman Résumé Cet article propose une revue des questions actuelles concernant les troubles conversifs de l’enfant et de l’adolescent. Il en décrit la prevalence, les caractéristiques cliniques. Mais il reste des questions non résolues. Pourquoi les patients ont-ils tantôt une perte, tantôt un excès d’une fonction ? La théorie de l’attachement propose un cadre pertinent pour répondre à cette question. Les données neurobiologiques actuelles sur la conversion éclairent-elles les processus conversifs ? Les paradigmes neurobiologiques actuels se concentrent sur le symptôme, essaient d’en inférer des processus, plus qu’ils ne proposent des paradigmes qui testent des hypothèses théoriques. De fait, le cadre théorique le plus pertinent jusqu’ici pour comprendre les troubles conversifs est psychodynamique ; il n’a pas encore été testé avec des paradigmes neurobiologiques. L’intérêt d’étudier les troubles conversifs de l’enfant et de l’adolescent est d’aider à répondre aux deux challenges restants : théorique, et clinique, en permettant d’avoir accès au processus, à ses origines, avant qu’il ne soit remanié par des défenses ou des attitudes rationnalisantes, et de mieux explorer les caractéristiques environnementales. Nous proposons un modèle « complémentariste », qui permet de combiner différentes approaches (neurale, cognitive, environnementale, attachementiste, intrapsychique), et de proposer différents niveaux de cibles et moyens thérapeutiques. © 2014 Elsevier Masson SAS. Tous droits réservés.
Lasègue (1816—1883) wrote: ‘‘Hysteria has never been defined, and never will be’’ [26]. This sentence remains true for conversive disorders, a term which has supplanted that of hysteria. The DSM-V and ICD-10 classifications differ in describing conversive disorders [1,46]. This disorder is often confused with somatization disorder. Diagnoses of exclusion are more frequent than positive ones. It is therefore difficult to accurately characterize conversive disorders, especially among children and adolescents, mainly because the prevalence is lower than in adult cases, and referrals come from various sources (general practitioners, pediatricians, psychiatrists, child neurologists, orthopedic surgeons, and so on). Finally, this diagnosis is often accompanied by medical counter attitudes, variously named and badly accepted by the patients [41]: hysteria and conversion are stigmatizing diagnoses. It is a great challenge to try to characterize conversive disorders among children and adolescents, because this allows access to the roots of a pathopsychological process, not yet hidden by many defensive, rationalizing attitudes. Family involvement and environmental features are easier to explore, since family is involved, and this can help in understanding such a process.
Characteristics of conversive disorders among children and adolescents
other groups of somatoform disorders (2.1:1 ratio in somatoform disorders, [13]). For some authors, sex-ratio depends on the age: 57% girls before 10 years, versus 76% in a 10—16 years sample [19], though not for others, reporting 75% female in both groups, under 10 years and 10—15 years old [2]. Sex-ratio also depends on the symptoms, although this feature is somewhat controversial since more boys 5—10 years and more girls after 12 years are reported to have psychogenic non-epileptic seizures (PNES) [16]. The prevalence seems to have changed across time: from 15.8% boys between 1987 to 1996, to 52.2% from 1997 to 2006, probably due to increasing extrafamilial stress [14].
Age Symptom onset is reported in most studies to occur around 12 years (median age 12.5 years, [2]), but this seems to depend on the type of symptoms. It appears earlier in PNES (8.2 years for boys, 9.4 years for girls, [3]). Conversive disorder rarely appears before 8 years. It takes 11.6 months between the first episode and the diagnosis [2,35], more in the case of PNES (1.3 years, [16]).
Symptomatology Prevalence The prevalence is hard to determine: studies cite from 2.3 to 4.2/100,000 in pediatric clinics [19]; 0.2% to 2% of children in child psychiatry out-patient clinics [11,13,27,28]; and 0.78% of inpatients for somatoform disorders with 57.3% of conversion disorders [13]. Some authors have described cultural differences in prevalence (14.8% in an Indian sample [40]).
Sex-ratio Girls are more represented among conversion disorder patients, and represent a higher proportion compared to
The most frequent symptoms are PNES (52.1% fainting attacks [or ‘‘pseudosyncope’’]) [9] and pseudoseizures (21.1% [13]; 40% [2]; 84% [35]), and motor symptoms (64% [5], motor weakness 63.3% and abnormal movements 43.2%, [2]). Sensory symptoms are less prevalent: 7.5% [35] to 24% [19]. Pain is associated in 34 to 68%. Usually, more than 2 symptoms appear (57% [32]; 20% [24]; 55% [19]). A ‘‘borrowing’’ symptom exists in 29 to 54% cases, in which the physical symptoms appears to be copied from a family member [12,24,29]. The classical sign of ‘‘belle indifference’’ is discussed (46.7% [9]; 27.1% [2]), but seems to be non-pathognomonic in adults [42].
Conversive disorders among children and adolescents
Familial factors Familial factors are frequent; studies find often two types of families [12,19]. The first type is the chaotic family, with somatic and psychopathological symptoms among family members, and the second, the family without social or psychopathological difficulties, with high cognitive level, high academic expectations and anxiety about disease and death. Among family members, 26% are diagnosed with psychiatric disorders (depressive and anxiety disorders), and 23% with medical conditions, in the year preceding onset of conversion disorder; a family history of conversion disorder was found in 3%[2]. Boys have higher rates of poor interpersonal relations and communication problems within the family, and girls have higher rates of conflicts with the parents and other family members; sibling rivalry is found in 23.4% [2].
Stress factors Stress factors are diversely found [2,12,13,19,36], in 10% [12] to 90% [2,35]: school stress (12.5% to 58% [13,19,24] including bullying or victimization in school, 23.8% [2]), relational stress (52.5% [35]), medical diseases in relatives (25% [35]), parental separation 19% [2] and death of a relative or friend 16.7% [2]. Among 73.4% of cases with identifiable stressors in somatoform disorders, 14.5% had acute precipitating stressors, with an even higher proportion in conversion disorder [2]. What is remarkable and less known is that less abuse is found in children than in adults (4% [19], 6.6% [2], to 32% in PNES [47]). However, none of the authors considers puberty as an internal stress factor, except Bertrand Cramer in his remarkable clinical paper [1977,5].
Comorbidities Comorbidities are the usual ones found also in adult cases: 45% [35], more frequent anxiety disorders than depressive disorder (37.2% versus 15.7% [36], 18.2% versus 8.8% [2]), with psychotropic medication (55% [35], 14% [19]). Ani et al. found no mental disorder prior to the episode in 78% [2].
Favorable prognosis Some factors are associated with favorable prognosis: young age, sensory rather than motor symptoms, acuteness of presentation, onset precipitated by a stressful event, good premorbid health, good socio-economic status, absence of any other concomitant organic disease or major psychiatric symptoms — especially depression, absence of personality disorder [3,24,35,43,47]. Ani et al. found a new psychiatric disorder during the one-year follow-up period in 28% (anxiety disorder 14%, depressive disorder 13%, school phobia 9%) [2].
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Unresolved questions concerning conversive disorders Many questions remain concerning the process of conversive disorders.
Functional loss, or excess? What determines the nature of the symptom? Some patients show a lack of function (such as paralysis or sensory impairment), and other show positive symptoms (pain, abnormal movements, PNES, etc.). Some suggestions have been made to explain this. The symptom could be determined by a previous organic symptom (such as tendinitis or fracture), or could be ‘‘borrowed’’ from a relative, what Freud and Breuer (1895) called ‘‘somatic compliance’’ [25]. This idea can also be linked to Damasio’s theory of somatic markers (1994, [7]). Somatic markers are associations between reinforcing stimuli, somatic experiences that induce an associated physiologic affective state, which bias the way in which a further similar experience will be interpreted and thus the decision of how to act. Kozlowska has put forward one of the most interesting proposals [18,21]: that conversive symptoms during childhood or adolescence could be a sensori-motor component of two different ethological organizations. She refers to Kretschmer [23] and Nijenhuis et al. [33], these authors having already proposed that negative symptoms in conversion disorders could be seen as components of the animal ‘freezing response’. However, Kozlowska also refers to Morris et al. [31], who propose that ‘‘conversion positive symptoms could be related to a different type of animal behaviour called ‘behavioural deception’ or ‘deceptive signaling’, a behaviour that conveys ‘false’ information to a receiver, like an exaggerated behavioural display, to attract attention and to confuse the predator by the use of false signals’’ [18]. Kozlowska [21] proposes to extend this ethological point of view in the perspective of human development, referring to Crittenden’s dynamic-maturational model of attachment, a theory about protecting oneself from danger [6]. This model analyses development through ‘the interactive effects of genetic inheritance, maturational processes and person-specific experiences to produce individual differences in strategies for keeping oneself safe’ ([6], p. 105). They distinguish two types of defensive strategies against fear in animals: type A, being an inhibitory, immobilization or ‘‘freezing response’’; the second type, B, consisting of activatory, diversion ‘‘appeasement defense behavior’’. In a convincing way, Kozlowska [22] showed two distinct subtypes of conversion patients: those using psychological inhibition and those using psychological coercionpreoccupation, whose symptoms fell into discrete clusters. In this way, the nature of the conversive symptoms can be understood in the framework of an ethological/attachment system.
Does the neurobiology of conversion disorders shed light on conversive processes? In this special journal issue, Vuilleumier and Voon describe the current state of neural mechanism findings concerning
414 adult conversive disorders. The aim of this paper is not to discuss these results (see Vuilleumier in this issue for this review), but simply to make some comments. It remains difficult to reach a final conclusion, for many reasons. There are still few studies in this field, and they concern very few patients (although numbers included are tending to increase; maximum 16 patients, [45]). The paradigms proposed are rather sophisticated [4,44] and studies tend to focus, except Voon et al. [45], on negative symptoms. We probably face the first step of brain exploration of conversive disorders, because the research focuses on the manifest symptom (motor, sensory), but not on the underlying process. These studies shed light more on neural correlations during conversive disorders, than on the symptom production processes. Since conversive disorders lack a relevant theoretical framework, we do not have research paradigms that are relevant in terms of underlying pathopsychological processes. Why do most researchers focus on the symptom, grouping together patients only with similar symptoms, despite the fact that we include in the same conversion diagnosis patients with different symptoms? Why do they focus on the symptomatic result of the disease, instead of building paradigms relevant to etiological hypotheses? The most convincing theoretical framework that has already proposed a coherent theory of conversion is a psychodynamic one (Freud, Breuer 1895, [9]): that conversion could be produced by a repression mechanism of unbearable representations, converting these into somatic features. Researchers are familiar with cognitive paradigms: one hypothesis, one paradigm, one task that tests it. Are psychoanalysts ready to work with neuroscientists, and the most important: are neuroscientists ready to test psychodynamic hypotheses? Some have already constructed neurophysiological or MRI paradigms that test repression, referring to primary/secondary processes [39] or to Jung [15,38], who proposed that the level of physiological arousal during free association indicates whether contents are related to repressed conflicts. We propose in Table 1 a correspondence between theoretical psychodynamic frameworks and hypotheses, and paradigms that should be tested.
What are the challenges? The interest of child and adolescent conversive disorders At least 2 kinds of challenges remain: theoretical and clinical. The technical challenges (paradigms, MRI, etc.) are no longer a problem when the right questions are asked. The main challenge is to redefine our theoretical frameworks. Without any coherent theory, we cannot build coherent paradigms. The study of child and adolescents conversive disorders can help us to go deeper into the theory, for many reasons: • it allows evaluation of the ‘‘real’’ psychopathological process at its roots, not yet hidden by many defensive and rationalizating attitudes; • most of the conversive roots are anchored in early child and adolescent experience, and processes, such as
L. Ouss, E. Tordjman Table 1 Correspondence between theoretical psychodynamical frames, hypotheses and paradigms. Theory (Freud/Breuer, 1895 [9])
Paradigm proposition
Somatic compliance/embodied memories
Somatic markers, procedural memory, encoding paradigms Trauma paradigms (episodic memory) Episodic memory with emotional and sexual stimuli: retrieval paradigms Resting state that assesses default mode network; connectivity analysis [10,30] Attentional paradigms
Traumatic experience ‘‘Hysterics suffer from reminiscences’’
Variations in ‘‘intracerebral tonic excitation’’ (Breuer, in 1895 [9]) Attentional bias, (Breuer, in 1895 [9]) Symbolisation in conversion versus no symbolisation Repression
Primary/secondary processes paradigms Repression paradigm
attachment behavior and representations, which are difficult to explore many years later; • environmental features are easier to explore, when family is involved and can help to understand such a process. No neurophysiological studies have been yet carried out on children and adolescents, for ethical reasons, and for practical ones (less patients, shorter period of symptoms, better prognosis, dental braces, etc.). We have to better characterize the clinical presentation of conversive patients, according to the nature of the symptom (for example, positive or negative; motor, sensory, cognitive, etc.). We must also evaluate comorbidities; cognitive functioning [20]; psychic organization; and attachment style. We should study what is common to different conversion disorders in terms of profiles or processes, rather than what is common to symptoms. The symptom is only the final expression of a complex process.
A synthesis? A complementarist approach Fig. 1 represents a proposition of the whole complex process of conversive disorder. Kozlowska [17] has begun to describe this and we integrate some of the stages she proposes. However, she never refers to psychodynamic theory, or to repression, which probably remains a core process. Afferent information coming from sensory pathways, triggered by external or internal stimuli, are stored as ‘‘body states’’, which are processed and represented within the cognitive system [20] and underlying neural substrate [17]. These body states depend also on preceding early experiences, above all those that are traumatic or not yet transformed. In some conditions, depending on attachment style, or triggering events (internal events like puberty, or external emotional events, which sometimes refer to early traumatic or unelaborated experience), these
Conversive disorders among children and adolescents
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Figure 1 The whole process of conversion symptom production [in blue, the neural and cognitive levels. In purple, environmental level. In green, attachment level. In orange, symptomatic level. Blue rectangles signal processes. Red stars signal therapeutical levels].
dormant representations bias cognitive and neural processing of new information [17]. These representations are sometimes repressed; when unbearable, the early experience is sometimes directly re-enacted as bodily symptoms. New information is re-interpreted as the subjective experience of an involuntary symptom, and sometimes re-expressed similarly to the previous event, in an analogous way; for example, previous experience of motor loss in a limb, that is subsequently behaviorally expressed as motor, sensory or cognitive symptoms. We could then propose a different focus of therapy: memory and trauma integration to elaborate the traumatic process; trans-magnetic stimulation (TMS) to directly reach the neural system (despite the fact that there is insufficient good quality evidence to establish TMS as an effective treatment modality [37]); attachment therapy that can influence the behavioral expression; family guidance to elaborate the environmental features; psychodynamic psychotherapy for repression; and physiotherapy to directly treat the symptom. The principal interest of this model is to propose a complementarist approach in order to combine different levels (neural, cognitive, environmental, attachment, intrapsychic) [34]. ‘‘Complementarism’’ (Devereux, in 1972 [8]) was first used in an ethno-psychiatric framework. Devereux describes a position that necessarily takes into account two theoretical frames, but not simultaneously. Successive shifts allows us to take one position, and then another. This is not a choice; it is a necessary position, an inevitable methodology that allows one to study the same object from two different points of view without equating one to the other. This approach also allows differentiation of different kinds of therapeutic targets and means. We propose an
‘‘and-and’’, rather than an ‘‘or-or’’ epistemology: we have to take into account both the neurophysiological and the intra-psychic levels, to understand the process of symptom production. Most authors propose the promotion of a multidisciplinary collaboration between pediatricians, psychologists and psychiatrists. We go further in arguing that each level corresponds to a therapeutic proposition. We might thus question whether we should try to cure defensive symptoms or not: it is often necessary to respect the symptom, until we understand its role. Such respect however does not mean that we do not attempt to cure it. On the other hand, we have to remain aware that if the symptom has any role in the psyche, its rapid disappearance without any psychic elaboration will certainly be followed by the reappearance of another symptom. In conclusion, clinicians and neurophysiologists have to work together to try, if possible, to deepen their understanding of conversive patients.
Disclosure of interest The authors declare that they have no conflicts of interest concerning this article.
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