Structural and functional changes associated with functional/dissociative seizures: A review of the literature.

INTRODUCTION: The term 'functional/dissociative seizures (FDS)' refers to a paroxysmal, transient clinical manifestation that may include motor, sensory, vegetative, psychological and cognitive signs, similar to the manifestations observed in epileptic seizures. In recent years, there has been an increase of literature in the field of brain imaging research on functional neurological disorders and, more specifically, on FDS. However, most of the studies have been carried out on limited samples. We propose an update of this review work by performing a systematic review of studies performed since 2017 in the field of neuroimaging in patients with FDS. METHODS: We conducted a systematic review of the literature using the PRISMA methodology and reproduced most of the methodological elements of the latest systematic literature review. RESULTS: Our work over the last five years has identified 14 articles. It is still difficult to isolate a distinct structure or network specifically involved in the mechanism of FDS. However, certain structures are recurrently involved in imaging studies, notably the amygdala, the orbitofrontal cortex, and the anterior cingulate cortex. CONCLUSION: The contribution of neuroimaging may allow a more precise explanation of the disorder for patients, avoiding the stigma frequently associated with this diagnosis. as with other 'conversion' phenomena which have traditionally been considered only as 'medically unexplained'. In the longer term and beyond a better understanding of the physiopathology of the disorder, the challenge of this neuroimaging work would be to identify specific imaging biomarkers for a diagnosis of FDS.

Efficacy of traumatic memory reactivation with or without propranolol in PTSD with high dissociative experiences.

Background: Post-traumatic stress disorder (PTSD) with dissociative symptoms is now a full-fledged subtype of this disorder. The dissociative subtype is associated with a greater number of psychiatric comorbidities. To date, the impact of dissociation on the efficacy of PTSD treatment remains unclear.Objective: The aim of this study was to compare the efficacy of a traumatic memory reactivation procedure with the administration of propranolol or a placebo once a week for six consecutive weeks in reducing PTSD and MDE symptoms between PTSD subjects with or without high dissociative symptoms.Method: For that, we conducted a randomized clinical trial in 66 adults diagnosed with longstanding PTSD and measured the SCID PTSD module, the PTSD Checklist (PCL-S), Beck's Depression Inventory-II (BDI-II), and the Dissociative Experiences Scale (DES).Results: Patients with and without high dissociative experience had significant improvement in their PCL-S scores over the 6 treatment sessions, and PCL-S scores continued to decline in all patients during the post-treatment period. However, there was no correlation between the presence/absence of high dissociative experiences and no specific effect of propranolol treatment. We found exactly the same results for MDE symptoms. Interestingly, patients with high dissociative experiences before treatment exhibited very significant improvement in their DES scores after the 6 treatment sessions, and patients maintained this improvement 3 months post-treatment.Conclusions: The traumatic memory reactivation procedure is an effective way to treat dissociative symptoms in patients with PTSD, and improvement of these dissociative symptoms was associated with a decrease in both PTSD and depression severity.

Traumatic memory reactivation procedure is an effective way to treat dissociative symptoms in patients with PTSD.The improvement of these dissociative symptoms was associated to a decrease of both PTSD and depression severity.Dissociative symptoms do not seem to mitigate the efficacy of traumatic memory reactivation during the treatment of PTSD.