Comparisons of childhood trauma, alexithymia, and defensive styles in patients with psychogenic non-epileptic seizures vs. epilepsy: Implications for the etiology of conversion disorder

Abstract

Background

It has been theorized that conversion disorder is the result of emotion that cannot be experienced consciously as feeling states or put into words (i.e., alexithymia), but there is little confirming empirical evidence. We sought to characterize subjects with conversion disorder compared to subjects with a distinct medical illness, using the model of psychogenic non-epileptic seizures (PNES) vs. epilepsy (ES), on measures of childhood traumatic experience, alexithymia and maturity of psychological defensive strategies.

Methods

All subjects admitted to the Epilepsy Monitoring Unit of the University of Cincinnati Medical Center were offered self-report questionnaires (Childhood Trauma Questionnaire, Toronto Alexithymia Scale-20 and Response Evaluation Measure-71) at the outset of evaluation. Diagnosis of each subject was confirmed by video-EEG and we compared subjects with PNES to those with ES on these measures.

Results

82 subjects had ES AND 96 had PNES. Those with PNES were significantly more likely to have experienced childhood trauma in all domains (p = .005 to p = .05), and were significantly more likely to have alexithymia (p = .0267). There was a significant difference in the capacity to identify feelings, and a trend towards significance in capacity to describe feelings. There were no differences in defensive styles between the two groups.

Conclusions

PNES diagnosis was associated with female sex, higher alexithymia scores and higher rates of childhood trauma, but not with differences in defensive styles compared to ES. These findings add empirical evidence for theories regarding the cause of conversion disorder and may aid in the design of prospective treatment trials in patients with conversion disorder.

Introduction

Any medical illness is affected by one's psychic state, and psychosomatic processes dictate the subjective experience of even entirely “organic” illnesses. For instance, individuals with epilepsy may be more likely to have seizures, or individuals with coronary artery disease may sustain myocardial infarction when they are under stress. Conversion disorder assumes that there is no “organic” illness but symptoms are produced entirely by brain mechanisms as a way of expressing distress when psychic means are unavailable. In modern psychiatric nosology,¹ conversion disorder refers to the development of pseudo-neurologic symptoms without an organic basis. It is the heir to Freud and Breuer's concept of hysteria, first published in 1895 [1], [2] which proposed that conversion disorder symptoms were the result of a response to a precipitating trauma that could not be dealt with by psychic means.

Childhood trauma is the most robust empirically demonstrated correlate of conversion disorder [3], [4]. Conversion disorder symptoms may seem to mimic a traumatic experience, e.g., an incest victim who develops psychogenic non-epileptic seizures (PNES) with prominent pelvic thrusting and moaning that suggest intercourse. Conversion disorder symptoms may also symbolize psychological defense against the trauma, e.g., an individual angry at having tolerated repeated abuses by a parent but who fears abandonment if that anger is expressed, develops paralysis that protects against retaliation. Patients with conversion disorder have higher scores on several trauma scales and measures of dissociation [5], [6], [7], [8], [9], [10] and show evidence of hypervigilance to threat compared to healthy controls [11].

The concept of alexithymia, first coined by Sifneos [12], refers to difficulty perceiving, identifying and describing feeling states, difficulty distinguishing between feeling states and bodily experiences of emotional arousal, constricted capacity for emotional thought and fantasy development, and an externally oriented cognitive style. Alexithymia implies problems in the capacity for mentalization (the ability to understand that one has one's own thoughts and feelings, separate from others' thoughts and feelings, and that those mental processes motivate behavior in oneself and in others) [13] and associated psychic expression of affect. Instead of identifying internal feeling states creating tension or distress, the alexithymic individual attributes experience to external situations (e.g., physical illness).

Since conversion disorder symptoms appear to function as a defensive strategy that prevents awareness of psychic distress, most conversion disorder patients are unaware of psychic conflict that might be related to the symptom and do not seek psychological consultation in the face of unexplained physical symptoms. Those who are referred for psychological treatments often doubt that their symptoms are related to internal psychic processes. Individuals who develop conversion disorder symptoms would seem likely to use less mature defensive approaches (e.g., anticipation, sublimation, or suppression) to fend off psychic conflict, since theoretically they would be less capable of using psychic defense mechanisms for protection.

The authors hypothesized that individuals with conversion disorder would more likely have histories of early childhood trauma, alexithymia, and immature defensive styles, compared to those without conversion disorder, and that those with PNES would have greater childhood trauma and higher levels of alexithymia, and use less mature defenses than individuals with epileptic seizures (ES) only.