Researchers have identified many risk factors which contribute to addiction. These include biology, family history, mental health conditions and exposure to traumatic events as well as environmental influences.
Genes account for 40-60% of an individual’s risk for substance use disorders; other factors, including early life trauma and epigenetics have also been linked with addiction.
Science behind addiction and why some people are more prone to it is still being researched, but one thing we know for certain is that drugs short-circuit a process in the brain called the reward circuit.
This area of our brain produces pleasure when we do things that bring reward – like eating, exercising, listening to music or engaging in creative pursuits. However, drugs cause large surges of dopamine production here that our conscious brain interprets as feelings of euphoria.
Repetition of behaviors that trigger this intense feeling can easily reinforce it and build tolerance to substances, leading to cravings for more of them and an urge to use it repeatedly – thus making addiction much simpler for users.
Glutamate is a chemical messenger between nerve cells that plays an essential role in learning and memory formation.
Brain neurons communicate via nerve cell connections to form small circuits (for managing tasks like memory retrieval) or larger networks (to perform more complex functions, such as sight, hearing and movement). Chemical signals between nerve cells travel via synapses.
Glutamate acts at a synapse to either strengthen or weaken communication signals between nerve cells, ultimately altering function. By releasing sufficient glutamate at just the right time and for just enough duration, messages will successfully travel along their respective nerve cell paths and ensure an efficient communications network is in place.
3. The reward circuit
The reward circuit is a network of brain regions connected by dopamine pathways, including the mesolimbic dopamine pathway which connects ventral tegmental area (VTA) to nucleus accumbens (NAc).
The VTA plays an essential part in mesolimbic pathways because it contains dopamine neurons that project to the NAc via this route. When this pathway is stimulated, dopamine levels in the NAc increase.
Dopamine plays an essential role in recalling pleasant experiences, like meeting with a friend or attending an enjoyable event, which may resurface later when exposed to certain triggers – possibly prompting cravings for drugs or alcohol.
4. Withdrawal symptoms
When abruptly stopping a drug or significantly decreasing their usage, withdrawal symptoms may emerge. These could range from mild to severe and last a long time before subsiding.
Issues could include difficulty sleeping, changing their appearance or becoming irritable and anxious. They also might experience an increase in tolerance requiring them to take more of the drug-like substance before experiencing similar effects.
Withdrawal symptoms can be both distressing and dangerous. They may impede one’s ability to live an ordinary life and lead to relapse if professional help is not sought in time.
Misusing drugs alters a person’s brain in ways known as tolerance and may make the drug less rewarding over time.
So as a result, tolerance makes it harder to experience normal levels of pleasure without drugs.
Some individuals may be more predisposed to addiction because of genetics or the environment in which they grow up, including trauma, abuse, neglect, poor family relations, peer pressure or financial concerns.
Personality traits may also play a factor in addiction development; those who crave thrills and novelty are likely to get hooked on anything that gives them an intense dose of dopamine, making it easier for them to form dependence on certain substances or behaviors.