Researchers at Duke University have created the first ever brain-to-brain interface, allowing rats to send sensory and motor information to one another.

In a previous study, the team inserted electrodes into areas of the brain that processed tactile information, and these electrodes were then attached to infrared sensors. This allowed the rats to “feel” infrared sensors.

Next, the researchers attached electrodes from one rat brain to another. The experiment consisted of two rats in separate cages. One rat was denoted as the “encoder” and the other as the “decoder.” Both rats were taught to press on a lever once an indicator light turned on for a reward.

When the encoder rat pressed on the lever in response to an indicator light, an electrical signal was created in the encoder rat’s brain and sent to the decoder rat’s brain via the electrodes. There was no visual stimulus in the decoder rat’s cage to indicate which lever to press; the decoder rat used the electrical signal sent from the encoder rat to decide. If the decoder rat achieved the task, it received a reward, while the encoder rat received an extra reward.

Failure of the decoder rat to press the correct lever led to the denial of the encoder rat’s extra reward. Therefore, the encoder rat learned to send clearer brain signals the next time around.

Although this process occurs instantaneously, it took over a month of daily hour-long training for the decoder rats to be able to learn the information.

Another successful study linked a rat at Duke University to another rat in a laboratory in Brazil, showing promise for future brain interaction procedures.

—Stephan Jayaratnam

With files from the BBC