Ecstasy experiment reveals octopuses' similarity to humans
- by Laura Grandis
- in Médecine
- — Sep 22, 2018
For those who have ever wondered what happens when you get sea creatures hooked on drugs, USA scientists have found the answer. Scientists in the USA have just lived that dream.
Octopuses are nearly entirely antisocial, except when they're mating, and scientists who study them have to house them separately so they don't kill or eat each other.
Scientists have studied how ecstasy affects the California two spotted octopus Octopus bimaculoides, which is known for its aggressive behavior in all organisms including their relatives.
Octopuses' closest relatives are molluscs such as snails and slugs, and their brains have a host of unusual structures that evolved on a completely different trajectory from the human path.
The genetic analysis of the California two-spot octopus revealed that its brain had the molecular components required to sense MDMA.
In particular, the transporter that binds the neurotransmitter serotonin is almost identical between humans and O. bimaculoides. Serotonin is responsible for mood regulation.
MDMA, has always been known as a party drug that inspires a sense of euphoria and empathy along with a desire to dance all night. Dolen said humans on MDMA also touch each other more frequently when on MDMA.
Humans, rats, and mice are pretty social animals. While humans are naturally social creatures, octopuses prefer a solitary existence and rarely socialise, with the exception of mating. The researchers ran two experiments. They placed the drugged octopuses, males and females, back into the central chamber. On one side, visible through a clear wall with a hole so the octopus could enter, was a novel object - a plastic action figure. If successful, octopuses may become a new laboratory model for the human brain. They ignored or avoided contact with the other octopus and just kind of sat around being all squishy and stuff. "They were just taking these postures of super hypervigilance".
For the MDMA experiment, four male and four female octopuses were exposed to the drug, before being put in the experimental chamber for 30 minutes.
"It's not just quantitatively more time, but qualitative", Dölen said in a statement. They hugged the cages and placed their mouth parts over the cages, she explained.
When people take MDMA, the drug popularly known as ecstasy, a rush of serotonin, dopamine, and oxytocin produces feelings of emotional closeness and euphoria, making people more interested than they would normally be in connecting and sharing with other people.
"The brains of octopuses are more similar to those of snails than humans, but our studies add to evidence that they can exhibit some of the same behaviours that we can".
First, though, the results will need to be affirmed through further experiments.
THE DANCE drug ecstasy makes people feel loved-up and touchy-feely, and a new study suggests it has the same effect on octopuses. Prof de Wit said that would help rule out the idea that they were friendlier the second time because they'd got used to the tank, or the other octopus.