Cognitive and Emotional Effects of tDCS in Depressed vs. Non-depressed Individuals: A Comparative fMRI Study

Diax Caolina^*
*Correspondence: Diax Caolina, Department of Psychology, Airlangga University, Surabaya, Indonesia, Email:

Introduction

Major Depressive Disorder (MDD) is a prevalent and debilitating psychiatric condition that significantly impairs an individual's emotional, cognitive, and physical functioning. It is characterized by persistent low mood, loss of interest or pleasure in activities, and other debilitating symptoms such as sleep disturbances, fatigue, and cognitive deficits. Among individuals diagnosed with depression, there is often a marked reduction in cognitive functioning, including memory, attention, and executive functioning. Furthermore, depressive individuals commonly exhibit heightened emotional reactivity, particularly in response to negative stimuli. These cognitive and emotional impairments are not only a hallmark of depression but also contribute to the chronicity and severity of the disorder. As the demand for effective treatments grows, novel interventions such as transcranial Direct Current Stimulation (tDCS) have emerged as potential solutions, showing promise in modulating brain activity and improving mood and cognitive function [1].

Description

tDCS is a non-invasive neuromodulation technique that applies a low-intensity electrical current to specific regions of the brain via electrodes placed on the scalp. The goal of tDCS is to modulate neuronal excitability in targeted brain areas, which has been shown to have therapeutic effects for a range of neurological and psychiatric conditions, including depression. In particular, the Dorsolateral Prefrontal Cortex (DLPFC) has been a frequent target of tDCS studies in the context of depression. The left DLPFC, in particular, has been associated with positive affect regulation and cognitive control, while the right DLPFC has been linked to the regulation of negative emotions. In individuals with MDD, decreased activity in the left DLPFC and increased activity in the right DLPFC are frequently observed, and these neural abnormalities are thought to contribute to the cognitive and emotional symptoms of the disorder. By applying anodal stimulation to the left DLPFC and cathodal stimulation to the right DLPFC, tDCS aims to rebalance the neural activity in these areas, potentially improving both cognitive performance and emotional regulation [2].

Despite the growing body of evidence supporting the use of tDCS for depression, the mechanisms underlying its effects remain only partially understood. The role of tDCS in modulating cognition and emotion in individuals with depression, compared to healthy individuals, has not been thoroughly explored. One particularly useful tool for examining these mechanisms is functional Magnetic Resonance Imaging (fMRI), which allows for the non-invasive measurement of brain activity during cognitive and emotional tasks. fMRI studies have provided valuable insights into how tDCS affects brain function in depressed versus non-depressed individuals, shedding light on the differential impacts of this neuromodulation technique across varying psychiatric conditions. In this context, comparative studies using fMRI to explore the cognitive and emotional effects of tDCS in both depressed and non-depressed individuals could offer important insights into its therapeutic potential and guide its clinical application [3].

This research article explores the cognitive and emotional effects of tDCS in depressed and non-depressed individuals, with a focus on understanding the differential neural responses to tDCS. By utilizing fMRI as a primary tool, this study aims to investigate how tDCS influences brain activity in response to cognitive and emotional tasks in both groups. Specifically, we aim to examine how tDCS affects areas of the brain involved in emotion regulation, such as the prefrontal cortex and limbic structures, and cognitive processes like attention, memory, and executive function. Furthermore, by comparing the effects of tDCS in depressed and non-depressed individuals, this research seeks to elucidate whether tDCS produces similar or divergent neural changes across different populations and whether these effects correlate with improvements in mood and cognitive functioning [4,5].

Conclusion

In conclusion, this comparative fMRI study of the cognitive and emotional effects of tDCS in depressed and non-depressed individuals aims to provide critical insights into the mechanisms that underlie the therapeutic potential of this neuromodulation technique. By examining the differential effects of tDCS on brain activity in response to cognitive and emotional tasks, this research seeks to advance our understanding of how tDCS influences brain function in individuals with depression compared to healthy individuals. The findings from this study could inform the development of more effective, personalized treatment protocols for depression and provide a deeper understanding of the neural changes that underlie improvements in mood and cognition. Given the growing interest in tDCS as a treatment for depression, particularly in treatment-resistant cases, this research has the potential to shape future clinical approaches and contribute to the broader field of neurotherapeutics. As research into neuromodulation continues to evolve, the integration of tDCS with advanced neuroimaging techniques such as fMRI will be instrumental in optimizing the use of this promising intervention.

Acknowledgment

None.

Conflict of Interest

None.

References

1. Valiengo, Leandro, Isabela Martins Benseñor, Alessandra C. Goulart and Janaina Farias de Oliveira, et al. "The sertraline versus electrical current therapy for treating depression clinical study (selectâ?TDCS): Results of the crossover and followâ?up phases." Depress Anxiety30 (2013): 646-653.

Google Scholar Cross Ref Indexed at

2. Kalu, U. G., C. E. Sexton, C. K. Loo and K. P. Ebmeier. "Transcranial direct current stimulation in the treatment of major depression: A meta-analysis." Psychol Med 42 (2012): 1791-1800.

Google Scholar Cross Ref Indexed at

3. Berlim, Marcelo T., Frederique Van den Eynde and Z. Jeff Daskalakis. "Clinical utility of transcranial direct current stimulation (tDCS) for treating major depression: a systematic review and meta-analysis of randomized, double-blind and sham-controlled trials." J Psychiatr Res 47 (2013): 1-7.

Google Scholar Cross Ref Indexed at

4. Shiozawa, Pedro, Felipe Fregni, Isabela M. Benseñor and Paulo A. Lotufo, et al. "Transcranial direct current stimulation for major depression: An updated systematic review and meta-analysis." Int J Neuropsychopharmacol 17 (2014): 1443-1452.

Google Scholar Cross Ref Indexed at

5. Meron, Daniel, Nicholas Hedger, Matthew Garner and David S. Baldwin. "Transcranial direct current stimulation (tDCS) in the treatment of depression: Systematic review and meta-analysis of efficacy and tolerability." Neurosci Biobehav Rev 57 (2015): 46-62.

 Google Scholar Cross Ref Indexed at