Hooked on Love: Oxytocin Possible Solution for Drug Addiction

Hooked on Love: Oxytocin Possible Solution for Drug Addiction

Chinese researchers have compared brain scans of lovers and drug addicts, and discovered a defining difference: oxytocin. Based on its ability to reverse addiction-like behaviour in lovers, it is a possible solution to resolving the age-old problem of drug addiction.

Written by: Micaela Leong

Some may say love is just another drug, and they would not be far from the truth. Researchers from the Chinese Academy of Sciences in Hefei, China, studied the neurological similarities and differences between romantic love and drug addiction. Their findings showed that new couples shared some common brain activity patterns with drug addicts - but the surprising discovery, was that addiction-like characteristics in lovers gradually disappeared as the relationship progressed. Researchers sought to answer the question: if “love addiction” can be reversed, can drug addiction be reversed too?

Only Fools Rush In

On the surface, lovebirds and drug addicts exhibit similar behaviour and emotions. Couples within the first six months of their relationship were observed to experience euphoria, obsess over their partner, and develop a strong emotional dependency on them. Similarly, drug addicts experience drug-fueled highs, and exhibit intense drug-seeking and compulsive behaviour. After breakups, ex-couples display lethargy, anxiety, and chronic loneliness - common drug withdrawal symptoms.

Chinese researchers placed couples and drug addicts in an fMRI (functional Magnetic Resonance Imaging) machine. They showed couples pictures of their significant other, while addicts were shown drug-related cues. When comparing brain scans, both groups showed activity in brain regions involved in the brain’s reward pathway. This pathway allows the brain to associate an external stimulus with pleasurable, positive emotions, when dopamine connects the reward and pleasure centers of the brain. If you met someone (external stimulus) and had pleasant, enjoyable experiences with them (reward), you desire see them again to feel that euphoria. Similarly, drugs (external stimulus) get you high (reward). The promise of reward drives you to take drugs, thus fueling addiction.

However, as time progressed for both couples and addicts, a stark difference appeared. From the brain scans, the longer a couple were together, the greater the activation of brain regions involved in cognitive control and social cognition. These regions are involved in impulse control, and social interactions. At a resting state, long-term couples had increased connectivity within the social cognition network. At this stage, their relationship was built on mutual connection, instead of feel-good emotions from the reward pathway, hence reversing “love addiction”.

In contrast, the detrimental effects of drug-taking intensified, resulting in relapse, poor cognitive control, and reclusiveness. For drug addicts, the resting-state connections between the reward circuit and motivation circuit increased, meaning the desire to take drugs to feel good again intensified. Connections within the control circuit also decreased, indicating poor self-control and increased chance of relapse.

We Have Chemistry

Oxytocin, affectionately known as the “cuddle” hormone, is the neurotransmitter that could explain the difference between long-term lovers and drug addicts. Lovers have increased production of oxytocin, hence strengthening their relationship, and reducing addiction-like behaviour. Addicts, however, are unable to produce oxytocin.

Unknown to most, oxytocin also serves an inhibitory purpose. When relationships or drug use are cut short, oxytocin prevents people from returning to their exes or relapsing. Unfortunately, repeated drug abuse physically alters brain cells, rendering the oxytocin system to work less efficiently. With insufficient oxytocin, addicts are at greater risk of relapsing. Meanwhile, the dopamine receptors in the reward pathway also physically change to intensify drug-seeking behaviour. Stopping drug abuse becomes increasingly difficult.  Despite challenges, hope is not lost.

Experiments done on cocaine-tolerant rats showed that when oxytocin was administered, their tolerance for cocaine reduced, and produced similar results of normal, non-tolerant rats. Brain activity in regions associated with social and cognitive control also increased. With improved control, compulsive behaviour can reduce, and likelihood of relapse could decrease. These findings prove that external administration of oxytocin may not only reverse addiction, but possibly end it for good.

Overall, oxytocin reduces compulsive drug-seeking and risk of relapse - the biggest obstacles to treating drug addiction. Its potential ability to stop addiction has been demonstrated on two accounts: self-produced oxytocin reduces addiction-like qualities in lovers, and rats externally administered oxytocin can bring tolerance down to pre-abuse levels. Its mechanism is not fully understood yet, but the Chinese researchers speculate that it allows addicts to be less drug-dependent, by decreasing stress and anxiety, and facilitating social interactions. Cognitive control is also regained, giving self-control back to addicts. Despite there being no clinical trials to prove its ability to reverse drug addiction in humans, this research is a hopeful indication, and a good omen to saving drug addicts from a vicious cycle.

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References:

Zou, Z., Song, H., Zhang, Y., & Zhang, X. (2016, September 22). Romantic Love vs. Drug Addiction May Inspire a New Treatment for Addiction. Retrieved February 28, 2017, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5031705/

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First written assignment for SP 1541: Exploring Science Communication Through Popular Science.