Stimulating the brain with electricity improves working memory, mental maths,focused attention, creativity and could help treat depression. You can even buy DIY kits online. That’s the good news. The bad news is that the most recent investigation has found it has almost no measurable effect on the brain.
It’s a conclusion that is likely to be controversial. Over the past decade, thousands of studies have reported a beneficial effect of transcranial direct current stimulation (tDCS) on the brain, as well as on behaviour and cognition – so much so that it has become something of a hot topic in neuroscience.
The idea behind tDCS is that passing a weak current through the brain changes the electrical potential of nerve cell membranes. This alters the strength of connections between neurons, making the circuit more, or less likely to fire. It’s a tricky thing to measure directly, so any physiological effect is inferred by blood flow changes on functional MRI scans, changes in brainwaves measured by EEG, or in the strength of muscle contraction when the motor cortex is stimulated, known as an MEP.
But when Jared Horvath and his colleagues at the University of Melbourne in Australia, pooled the results of more than 100 studies reporting any or all of these measures, they found that only one was convincingly changed after tDCS. The other two were inconsistent at best.
Read full original article: Has the brain-zap backlash begun?