What an Octopus on Ecstasy Can Teach Us About the Brain on Drugs
You may have missed a big discovery a few weeks back concerning researchers that put octopuses on the drug ecstasy. While this sounds like a bad experiment from the LSD-fueled universities of the ’60s, it actually revealed an important brain discovery. Let me explain.
How Serotonin Works
Perhaps most well known for its connection to the feeling of happiness and pleasure, serotonin (5-hydroxytryptamine, or 5-HT) is a neurotransmitter that is involved in a wide variety of brain and body functions. These include the sleep cycle, control of body temperature, appetite, and much, much more.
Low levels of serotonin are associated with depression, and SSRI drugs (drugs that treat depression [e.g., Prozac, Zoloft, etc.]) work by blocking the reuptake process, leaving more serotonin available for use. This new study, however, tried to determine if serotonin’s effect on mood is a genetic one (centered in serotonin transporter molecules) rather than a hormonal one (centered in the serotonin transmission pathways).
In an effort to better understand the effects of serotonin, researchers studied how MDMA (the drug is commonly known as ecstasy or “X”) impacts serotonin in the octopus brain. Why the octopus and why ecstasy? The genetic makeup of an octopus makes it a naturally antisocial creature, and ecstasy is well known as a happiness-inducing drug that makes its users rather touchy-feely and social.
However, the big reason the researchers chose an octopus is that its brain is as different from ours as any alien’s from outer space could be. For example, there are no pleasure centers or reward pathways. Meaning, everything we know about an octopus brain should predict that it would have no response to any drugs that cause an effect in humans.
Octopuses on X Seek Love?
The nervous system of an octopus is decentralized—there is a brain, but each arm has its own control center—so it’s much different from the centralized nervous system of a human, which has one control center, the brain. However, the octopus has genetic coding similar to a human for the serotonin transporter molecules in the brain.
Remember that serotonin in humans impacts the brain at the nerve-to-nerve transmission level but can also be secreted hormonally. It’s this last part that has been believed as the main mechanism of action of many drugs. That they cause more serotonin to be secreted into specific neural pathways that then impact behavior. So if we put octopuses, which have a completely different brain setup on X, they should have no response, because they don’t share the same brain wiring as humans or most mammals.
In the new study, after being bathed in MDMA, the octopuses’ behavior stunned the scientists. These antisocial creatures began touching other octopuses in a gentle, exploratory manner. Basically, they looked like millennials tripping on X at Burning Man.
Given this finding, there was only one conclusion that could be drawn, X acts at a genetic level to change serotonin levels and transporters. Meaning that manipulating serotonin transmission pathways with SSRIs may not be the ideal way to treat depression and other social behavior issues. Instead, the focus of drug discovery for depression may now shift to manipulating gene expression.
The upshot? This is a really freaky study that taught us something completely new about the brain. In fact, if these findings continue to be supported by other studies, these researchers may make it into some college kid’s neuroscience textbook one day and may have changed a generation of new drug discovery. As a result, we may see drugs for depression that focus more on our genes than our neural pathways!