How does addiction affect the brain?
Addiction affects the brain by hijacking the reward pathways and flooding them with dopamine, the “feel good” neurotransmitter. Substances like opioids bind to opioid receptors in areas like the amygdala and nucleus accumbens, overstimulating the dopamine system over time and forming dependency. This drives compulsive drug-seeking behavior despite negative consequences. Addiction also impacts the prefrontal cortex, affecting self-control and decision-making processes.
How long does it take to rewire your brain?
The timeline for brain recovery and “rewiring” neural connections after addiction depends on many factors – genetics, age of exposure, substance used, and length of use all play a role. Generally, experts believe it takes a bare minimum of months to years for the brain to functionally heal after substance dependence. Detox clears drugs from the body, typically in a matter of days or weeks, but rewiring the brain is a longer process.
What part of the brain is targeted by addictive drugs?
The mesolimbic pathway, called the “reward circuit”, is often most directly targeted by addictive drugs. This pathway connects areas like the ventral tegmental area, nucleus accumbens, amygdala, and prefrontal cortex using dopamine signals. An influx of dopamine creates euphoric highs that reinforce addictive behaviors over time.
Do we have opioid receptors in the brain?
The human brain contains an abundance of opioid receptors, especially mu-opioid receptors that mediate pain, reward, and addiction pathways. Substances like heroin and prescription opioids activate these mu-receptors, initiating cascades of dopamine and effects downstream.
Which hormone is responsible for addiction?
Dopamine plays a central role in addiction by signaling pleasure, learning, and reinforcement of compulsive behaviors in the brain. Other neurotransmitters like glutamate and GABA also play roles. Chronic substance abuse can deregulate these chemical messengers.
How does addiction affect the developing brain?
Addiction during youth can severely disrupt healthy brain development, with impacts on maturation that last into adulthood. Structural changes are more severe when addiction occurs at a younger age since neural connections are still actively forming. Addiction changes these patterns, affecting learning, cognitive skills, emotional regulation, and impulse control.
How do prescription opioids impact the brain differently than heroin?
Prescription opioids and heroin both belong to the same class of drugs and interact with the brain’s opioid receptors in similar ways. They activate mu-opioid receptors and flood the brain’s dopamine reward pathway with euphoria-inducing chemicals.
There are several key differences in how these substances impact the brain and the associated risks:
- Both prescription opioids and heroin can lead to long-lasting changes in brain structure and function, particularly in areas related to reward processing, decision-making, and emotional regulation. The unpredictable purity and additives in heroin may exacerbate these changes and cause more severe long-term consequences.
- Both heroin and prescription opioids increase dopamine levels in the brain. Heroin may cause a more significant release of other neurotransmitters, such as serotonin and norepinephrine, than prescription drugs.
- Heroin typically enters the brain more rapidly than prescription opioids, particularly when injected or smoked. This faster entry leads to a more intense and immediate “rush” of euphoria. Prescription opioids taken orally have a slower onset of effects.
- Heroin is generally more potent than prescription opioids. A smaller dose is required to achieve the desired effect.
- Injecting or smoking heroin leads to a more rapid and intense high compared to taking prescription opioids orally.
Resources
NIDA. 2021, April 13. What are the long-term effects of heroin use?. Retrieved from https://nida.nih.gov/publications/research-reports/heroin/what-are-long-term-effects-heroin-use on 2024, February 28
NIDA. 2021, April 13. What are the long-term effects of heroin use?. Retrieved from https://nida.nih.gov/publications/research-reports/heroin/what-are-long-term-effects-heroin-use on 2024, February 28
Li W, Li Q, Zhu J, Qin Y, Zheng Y, Chang H, Zhang D, Wang H, Wang L, Wang Y, Wang W. White matter impairment in chronic heroin dependence: a quantitative DTI study. Brain Res. 2013 Sep 19;1531:58-64. doi: 10.1016/j.brainres.2013.07.036. Epub 2013 Jul 27. PMID: 23895765.
Tamargo, J. A., Campa, A., Martinez, S. S., Li, T., Sherman, K. E., Zarini, G., Meade, C. S., Mandler, R. N., & Baum, M. K. (2021). Cognitive Impairment Among People Who Use Heroin and Fentanyl:
Findings from the Miami Adult Studies on HIV (MASH) Cohort. Journal of Psychoactive Drugs, 53(3), 215. https://doi.org/10.1080/02791072.2020.1850946
Qiu, Y., Jiang, G., Su, H., Lv, X., Zhang, X., Tian, J., & Zhuo, F. (2013). Progressive White Matter Microstructure Damage in Male Chronic Heroin Dependent Individuals: A DTI and TBSS Study. PLoS ONE, 8(5). https://doi.org/10.1371/journal.pone.0063212
Gould, T. J. (2010). Addiction and Cognition. Addiction Science & Clinical Practice, 5(2), 4-14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3120118/
Further reading
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What drug causes the most damage to the body?
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