Some habits die hard. Like humans zapping their brains. We did this back in Ancient Greece, when medics used electric fish to treat headaches and other ailments. Today we’re still at it, as neuroscientists apply electric currents to people’s brains to boost their mental function, treat depression, or give them lucid dreams.

During the eighteenth century our understanding of electricity was growing apace, and the use of electricity to treat a range of physical and mental ailments, known as electrotherapy, was incredibly popular.

In 1802, [Giovanni] Aldini zapped the brain of a decapitated criminal by placing a metal wire into each ear and then flicking the switch on the attached rudimentary battery.

“I initially observed strong contractions in all the muscles of the face, which were contorted so irregularly that they imitated the most hideous grimaces”, he wrote.

Via Wired.