Mega study examines brain stimulation's effect on memory and focus.

A meta-analysis of over 100 studies on transcranial electrical stimulation (TES) has concluded that the technique, which applies an oscillating current to the brain, brings about moderate improvements in attention, long-term memory, working memory, the ability to process new information and solve problems, and other high-level cognitive processes. However, some researchers have questioned the efficacy of TES, saying that the studies included in the meta-analysis differed vastly from one another in terms of which parts of the brain were targeted, the arrangement of the electrodes on the scalp and the frequency and intensity of the electrical current.