Octopuses are notoriously asocial, preferring to be alone and even growing hostile in the presence of other octopuses. But when researchers gave them the party drug MDMA, also known as ecstasy, they became downright cuddly.
While the brains and nervous systems humans and octopuses are different in many ways, they seem to share an ancient commonality in the way their brains handle serotonin, a chemical that regulates mood and social behaviors. MDMA acts by releasing more serotonin in the brain.
A study, published in Current Biology and conducted by Johns Hopkins University and the Marine Biological Laboratory, involved an experiment that placed a hand-sized octopus in the center chamber of a three-chambered tank. In one side chamber was a colorful inanimate object, like a Star Wars Chewbacca or Stormtrooper figurine, and in the other was another octopus, protected inside a small cage from a possible attack.
When undosed, octopuses spent more time with the figurine. But when a mild dose of MDMA was added to a bath, they showed more interest in the other octopus, even hugging with several arms the container that the second octopus was placed in.
The idea of the study came after Johns Hopkins neuroscientist Gül Dölen noticed that the sequenced octopus genome included the same genes for a protein that can binds serotonin to brain cells.
“After MDMA, they were essentially hugging,” Dolen told NPR, adding that the dosed octopuses were “really just much more relaxed in posture, and using a lot more of their body to interact with the other octopus.”