The psychoactive drug known as ecstasy can make people feel extra loving toward others. A study published Thursday suggests it has the same effect on octopuses. Octopuses are almost entirely antisocial, except when they're mating. Scientists who study them have to house them separately so they don't kill or eat each other. However, octopuses given the drug known as MDMA (or ecstasy, E, Molly or a number of other slang terms) wanted to spend more time close to other octopuses and even hugged them. Octopuses' ... brains have a host of strange structures that evolved on a completely different trajectory from the human path. "They have this huge complex brain that ... has absolutely no business acting like ours does - but here they show that it does," says [neuroscientist Judit] Pungor. "This ... gentle, cuddly behavior is really pretty fascinating." The idea to test the drug's effect in octopuses came from Gul Dolen, a neuroscientist at Johns Hopkins University. "My lab has been studying MDMA for a long time, she says, "and we have worked out a lot of neural mechanisms that enable MDMA to have ... pro-social effects." Dolen got interested in octopuses a few years ago, when scientists sequenced the full genetic code of a ... California two-spot octopus. It turns out that octopuses and people have almost identical genes for a protein that binds the signaling molecule serotonin to brain cells. This protein is also the target of MDMA, so Dolen wondered how the drug would affect this usually unfriendly animal.