WTF?! A team of researchers has been testing the ability to control brains using just light. They can control the actions and emotions of lab mice in a process they say is entirely reversible. There is no word on whether this could work on humans.

The researchers describe a method that uses a special kind of blue light to control communication between neurons in the brain. It temporarily stops communication between specific brain cells. The researchers can control behavior and emotions depending on which brain areas they target. In one example, they removed a mouse's fear memory.

Called Opto-vTrap, the method was developed in South Korea by Director C. Justin Lee from the Center for Cognition and Sociality within the Institute for Basic Science and professor Heo Won Do from Korea Advanced Institute of Science and Technology. The researchers are using it to understand better how the brain works. Lee says it can eventually help improve epilepsy treatment, muscle spasm treatment, and skin tissue expansion.

There are existing ways of controlling brain activity, but they may not affect certain cell types. These alternative methods can also make neurons misfire or cause long-lasting or permanent damage to neurons. Conversely, the effects of Opto-vTrap wear off after around 15 minutes.