Transcranial electrical brain stimulation methods for treatment of negative symptoms in schizophrenia

Abstract

In recent years noninvasive brain stimulation (NIBS) applications have emerged as a third and novel treatment option alongside psychopharmacology and psychotherapy in the treatment of mental diseases. It is assumed that NIBS could represent a supplement or (in some indications) even replacement to established therapeutic strategies, e.g. in disorders with high resistance to current treatment regimens, such as negative symptoms or cognitive impairments in schizophrenia. Although positive symptoms in schizophrenia can be treated sufficiently with antipsychotic drugs, patients with negative symptoms frequently suffer from persistent lack of impetus, cognitive decline, social withdrawal and loss of global functioning in the activities of daily life; however, in these cases, current treatment strategies exert only moderate effects, and new treatment options are urgently needed. This review article provides a summary of the clinical effects of new electrical NIBS methods, e.g. transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), and transcranial random noise stimulation (tRNS) for the treatment of negative symptoms in schizophrenia. These new NIBS methods could help restore the disrupted neuronal networks and improve disturbed connectivity, especially of the left dorsolateral prefrontal cortex and left temporoparietal junction. Promising results are reported for the treatment of negative symptoms with tDCS, tACS and tRNS and could thus represent new therapeutic options in the treatment of schizophrenia.