Electroconvulsive Therapy in Psychiatric Disorders: A Narrative Review Exploring Neuroendocrine–Immune Therapeutic Mechanisms and Clinical Implications

Electroconvulsive Therapy Modulates Loudness Dependence of Auditory Evoked Potentials: A Pilot MEG Study

Electroconvulsive therapy (ECT) remains a critical intervention for treatment-resistant depression (MDD), yet its neurobiological underpinnings are not fully understood. This pilot study utilizes high-resolution magnetoencephalography (MEG) in nine depressed patients receiving right unilateral ECT, to investigate the changes in loudness dependence of auditory evoked potentials (LDAEP), a proposed biomarker of serotonergic activity, following ECT. We hypothesized that ECT would reduce the LDAEP slope, reflecting enhanced serotonergic neurotransmission. Contrary to this, our findings indicated a significant increase in LDAEP post-ECT ( t 8 = 3.17, p = .013). The increase in LDAEP was not associated with changes in depression severity or cognitive performance, as assessed by the Hamilton Depression Rating Scale (HAMD-24) and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). We discussed potential mechanisms for the observed increase, including ECT's impact on serotonergic, dopaminergic, glutamatergic, and GABAergic receptor activity, neuroplasticity involving brain-derived neurotrophic factor (BDNF), and inflammation modulators such as TNF- alpha . Our results suggest a complex interaction between ECT and these neurobiological systems, rather than a direct reflection of serotonergic neurotransmission.

Mechanism of electroconvulsive therapy in schizophrenia: a bioinformatics analysis study of RNA-seq data

OBJECTIVE

The molecular mechanism of electroconvulsive therapy (ECT) for schizophrenia remains unclear. The aim of this study was to uncover the underlying biological mechanisms of ECT in the treatment of schizophrenia using a transcriptional dataset.

METHODS

The peripheral blood mRNA sequencing data of eight patients (before and after ECT) and eight healthy controls were analyzed by integrated co-expression network analysis and the differentially expressed genes were analyzed by cluster analysis. Gene set overlap analysis was performed using the hypergeometric distribution of phypfunction in R. Associations of these gene sets with psychiatric disorders were explored. Tissue-specific enrichment analysis, gene ontology enrichment analysis, and protein-protein interaction enrichment analysis were used for gene set organization localization and pathway analysis.

RESULTS

We found the genes of the green-yellow module were significantly associated with the effect of ECT treatment and the common gene variants of schizophrenia ( P  = 0.0061; family-wise error correction). The genes of the green-yellow module are mainly enriched in brain tissue and mainly involved in the pathways of neurotrophin, mitogen-activated protein kinase and long-term potentiation.

CONCLUSION

Genes associated with the efficacy of ECT were predominantly enriched in neurotrophin, mitogen-activated protein kinase and long-term potentiation signaling pathways.

Neurobiological mechanisms and therapeutic impact of electroconvulsive therapy (ECT)

Electroconvulsive therapy (ECT) is an efficient therapeutic resource for psycho-pharmacotherapeutic resistant forms of depression. ECT is a form of electrical brain stimulation involving the induction of a controlled seizure, clinically similar to an epileptic seizure, that is initiated in the prefrontal region of the brain and spreads to the cortex and subcortex, including the diencephalic structures. This is achieved by creating a transcranial electric field and synchronously depolarizing neuronal membranes. The mechanisms of action of ECT are not yet fully understood, but several hypotheses have been proposed to explain how it affects the brain: neurotransmitter changes, neuroplasticity, network connectivity, endocrine system regulation and changes in regional cerebral blood flow and regional metabolism.

Molecular and immunological origins of catatonia

Catatonia occurs secondary to both primary psychiatric and neuromedical etiologies. Emerging evidence suggests possible linkages between causes of catatonia and neuroinflammation. These include obvious infectious and inflammatory etiologies, common neuromedical illnesses such as delirium, and psychiatric entities such as depression and autism-spectrum disorders. Symptoms of sickness behavior, thought to be a downstream effect of the cytokine response, are common in many of these etiologies and overlap significantly with symptoms of catatonia. Furthermore, there are syndromes that overlap with catatonia that some would consider variants, including neuroleptic malignant syndrome (NMS) and akinetic mutism, which may also have neuroinflammatory underpinnings. Low serum iron, a common finding in NMS and malignant catatonia, may be caused by the acute phase response. Cellular hits involving either pathogen-associated molecular patterns (PAMP) danger signals or the damage-associated molecular patterns (DAMP) danger signals of severe psychosocial stress may set the stage for a common pathway immunoactivation state that could lower the threshold for a catatonic state in susceptible individuals. Immunoactivation leading to dysfunction in the anterior cingulate cortex (ACC)/mid-cingulate cortex (MCC)/medial prefrontal cortex (mPFC)/paralimbic cortico-striato-thalamo-cortical (CSTC) circuit, involved in motivation and movement, may be particularly important in generating the motor and behavioral symptoms of catatonia.

[Practice of anaesthesia for electroconvulsive therapy]

Electroconvulsive therapy (ECT) is an established therapeutic method for the treatment of severe mental disorders refractory to pharmaco- and psychotherapy. ECT is a first-line treatment option in delusional disorders, severe depression with acute suicidal tendency or life-threatening catatonia. Usually, ECT is performed as a treatment series. Under short-term anaesthesia and muscle relaxation, tonic-clonic seizures are induced using an external stimulation electrode. Convulsion can be exerted by uni- or bipolar stimulation using an electric charge up to 1000 millicoulomb (mC) with an amperage of 900 mA. Muscular relaxation is necessary to prevent injuries caused by uncontrolled movements during convulsion. During paralysis, consciousness is blocked by general anaesthesia, although ECT is associated with antegrade amnesia for seizure induction and the seizure itself. In the context of ECT, the ideal hypnotic should be characterised by rapid onset, short duration of action and negligible anticonvulsive effects (i.e., least possible impact on seizure quality and duration). As mutual awareness of psychiatric and anaesthesiologic techniques is essential for safe and effective conduction of ECT, this article presents ECT both from the psychiatrist's and the anaesthesiologist's perspective.

Non-Invasive Neuromodulation Methods to Alleviate Symptoms of Huntington's Disease: A Systematic Review of the Literature

Huntington's disease (HD) is a progressive and debilitating neurodegenerative disease. There is growing evidence for non-invasive neuromodulation tools as therapeutic strategies in neurodegenerative diseases. This systematic review aims to investigate the effectiveness of noninvasive neuromodulation in HD-associated motor, cognitive, and behavioral symptoms. A comprehensive literature search was conducted in Ovid MEDLINE, Cochrane Central Register of Clinical Trials, Embase, and PsycINFO from inception to 13 July 2021. Case reports, case series, and clinical trials were included while screening/diagnostic tests involving non-invasive neuromodulation, review papers, experimental studies on animal models, other systematic reviews, and meta-analyses were excluded. We have identified 19 studies in the literature investigating the use of ECT, TMS, and tDCS in the treatment of HD. Quality assessments were performed using Joanna Briggs Institute's (JBI's) critical appraisal tools. Eighteen studies showed improvement of HD symptoms, but the results were very heterogeneous considering different intervention techniques and protocols, and domains of symptoms. The most noticeable improvement involved depression and psychosis after ECT protocols. The impact on cognitive and motor symptoms is more controversial. Further investigations are required to determine the therapeutic role of distinct neuromodulation techniques for HD-related symptoms.