A new study from the University of California looks at the link between the bonding hormone oxytocin and the effect of marijuana in social contexts that improve interpersonal bonding. Their findings offer insight into how the hormone could make social interactions more fulfilling and satisfying by enhancing our natural cannabinoid receptors.

The study, titled ”Endocannabinoid signaling mediates oxytocin-driven social reward” has been published in the journal PNAS.

The hormone Oxytocin.
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Oxytocin signals the brain to synthesize anandamide, dubbed the “bliss molecule,” as part of the reward mechanism in the brain — anandamide activates brain receptors that trigger feelings of happiness and motivation. It’s a naturally occurring molecule in the human body, but there’s another substance that links up with these receptors (the endocannabidoid system) with similar results: marijuana‘s THC.

Known as “the body’s own cannabinoid system,” the ECS is involved in a variety of physiological processes including appetite, pain-sensation, mood, memory, and mediates the psihoactive effects of cannabis in the brain. Previous studies have shown that the ECS has a part to play in the regulation of inter-neuron signalling in the nucleus accumbens, the region of the brain that oxytocin acts upon to reward social activities.

When the researchers stimulated the neurons responsible for anandamide production but blocked the effects of the molecule, they found that the effects of oxytocin on this area of the brain were also inhibited — suggesting that anandamide is the vector by which oxytocin strengthens social behavior in the brain.

To test this hypothesis, they administered drugs that prevent anandamide deterioration in mice, that showed increased enjoyment in social activities, spending much more time with other mice than the animals that were treated with a placebo. The team speculates that THC might also have a similar effect on the brain, promoting social interactions and heightening our enjoyment of such activities.

This is the first study to display the effect of oxytocin and marijuana-like neurotransmitters on humans  social interactions. The findings could help scientists delve into the functional mechanisms of oxytocin and allow them to better understand social-impairing conditions such as autism, and even help them develop new treatments to tackle the symptoms of autism.