Researchers at the University of Washington's (UW) Institute for Learning and Brain Sciences have conducted a study to show that two brains can be directly linked to each other, allowing one to communicate with the other by sending signals.

Andrea Stocco, a researcher at UW, said that participants transferred their visual experiences to each other in the experiment, which is believed to be the most comprehensive one on brain-to-brain communication.

Researchers used the popular guessing game "20 Questions" in which one participant thinks of an object, while the other tries to guess it by asking yes or no questions.

The participants played the game on the Internet. Ten volunteers were separated into two groups and placed in dark sections of two different laboratories, which are 2 kilometers from each other. While playing the game, they were normally required to ask questions to guess the object. One group wore an electrode-studded cap connected to an electroencephalography (EEG) machine that recorded brain activity and sent a response to a second participant. The others wore a cap with a magnetic coil positioned over the part of the brain that controls the visual cortex. While one participant saw an object on a screen, the other wearing the electric coil used a mouse to select from a list of questions to get more information about the object. The first participant wearing the electrode cap signaled the answer to the questioner by looking at a flashing light indicating the answer as "yes" or "no." During the experiment, subjects knew the correct answer in the 20 Questions game, 72 percent of the time.

One of the researchers, Chantel Prat, said that participants interpreted the object that they saw through brain signals and communicated it to each other. She said it was the first time they have seen this. The study was published in the journal PLOS ONE.