The Addiction Process
Addicted persons use substances for a variety of reasons, and pleasure is certainly one of them; at least at the onset. Over time, these drugs become less pleasurable at the same doses and require users to take more in order to evoke the same pleasurable feelings. Continued use and increasing dosages help to further the addiction process as the chemicals begin to reprogram the inner workings of the addict brain.
How Do Substances Affect the Brain?
Addiction and pleasure are intrinsically linked due to the nature in which drugs work. Drugs like heroin and marijuana create pleasurable sensations due to the chemical structure of the drug mimicking certain brain chemicals – or neurotransmitters – such as Anandamide. While chemically different, these imposter chemicals are similar enough in composition to mimic the effect of your brain’s natural neurotransmitters. Anandamide isn’t responsible for pleasure directly, but it does have a relation to several other functions that help to trigger the release of dopamine, such as mood and appetite. In addition, Anandamide helps to regulate pain, which increases the natural response to pleasure.
Other drugs, such as methamphetamine and cocaine take a more direct approach by tricking these neurons into releasing large amounts of a natural neurotransmitter called dopamine. Dopamine is responsible for sending signals to other cells, which plays a major role in reward-motivated behavior. Over time, the brain has evolved to reward certain behaviors that could be critical to the survival of the species, such as eating, exercise, and sex, by triggering the release of additional dopamine. This release of dopamine triggers a pleasurable effect and leaves the user wanting more.
Dopamine and Pleasure
James Olds and Peter Milner, both of McGill University, first discovered the so-called “pleasure center” of the brain in 1954. Olds and Milner implanted electrodes into the brains of lab rats and found that rats developed a habit of pushing a lever that stimulated the nucleus accumbens (NAcc) leading to a release of dopamine in the rats. The rats became so fixated on pushing this level that they’d often forego food or drink in order to continue flooding their bodies with dopamine.
The same activity describes addiction in humans. Addicts become so accustomed to this rush of dopamine, that they’ll often forego otherwise important obligations such as eating, spending time with family, school, work or friends in order to continue flooding their bodies with these “feel good” chemicals. As such, pleasure becomes an integral part of the addiction that it leads addicts to continued use (and often increasing dosage amounts) in order to maintain this state of well-being, or attempt to escape reality.
This pleasure, however, is often short-lived. Over periods of extended use, the body begins to adapt to the substance, which leads to its release of less dopamine. In addition, your body begins to create a new baseline for mental well-being due to this increase in dopamine, and previous (sober) levels of dopamine release often lead the user to feelings of depression or anxiety. Also present is the sickness created by withdrawal for the substance as your body begins to desire more in order to get back to its new baseline normal state.
Due to this physiological reaction, many addicts report that, over time, drugs become less and less pleasurable, and continued use is merely a way of avoiding sickness associated with withdrawal.