Subject state, including any concurrent therapy with tDCS, is considered important, since the effects of tDCS on the brain depend on the state of the brain. Subject condition also matters for similar reasons. For example, the use of pharmaceuticals may influence the effects of tDCS. In view of the complexity and heterogeneity of MDD -with variations in its etiology, symptoms, course, and response to the treatment -further investigation that aims to refine the knowledge of underlying neurobiology is needed, with the goal to identify circuits and brain areas connected with this pathology.
There is increasing evidence regarding the efficacy of tDCS for the treatment of depression. The first pilot studies of tDCS in depression were conducted over 10 years ago and showed promising results; however, the samples were small. Findings from the first study indicate that tDCS combined with sertraline is more effective than tDCS or sertraline alone.
This suggests that tDCS is less effective on average as a monotherapy than escitalopram and therefore should not be considered a replacement for antidepressant medication. However, tDCS had minimal adverse effects and was more effective than placebo, which allows it to be considered as a treatment in settings where escitalopram or other pharmacological interventions are not recommended, or where there is a patient preference for non-pharmacological treatments.
Novel tDCS protocols should investigate how to optimize parameters to further enhance patient outcomes. Home-based tDCS where the patient or carer is trained to administer tDCS at home, under the remote supervision of clinicians, is currently being developed and has the potential to greatly increase the feasibility and convenience of tDCS treatment.
This procedure requires special equipment certified for remote use and protocols for monitoring progress. Bilateral prefrontal stimulation has been shown to be effective in the treatment of depression.
The current was 2 mA, and session duration was 30 minutes. Increasing efficacy was noted as the number of sessions increased. Other protocols have been tested, but all used anodal stimulation over the dorsolateral prefrontal cortex. Schizophrenia occurs in 0. The clinical symptoms of the disorder can be divided in 3 groups: positive, negative, and cognitive. Positive symptoms are characterized by hallucinations, delusions, thought disorders, and movement disorders.
Negative symptoms involve blunted affect, lethargy, and social withdrawal. A constant, low intensity current is passed through two electrodes placed over the head which modulates neuronal activity. There are two types of stimulation with tDCS: anodal and cathodal stimulation. Anodal stimulation acts to excite neuronal activity while cathodal stimulation inhibits or reduces neuronal activity.
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These might one day complement more established noninvasive medical technologies, such as magnetic stimulation and ultrasound, to influence brain function and behavior. Marom Bikson et al. Her stories about life science technologies have also appeared in Nature magazine.
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