Creating a "superbrain" of connected minds, scientists say they have enabled a rat to help a fellow rodent while the animals were a continent apart but connected through brain electrodes.
With electrodes imbedded in its cortex, a rat in a research institute in Natal, Brazil sent signals via the internet to a counterpart at a university lab in Durham, North Carolina, helping the second animal to get a reward.
The exploit opens up the prospect of linking brains among animals to create an "organic computer", said Brazilian neurobiologist Miguel Nicolelis.
It also helps the quest to empower patients stricken with paralysis or locked-in syndrome, he said.
"We established a functional linkage between two brains. We created a superbrain that comprises two brains," Nicolelis said in a phone interview with AFP.
Published in the journal Scientific Reports, Nicolelis' team gave basic training to thirsty rats, who had to recognise lights and operate a lever to get a reward of water.
They then implanted ultra-fine electrodes in the rats' brains, which were linked by a slender overhead cable to a computer.
In a glass tank in Natal, the first rat was the "encoder", its brain sending out a stream of electrical pulses as it figured out the tricks for getting the reward.
The pulses were sent in real time into the cortex of the second rat, or "decoder", which was facing identical apparatus in a tank in North Carolina.
With these prompts from its chum, the decoder rat swiftly found the reward in turn.
This "suggests we could create a brain net, formed of joined-up brains, all interacting", the scientist said, hastening to stress that such experiments would only be conducted on lab animals, not humans.