Alien Hand Syndrome

In 2011, a woman named Karen underwent surgery to treat her epilepsy. The procedure involved cutting the corpus callosum, a band of fibers which connect the left and right sides of the brain. 

Surgery cured Karen of her epilepsy, but it caused an entirely different problem – Alien Hand Syndrome. 

After the two sides of Karen's brain were disconnected, the left and right hemispheres were in a constant struggle for control, but she was only conscious of behaviors of one side.

Before doctors found a solution, her hand had a mind of its own – undressing her blouse at inappropriate times, taking things out of her purse and leaving them at random locations. The hand even attacked her – Karen would unwillingly punch and slap herself in the face.