It’s Nioclelis day, with another incredible report from this lab [cite source=’pubmed’]23448946[/cite]. In this case, it’s a brain-to-brain interface (BTBI)–a realtime flow of information from one brain to another. In practical details, it’s not quite as exciting as one might think. One rat (the encoder) makes a decision between two textures of levers. A multi-electrode array records cortical activity related to the choice, codes it as texture 1 or texture 2 and then plays one of 2 patterns into a stimulating array of another rat (the receiver). The receiver rat can then make a behavioral response based on which of the two patterns it has received. As you can see, the heavy lifting here is done by the interface between the two rats. In fact, both rats can do the task independently (and were trained up that way). It’s like having one rat press a button to play one of two sounds, and the other rat has been trained to make responses based on the sound it hears–really it’s just a fancy way of communicating the information between the two. The researchers note changes in response latency when working as a dyad, which they take to indicate a complex interrelationship forming between the rats. I didn’t dig to deeply into the data, but it seems to me that this is just evidence for the task being a bit more difficult/different when working as a true dyad (especially in terms of the timing of the broadcast). It really is impressive, but not quite revolutionary as some press coverage has implied. It also seems to be a missed opportunity–the real chances for inter-brain communication come from true interaction. For example, perhaps amygdala activation from one rat is broadcast to the cortexes of the others, enabling them to know when it is afraid. Delgado once did something like this, where monkeys in a colony could press buttons that could calm or agitate a member in the colony, and they quickly began using these to exert social control over one another! Anyways, this is a cool and fascinating start, but probably just the tip of the iceberg of how direct intra-brain interaction could be used.