Addiction is the fact or condition of being addicted to a particular substance or activity. However, the chemistry of addiction goes beyond the chemical hooks in drugs, but also the psychological causes that result in the initial intake of the drugs and then the consistent relapse back to the drug.

What’s the chemistry behind addiction?

Heroin is an opioid which fits into receptors which normally take endorphins and enkephalins. This triggers the reward circuit which produces a dopamine rush, a neurotransmitter released by the substantia nigra and ventral tegmental area. Dopamine is a neurotransmitter used in the brains motivation system, to prompt reward and reinforcement. This is crucial in everyday life, since dopamine can prompt some behaviours which we need to survive, such as enjoying food, and therefore being prompted to eat more of it. However, dopamine can also encourage bad behaviours since it produces a positive response to pleasurable activities. For example, heroin, by stimulating a dopamine rush can reinforce the feel-good experience of taking the drug, and therefore prompt the user to take more in the future. This can be seen in a lot of other situations, such as gambling, where a near miss scenario prompts the gambler to invest more money into the game, since the objective doesn’t seem so far away. This logic would be correct in games of skill, but provides a false sense of motivation to games which involve pure luck, such as slot machines.

What are the psychological causes behind addiction?

An experiment was carried out early in the 20th century involving a rat left in a cage by itself, with the option of two water bottles, one pure water, the other water laced with heroin. Once the rat had tried the water laced with heroin, it kept drinking it until eventually it overdosed and died. However, a similar experiment was then carried out, in which several rats were placed in the cage, with plenty of food, coloured balls and tunnels. Again, they were given the option of pure water or water laced with heroin, but this time, none of the rats ever used this water compulsively or ever overdosed. This proved that addiction was not only caused by the chemical hooks in the drug, but also the environment the rat lived in.

This conclusion can be applied to humans, where we can see that those more likely to take drugs and become addicted are those isolated from society and lonely, just like the rat left alone in the cage, whereas through social inclusion, making connections with others through relationships and education, drug addiction is a pandemic which can be limited.

Humzah Hameed

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