Evidence-based Umbrella Review of Cognitive Effects of Prefrontal tDCS.
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation approach which has been increasingly used as an investigational tool in neuroscience. In social and affective neuroscience research, the prefrontal cortex has been primarily targeted, since this brain region is critically involved in complex psychobiological processes subserving both ‘hot’ and ‘cold’ domains. Although several studies have suggested that prefrontal tDCS can enhance neuropsychological outcomes, meta-analyses have reported conflicting results. Therefore, we aimed to assess the available evidence by performing an umbrella review (UR). We evaluated the effects of prefrontal active vs. sham tDCS on different domains of cognition among healthy and neuropsychiatric individuals. AMSTAR-2 was employed to evaluate the quality of systematic reviews and meta-analyses and the GRADE system was employed to grade the quality of evidence. PubMed/MEDLINE, PsychINFO and the Cochrane Database of Systematic Reviews were searched, and 11 meta-analyses were included resulting in 55 comparisons. Only 16 comparisons reported significant effects favoring tDCS, but 13 of them had either a very low or low quality of evidence. Systematic reviews were rated as having critically low and low quality. Among several reasons to explain these findings, the lack of consensus and reproducibility in tDCS research is discussed.
PMID: 32577732 [PubMed – as supplied by publisher]
Soc Cogn Affect Neurosci. 2020 Jun 24;:
Authors: Farhat LC, Carvalho AF, Solmi M, Brunoni AR