Two rats can be connected by arrays of microelectrodes inserted into the area of the cortex that processes motor information to work together on a task. Their coordination is about 70% efficient based on 2,000 connected brain cells.
... the decoder's brain began to represent in its tactile cortex not only its own whiskers, but the encoder rat's whiskers, too. We detected cortical neurons that responded to both sets of whiskers, which means that the rat created a second representation of a second body on top of its own."
... in this case, we are not inputting instructions, but rather only a signal that represents a decision made by the encoder, which is transmitted to the decoder's brain which has to figure out how to solve the puzzle. So, we are creating a single central nervous system made up of two rat brains,"...
To test the transmission limits of the brain-to-brain communication, the researchers placed an encoder rat in Brazil, at the Edmond and Lily Safra International Institute of Neuroscience of Natal (ELS-IINN), and transmitted its brain signals over the Internet to a decoder rat in Durham, N.C. They found that the two rats could still work together on the tactile discrimination task.
"So, even though the animals were on different continents, with the resulting noisy transmission and signal delays, they could still communicate," said Miguel Pais-Vieira, PhD, a postdoctoral fellow and first author of the study. "This tells us that it could be possible to create a workable, network of animal brains distributed in many different locations."