Washington: Ever wondered why some cannabis users develop an addiction while others don't? Well, recent research has the answer. The study has claimed that a shift from reward-driven use to habit-driven use is what makes the users addicted to cannabis.
The study published in the journal 'Biological Psychiatry: Cognitive Neuroscience and Neuroimaging', used brain imaging to monitor neural activity when cannabis users viewed images associated with cannabis use, referred to as drug cues.
Although all of the cannabis users in the study reported heavy use, only some were dependent on the drug. Both dependent and non-dependent cannabis users had exaggerated responses in a brain region that processes reward – the ventral striatum – compared with people who didn't use cannabis. Interestingly, the dependent users also had larger responses in a brain region that forms habits – the dorsal striatum.
"The present findings reflect that heavy cannabis use is promoted by changes in the brain's reward system--however, these changes alone may not fully explain addictive use. Addictive use may rather be driven by changes in brain systems that promote habitual-- automatic--use, which may also explain the fact that addicts continue to use despite a lack of experiencing rewarding effects of the drug. As such, their behaviour has become under the control of the drug cues, rather than the actual reward expectation," said study author Benjamin Becker.
Dependent users also had increased responses in other regions throughout the brain, including regions that attribute importance to things, for example, drug cues. This suggested that the development of cannabis addiction incorporates additional brain regions that may strengthen a person's desire to seek the drug.
"These findings are important insights that can help us better understand why some individuals might be more likely to become addicted to cannabis," said Cameron Carter, Editor of Biological Psychiatry: Cognitive Neuroscience and Neuroimaging.
Differentiating the unique brain circuits behind dependent cannabis use could also be useful for understanding how to combat the problem of cannabis addiction.
"The identification of the dorsal striatum and habitual behaviour as a driver of addiction may allow the development of more specific treatment approaches to increase treatment success," said Xinqi Zhou, first author of the study....