Transcranial direct current stimulation applied to schizophrenia: state of knowledge

1Gisly Macedo de Sousa; 1Maria Isabele Ferreira; 1Gabrielly Oliveira Silva; 1Ana Lúcia Trindade Martins; 1Leiliane Nascimento Nunes; 1Paloma Cavalcante Bezerra de Medeiros

1Universidade Federal do Piauí

OBJECTIVE: Synthesize the state of knowledge about the application of Transcranial Direct Current Stimulation (TDCS) in schizophrenia.

METHODS: Based on PRISMA recommendations, a survey of systematic reviews indexed in seven databases was carried out: Cochrane, Lilacs, PsycInfo, Pepsic, Scielo, PubMed Central (PMC), Scorpus, Springer Link and Web of Science, following five criteria of eligibility, with the descriptors: “transcranial direct current stimulation AND schizophrenia”. Nine articles, published from 2014 to 2019, were selected to compose the review.

RESULTS: The results are ambiguous, with studies that  positively corroborate with the technique and those that indicate the non-significant effect of the instrument in reducing symptoms. Overall, the analysis highlights the TDCS as a promising instrument to reduce the severity of hallucinations, the negative symptoms and improving neurocognition. However, It has not yet been possible to assert its effectiveness in general and positive symptoms and in social functioning.

CONCLUSIONS: This review points out to the existing gaps and instructions for future research and indicates that studies with larger samples are needed, so that it can point out more evidence.

KEYWORDS: Neuromodulation; Schizophrenia; Symptoms