That's what happens to a shy octopus on ecstasy

If you give an Octopus MDMA, it will become delicate and you want to get involved.

What looks like the premise of a children's book at Burning Man is actually the conclusion of a study published Thursday in the journal Current Biology. Neuroscientist Gül Dölen, who is studying social behavior at the Johns Hopkins University School of Medicine, and Eric Edsinger, a researcher at the Woods Hole Marine Biology Laboratory, Massachusetts, observed the result.

Most humans like to hang on their buds. We share this trait with animals like dogs, but not with the two-point octopus in California. Octopus bimaculoids is an asocial creature, which means it avoids other octopuses whenever possible. Put it in a tank with another octopus and it could become aggressive or pack tightly against a wall.

There is just one exception – during mating, this antisocial behavior stops. Dölen thought that a neuromechanism was at stake and wondered if MDMA (3-4-methylenedioxymethamphetamine, better known as ecstasy) could trigger this mechanism to turn the cephalopod into a more social animal.

This was not surprising for himself. "The search for psychedelic drugs as possible treatments has been reborn," she said.

Robert C. Malenka, professor of psychiatry and neuroscience at Stanford University, who did not participate in this study, called for further study of MDMA in an influential paper published in 2016. The MDMA, despite its taboo associations with the classified as Schedule 1, reserved for illicit drugs with high potential for abuse – is under study as a therapy for veterans of the army suffering from PTSD.

Some people call MDMA "an empathogen" because "it reduces inhibition, reduces social anxiety, reduces the fear of social interaction," Malenka said. And because MDMA can reduce hostility and anger, Malenka sees its value as a tool in neuroscience. "I passionately believe that we need to understand" what makes positive social interactions, he said – it does not take less than the "survival of our species".

Enter other species. There is a long and sometimes dubious history of scientists administering animals with psychoactive drugs. Tests conducted in the 1950s showed that spiders create chaotic networks when they are drugged with caffeine or mescaline. In 1962, during an experiment that went terribly wrong, scientists from the University of Oklahoma injected a considerable amount of LSD to an elephant named Tusko.

Toxicity tests funded by the National Institutes of Health and the Department of Defense have exposed high doses of MDMA to rabbits, monkeys and rodents, said neuropharmacologist Allison A. Feduccia in an organization based in Santa Cruz, California. California. Studies or MAPS. MAPS donated the MDMA used in this study. The doses received by the octopuses were much more related to what a human would take, she said. (This is also, to the knowledge of Feduccia, the first time the substance was given to an octopus.)

In experimental trials, the authors placed an octopus for 30 minutes in a three-chamber tank, installed as a house with separate rooms. The center piece was empty. In the room on the left was a perforated container containing "Star Wars" figures (a Chewbacca or Stormtrooper toy). In the right wing, a bright overturned flowerpot contained another octopus. This flowerpot container had holes, so octopus could communicate by sight, touch and chemically, but antisocial animals could not hurt themselves.

The sober octopuses spent most of their time away from the other animal – they rushed into the room with the "Star Wars" figurines. But the study authors then dissolved MDMA in the seawater and bathed the octopus in the liquid for 10 minutes. They placed the drugged octopuses, male and female, in the central chamber. And these octopuses spent a lot more time, on average 15 minutes, in the room with another male octopus.

The MDMA octopus seemed to be "floating and relaxed, squeezing the flowerpot" that contained the other octopus, said Dölen.

"In terms of the behavioral characteristics, the octopuses being more prosocial, they support what we see therapeutically," said Feduccia, author of a pilot trial of MDMA-assisted psychotherapy for autistic adults.

The authors observed an even stranger behavior than they did not report in the study, Edsinger said. He was reluctant, even after a long interrogation, to describe in more detail what the octopus was doing, because scientists could not know if MDMA had induced these actions.

"They show that MDMA is increasing a particular type of social behavior in octopuses, namely the social approach and the investigation of unknown male octopuses," said Gillinder Bedi, a researcher at the University of California. Melbourne in Australia, who was not involved in this work. "It's a bit difficult to call it" prosociality, "but it seems to be at least a social interest." Studies have shown that other lab animals exposed to MDMA are also becoming more socially active.

MDMA binds to a receptor of the serotonin molecule, a neurotransmitter that affects our mood. The receptor is kind of like a vacuum at the end of a neuron that sucks up the serotonin molecules, Malenka said. The MDMA pumps the pump from a vacuum cleaner to a leaf blower, releasing more serotonin.

Octopus brains are organized totally differently from ours or rodents. Animals just have a fraction of the neurons we make. Lacking cortex, their brain is more like a snail than yours or mine. "Octopuses are special because they are separated from humans by more than 500 million years of evolution, but they are capable of making as many complex and interesting cognitive behaviors," Dölen said.

They also seem to have something in their brain like the serotonin receptor in humans. Edsinger was part of the team that sequenced the two-point octopus genome in California in 2015. "If we look at the part of the gene that encodes the receptor binding pocket – it's very similar," Edsinger said. .

Given the stifling behavior and a similar part of the gene, the authors state that "the neural mechanisms that underlie social behaviors exist in Bimaculoides. In other words, despite the 500 million years of separation between humans and octopuses and our very different brains, what rewards us for social activity probably also rewards octopuses.

Malenka, who described the approach in this report as "very intelligent," said that he was not completely convinced that serotonin and its receptors explained this behavior. Genetic evidence is suggestive, but MDMA also interacts with neurotransmitters like dopamine, he said.

"Without a test like blocking serotonin and then testing the effects of MDMA, you can not be sure it's the mechanism," Bedi said. "However, I think it's not an unreasonable assumption."

Dölen said that she would like to do more tests with more animals, like giving MDMA to an octopus at the same time as Prozac or a selective serotonin reuptake inhibitor that binds to the same animal. receiver. And Edsinger said he planned to sequence two closely related octopus genomes – one species trailing in groups, the other being a band of solitaries – to look for the source of social differences in their genes.

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