Posts Tagged ‘chemicals’
As a result of drug addiction
The drugs contain chemicals that infiltrate the brain’s communication system to disrupt the sending, receiving and processing of information between the normal nerve cells. There are at least two ways that drugs can do this: 1) mimicking the brain’s natural chemical messengers and 2) overstimulation the “reward circuit” of the brain.
Some drugs, like marijuana and heroin, have a structure similar to that of certain chemical messengers called neurotransmitters, the brain produces naturally. This similarity allows the drugs to “trick” the brain’s receptors and activate nerve cells to send abnormal messages.
Other drugs, like cocaine or methamphetamine, can cause nerve cells to release abnormally high amounts of natural neurotransmitters (especially dopamine) or can block the normal recycling of these chemicals in the brain, which is necessary to cut the sending and receiving of signals between neurons. The result is that the brain is saturated with dopamine. Dopamine is a neurotransmitter present in regions of the brain that control movement, emotion, motivation and feelings of pleasure. Typically, the reward system responds to natural behaviors related to survival (eating, spending time with loved ones, etc..), But when it is overstimulated by psychoactive drugs produce euphoric effects. This reaction starts a vicious cycle of reinforcement that “teaches” people to repeat the behavior that caused abuse gratification.
When a person continues to abuse drugs, the brain adapts to the overwhelming surges in dopamine by producing less dopamine or by reducing the number of dopamine receptors in the reward circuit. The result is a lower impact of dopamine on the reward circuit, which limits the pleasure that the user is able to derive not only from drugs, but also events in your life that previously caused him pleasure. This decrease in pleasure requires the addict to continue to consume drugs in an attempt to make dopamine function back to normal. However, we now need to consume a greater quantity of the drug in an attempt to elevate the role of dopamine to normal levels early. This effect is called tolerance.
The long-term abuse causes changes in other chemical systems and circuits in the brain. Glutamate is a neurotransmitter that influences the reward circuit and the ability to learn. When drug abuse alters the optimal concentration of glutamate, the brain attempts to compensate, which can impair cognitive function. Imaging studies of the brains of people addicted to drugs show changes in brain areas essential for the trial, decision making, learning, memory and behavior control. Taken together, these changes can cause the addict find and use drugs compulsively despite adverse consequences knowledge, and leads to devastating behavior. This is the nature of addiction.
Why do some people become addicted to drugs and others not?
No single factor determines whether someone will become addicted to drugs. The risk of contracting this disease is influenced by a combination of factors including the biological makeup of the individual, social environment and age or stage of development it is. The more risk factors you have, the greater the likelihood that the drug becomes addiction. For example: Read the rest of this entry »