Psychomotor symptoms of depression

The global prevalence of depressive disorders and their accompanying comorbidities and their complicated aetiology and inter-individual heterogeneity in responsiveness to pharmaceutical therapies need the development of novel treatments. Non-invasive brain stimulation treatments have developed as therapeutic alternatives, aided by a growing understanding of mood-regulating mechanisms. Because of its excellent safety–feasibility profile and capacity to produce functional changes in resting membrane potential and cerebral blood flow, transcranial direct current stimulation (tDCS) has received much investigation over the last decade.

  • Experimental Design

A randomized, double-blind, sham-controlled experiment aimed at investigating the effect of 10 sessions of tDCS administered over the left dlPFC on PMR in unipolar depression. Following completion of baseline clinical and experimental measurements, individuals were randomly allocated to receive either active or sham tDCS (in addition to their pharmaceutical therapy) using a computer-generated randomization list and data kept on a centralized computer.

  • Transcranial Direct Current Stimulation

A battery-powered constant-current stimulator and saline-soaked sponge electrodes were employed by researchers at the University of California, San Diego. According to the worldwide 10–20 EEG System, the anode was positioned over the left dlPFC, and the cathode was placed completed the contralateral supraorbital region, corresponding to F3 and FP2, respectively. In the active group, stimulation intensity was set to 2 mA for 30 minutes twice a day for 5 days. The sham stimulation technique was identical, except that the current was progressively scaled down to zero, producing the same feelings as tDCS.

  • Psychiatric Assessment

A professional psychiatrist assessed depression severity and PMR at baseline (T1) and immediately after therapy ended (T2). Depression rating scales included the 21-item HDRS, the MADRS, and the Beck Depression Inventory (BDI). The Salpêtrière Retardation Rating Scale was used to assess PMR (SRRS)

References

Bennabi, Djamila, et al. “Influence of Transcranial Direct Current Stimulation on Psychomotor Symptoms in Major Depression.” Brain Sciences 10.11 (2020): 792.