Primum non nocere or primum facere meliorem? Hacking the brain in the 21st century

Neuroethics of Neuromodulation: An Update

This article reviews neuroethics issues that arise with the development, translation, and use of technologies for neuromodulation. Three electronic databases (PubMed, Embase, and PhilPapers) were searched for relevant articles published between 1/1/16 - 6/26/18. We focus on pressing ethical issues related to the use of deep brain stimulation (DBS), adaptive DBS (aDBS), transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and associated technologies. The neuroethics issues we address include privacy, continued access to devices, device removal, do-it-yourself neurostimulation, neuroenhancement, media coverage, changes in personal identity and agency, informed consent, and neuromodulation in minors. This review should be of assistance to a variety of stakeholders, including neurotechnology developers, as they make important decisions that will drive these neurotechnologies.

Transcranial Direct Current Stimulation in the Acute Depressive Episode: A Systematic Review of Current Knowledge

Major depressive disorder is a severe, refractory mental disorder. Only one third of patients treated with antidepressants achieve remission after 3 trials, while subject to adverse effects. Therefore, the investigation of alternative treatments is paramount. The aim of this systematic review was to summarize the most recent evidence of transcranial direct current stimulation (tDCS) intervention for the acute phase of major depressive disorder. A PubMed search was performed including the terms "transcranial direct current stimulation" OR "transcranial direct stimulation" OR "tDCS" AND "major depressive disorder" OR "major depression" OR "depression" AND "trial." The search was conducted from inception until February 2018. Our search yielded initially 165 results, and 14 randomized clinical trials were included according to eligibility criteria. Most studies were pilot studies, with mixed findings. Two large randomized clinical trials recently published also presented primary negative findings. Study protocols usually used anodal left/cathodal right dorsolateral prefrontal cortex stimulation, 1 to 2.5 mA, and 5 to 20 tDCS sessions. We discuss the limitations of the included trials, such as sample and tDCS parameters heterogeneity between studies. To conclude, tDCS seems to be safe and devoid of serious adverse effects, although robust efficacy has not been consistently demonstrated in clinical trials assessing an acute treatment course of up to 4 weeks. Further directions are discussed, such as parameter individualization, investigation of biological markers, and home-use tDCS.