Nonepileptic seizures - subjective phenomena

Psychogenic nonepileptic seizures (PNES) superficially resemble epileptic seizures or syncope and most patients with PNES are initially misdiagnosed as having one of the latter two types of transient loss of consciousness. However, evidence suggests that the subjective seizure experience of PNES and its main differential diagnoses are as different as the causes of these three disorders. In spite of this, and regardless of the fact that PNES are considered a mental disorder in the current nosologies, research has only given limited attention to the subjective symptomatology of PNES. Instead, most phenomenologic research has focused on the visible manifestations of PNES and on physiologic parameters, neglecting patients' symptoms and experiences. This chapter gives an overview of qualitative and quantitative studies providing insights into subjective symptoms associated with PNES, drawing on a wide range of methodologies (questionnaires, self-reports, physiologic measures, linguistic analyses, and neuropsychologic experiments). After discussing the scope and limitations of these approaches in the context of this dissociative phenomenon, we discuss ictal, peri-ictal and interictal symptoms described by patients with PNES. We particularly focus on impairment of consciousness. PNES emerges as a clinically heterogeneous condition. We conclude with a discussion of the clinical significance of particular subjective symptoms for the engagement of patients in treatment, the formulation of treatment, and prognosis.