When it comes to self-improvement, there’s no shortage of books, tips, websites and online articles, particularly when it comes to boosting memory or brain power. The search term “hack your brain” turns up more than 7 million hits on Google. In this episode, we’re talking about brain stimulation – using external devices involving magnetic fields and electricity to zap the brain. In recent years, a market of do-it-yourself devices has developed, promising products that can deliver a – quote unquote – “instant boost” to memory or attention. But the safety of these devices is another question, as is whether they even work.