Electroconvulsive therapy with a memory reactivation intervention for post-traumatic stress disorder: A randomized controlled trial

Esketamine-induced post-traumatic stress disorder flashbacks during treatment-resistant depression indication: is it just a side effect?

Background

Posttraumatic stress disorder (PTSD) is a severe and frequent affection that is highly comorbid to major depressive disorder. Comorbid PTSD and depression are usually treatment-resistant, with a high risk of functional impairment and suicide. Esketamine nasal spray is a recent validated treatment for treatment-resistant depression (TRD), but its efficacy on comorbid TRD-PTSD remains insufficiently documented. In particular, flashbacks can occur during esketamine administration and their influence on clinical outcomes is unknown.

Objectives

Our main objective was to describe esketamine-induced traumatic flashbacks and their impact on clinical trajectories within a sample of patients with comorbid TRD-PTSD.

Methods

We retrospectively collected clinical data of patients receiving esketamine nasal spray for TRD with comorbid PTSD who experienced at least one flashback of their trauma during esketamine sessions across 11 psychiatric departments.

Results

Between February 2020 and March 2023, 22 adult patients with TRD met inclusion criteria. In sixteen patients (72.7%) flashbacks disappeared as the sessions progressed. In six patients (27.3%), esketamine treatment was stopped because of persistent flashbacks. When esketamine was continued, clinical response was observed both for depression and PTSD (depression response rate: 45.5% and remission rate: 22.7%; PTSD response rate: 45.5% and remission: 18.2%).

Limitations

The retrospective design of the study and the absence of a comparator group are the main limitations of our study.

Conclusions

Our results suggest that the occurrence of esketamine-induced traumatic flashbacks does not hinder clinical response. On the contrary, when managed appropriately and combined with targeted psychotherapy, it could even contribute to positive outcomes.

The influence of electroconvulsive therapy on reconsolidation of autobiographical memories: A retrospective quasi-experimental study in patients with depression

Background/Objective

Electroconvulsive therapy (ECT) is effective for treatment-resistant and psychotic depression. One previously reported side effect of ECT is the disruption of memory reconsolidation. This study examines whether this disruption induced by ECT can be detected in routine neuropsychological assessments.

Methods

In this retrospective study, the Autobiographical Memory Interview (AMI) was applied before and after ECT. Memories of the same events and facts were tested pre and post ECT treatments. 38 patients, receiving ECT for the treatment of unipolar or bipolar depression, were matched for age, sex, and stimulus intensity and divided into two groups: Group A was tested on the day before the first ECT treatment, whereas group B two or more days before.

Results

Patients who were tested by AMI on the day before ECT and thus reactivated memorie shortly before the first ECT treatment deteriorated in AMI score. Patients who had at least two days between memory activation and treatment improved regarding the number of recalled memories. Memory impairment was not associated with depression severity.

Conclusion

This finding suggests that ECT might be capable of impairing reconsolidation. The study demonstrates that memories of personal events can potentially be affected by ECT within a time interval of 24 h of memory vulnerability after reactivation. Implications for practice and future research are discussed.

Traumatic memory retrieval followed by electroconvulsive therapy as a treatment for posttraumatic stress disorder: A pilot study

Delivering electroconvulsive therapy (ECT) during the reconsolidation of traumatic memories may enhance the treatment efficacy in posttraumatic stress disorder (PTSD). To test this, 14 patients with severe and refractory PTSD were randomly allocated to receive ECT sessions either after retrieving the traumatic (n=8) or a neutral (n=6) memory. We found that delivering ECT after retrieving the traumatic memory enhanced the improvement of PTSD symptoms and the reduction of subjective reactivity to the traumatic memory. Reduction in anxiety and mood symptoms and physiological reactivity to the traumatic memory were observed in the sample as a whole regardless of memory retrieval.

Heat exposure following encoding can interfere with subsequent recognition memory

Correlational studies suggest that high temperatures may impair online cognitive performance and learning processes. Here, we tested the hypothesis that heat exposure blocks offline memory consolidation. We report two studies, including a pre-registered replication. First, during a study phase, participants were familiarized with neutral and negatively valenced images. One day later, half of the participants were exposed to high temperatures in a sauna session at 50 °C. Recognition memory was tested 24 h later. We found that participants exposed to high temperature showed an impairment in recognition memory performance, relative to a control group of participants that were not exposed to heat or that had a sauna at 28 °C. This occurred for both emotional and neutral items. These results indicate that heat exposure impairs memory consolidation, thereby opening the possibility of using heat exposure as an agent for the treatment of clinical mental disorders.

Evaluating the effect of electroconvulsive therapy (ECT) on post-traumatic stress disorder (PTSD): A systematic review and meta-analysis of five studies

ECT has been proposed as a potential treatment for PTSD. There is a small number of clinical studies to date, but no quantitative review of the efficacy has been conducted. We performed a systematic review and meta-analysis to evaluate the effect of ECT in reducing PTSD symptoms. We followed the PICO and the PRISMA guidelines and searched PubMed, MEDLINE (Ovid), EMBASE (Ovid), Web of Science, and the Cochrane Central Register of Controlled Trials (PROSPERO No: CRD42022356780). A random effects model meta-analysis was conducted with the pooled standard mean difference, applying Hedge's adjustment for small sample sizes. Five within-subject studies met the inclusion criteria, containing 110 patients with PTSD symptoms receiving ECT (mean age 44.13 ± 15.35; 43.4% female). ECT had a small but significant pooled effect on reducing PTSD symptoms (Hedges' g = -0.374), reducing intrusion (Hedges' g = -0.330), avoidance (Hedges' g = -0.215) and hyperarousal (Hedges' g = -0.171) symptoms. Limitations include the small number of studies and subjects and the heterogeneity of study designs. These results provide preliminary quantitative support for the use of ECT in the treatment of PTSD.

Contemporary Approaches Toward Neuromodulation of Fear Extinction and Its Underlying Neural Circuits

Neuroscience and neuroimaging research have now identified brain nodes that are involved in the acquisition, storage, and expression of conditioned fear and its extinction. These brain regions include the ventromedial prefrontal cortex (vmPFC), dorsal anterior cingulate cortex (dACC), amygdala, insular cortex, and hippocampus. Psychiatric neuroimaging research shows that functional dysregulation of these brain regions might contribute to the etiology and symptomatology of various psychopathologies, including anxiety disorders and post traumatic stress disorder (PTSD) (Barad et al. Biol Psychiatry 60:322-328, 2006; Greco and Liberzon Neuropsychopharmacology 41:320-334, 2015; Milad et al. Biol Psychiatry 62:1191-1194, 2007a, Biol Psychiatry 62:446-454, b; Maren and Quirk Nat Rev Neurosci 5:844-852, 2004; Milad and Quirk Annu Rev Psychol 63:129, 2012; Phelps et al. Neuron 43:897-905, 2004; Shin and Liberzon Neuropsychopharmacology 35:169-191, 2009). Combined, these findings indicate that targeting the activation of these nodes and modulating their functional interactions might offer an opportunity to further our understanding of how fear and threat responses are formed and regulated in the human brain, which could lead to enhancing the efficacy of current treatments or creating novel treatments for PTSD and other psychiatric disorders (Marin et al. Depress Anxiety 31:269-278, 2014; Milad et al. Behav Res Ther 62:17-23, 2014). Device-based neuromodulation techniques provide a promising means for directly changing or regulating activity in the fear extinction network by targeting functionally connected brain regions via stimulation patterns (Raij et al. Biol Psychiatry 84:129-137, 2018; Marković et al. Front Hum Neurosci 15:138, 2021). In the past ten years, notable advancements in the precision, safety, comfort, accessibility, and control of administration have been made to the established device-based neuromodulation techniques to improve their efficacy. In this chapter we discuss ten years of progress surrounding device-based neuromodulation techniques-Electroconvulsive Therapy (ECT), Transcranial Magnetic Stimulation (TMS), Magnetic Seizure Therapy (MST), Transcranial Focused Ultrasound (TUS), Deep Brain Stimulation (DBS), Vagus Nerve Stimulation (VNS), and Transcranial Electrical Stimulation (tES)-as research and clinical tools for enhancing fear extinction and treating PTSD symptoms. Additionally, we consider the emerging research, current limitations, and possible future directions for these techniques.

The GR-FKBP51 interaction modulates fear memory but not spatial or recognition memory

The glucocorticoid receptor (GR) forms a protein complex with FKBP51 that is increased in post-traumatic stress disorder (PTSD) and by fear conditioned learning. Disrupting the GR-FKBP51 complex with a synthetic peptide can block the storage or retrieval of fear conditioned memories, which could be a novel approach to the alleviate fear associated memory in PTSD. However, a potential unacceptable side effect could be the impairment of other types of memory. Thus, we investigated the effect of disrupting the GR-FKBP51 complex on recognition memory using the novel object and displaced object recognition tasks, spatial memory in the Morris water maze, and on social interaction in Crawley's three-chamber social interaction test. We did not observe adverse effects on these other types of memory and conclude that the GR-FKBP51 interaction remains a promising target for treating psychiatric disorders characterized by unwanted aversive memories such as in PTSD.

Appraising reconsolidation theory and its empirical validation

Re-exposure to elements of prior experiences can create opportunities for inducing amnesia for those events. The dominant theoretical framework posits that such re-exposure can result in memory destabilization, making the memory representation temporarily sensitive to disruption while it awaits reconsolidation. If true, such a mechanism that allows for memories to be permanently changed could have important implications for the treatment of several forms of psychopathology. However, there have been contradictory findings and elusive occurrences of replication failures within the "reconsolidation" field. Considering its potential relevance for clinical applications, the fact that this "hot" research area is being dominated by a single mechanistic theory, and the presence of unexplainable contradictory findings, we believe that it is both useful and timely to critically evaluate the reconsolidation framework. We discuss potential issues that may arise from how reconsolidation interference has typically been deducted from behavioral observations, and provide a principled assessment of reconsolidation theory that illustrates that the theory and its proposed boundary conditions are vaguely defined, which has made it close to impossible to refute reconsolidation theory. We advocate for caution, encouraging researchers not to blindly assume that a reconsolidation process must underlie their findings, and pointing out the risks of doing so. Finally, we suggest concrete theoretical and methodological advances that can promote a fruitful translation of reminder-dependent amnesia into clinical treatment.

Invisible wounds: Suturing the gap between the neurobiology, conventional and emerging therapies for posttraumatic stress disorder

A sharp increase in the prevalence of neuropsychiatric disorders, including major depression, anxiety, substance use disorders and posttraumatic stress disorder (PTSD) has occurred due to the traumatic nature of the persisting COVID-19 global pandemic. PTSD is estimated to occur in up to 25% of individuals following exposure to acute or chronic trauma, and the pandemic has inflicted both forms of trauma on much of the population through both direct physiological attack as well as an inherent upheaval to our sense of safety. However, despite significant advances in our ability to define and apprehend the effects of traumatic events, the neurobiology and neuroanatomical circuitry of PTSD, one of the most severe consequences of traumatic exposure, remains poorly understood. Furthermore, the current psychotherapies or pharmacological options for treatment have limited efficacy, durability, and low adherence rates. Consequently, there is a great need to better understand the neurobiology and neuroanatomy of PTSD and develop novel therapies that extend beyond the current limited treatments. This review summarizes the neurobiological and neuroanatomical underpinnings of PTSD and discusses the conventional and emerging psychotherapies, pharmacological and combined psychopharmacological therapies, including the use of psychedelic-assisted psychotherapies and neuromodulatory interventions, for the improved treatment of PTSD and the potential for their wider applications in other neuropsychiatric disorders resulting from traumatic exposure.