Changes in motor cortical excitability in schizophrenia following transcranial direct current stimulation

Gordon, Pedro Caldana; Lane Valiengo, Leandro da Costa; Rodrigues de Paula, Vanessa Jesus; Galhardoni, Ricardo; Ziemann, Ulf; de Andrade, Daniel Ciampi and Brunoni, Andre Russowsky (2019): Changes in motor cortical excitability in schizophrenia following transcranial direct current stimulation. In: Progress in Neuro-Psychopharmacology & Biological Psychiatry, Vol. 90: pp. 43-48

Abstract

Schizophrenia is a disorder associated with cortical inhibition deficits. Transcranial direct current stimulation (tDCS) induces changes in cortical excitability in healthy subjects and individuals with neuropsychiatric disorders depending on the stimulation parameters. Our aim was to investigate whether a previously published tDCS protocol associated with symptomatic improvement in schizophrenia would induce changes in motor cortical excitability, assessed by transcranial magnetic stimulation paradigms, i.e., short-interval intracortical inhibition (SICI) and intra-cortical facilitation (ICF). We assessed cortical excitability measurements in 48 subjects with schizophrenia before and after a single session of active tDCS (20 min, 2 mA, anode over left dorsolateral prefrontal cortex, cathode over left temporoparietal cortex) or sham. Those who received active tDCS had a significant increase of SICI in the left motor cortex compared to those who received sham stimulation (Cohen's d = 0.54, p = .019). No changes were observed for ICF. In addition, lower SICI was associated with higher age (beta = -0.448, p < .01). Increase in intracortical inhibition may indicate a mechanism of action of tDCS in this population. Future studies should investigate whether this finding is a biomarker of treatment response for schizophrenia.

• Item Type: Journal article
• Faculties: Medicine
• Subjects: 600 Technology > 610 Medicine and health
• ISSN: 0278-5846
• Language: English