Learning how the brain responds to pleasure has blasted the doors of addiction research wide open. Though there’s still a vast amount of unknowns where the neuroscience of substance abuse is concerned, researchers understand how the brain’s reward and pleasure centers are hijacked by drugs and alcohol.
In addition, doctors and scientists recognize addiction as a chronic disease that changes both the function and structure of the brain.
What Are 3 Distinct Aspects of Addiction?
Cravings for the Addictive Substance or Activity, such as heroin, prescription pain medications, or alcohol. Brain imaging has also shown that other pleasurable activities, such as gambling, shopping and sex, can affect the brains of some individuals in the same way as drugs and alcohol.
2. Loss of Control
Loss of Control over the use of the substance or participation in the damaging behavior.
3. Continued Use
Continued use of the Addictive Substance or participation in the behavior even after the negative consequences have become apparent.
The Neurobiology of Addiction
Understanding the neurobiology of addiction, it’s important to know that the brain reacts to all pleasure in the same way. Whether it’s in response to a long jog, a raise in pay at work, a drink of whiskey or even smoking a cigarette, pleasure has a unique signature in the brain.
A cluster of nerve cells underneath the cerebral cortex, near the front of the brain, is so associated with good feelings that neuroscientists refer to this region, the nucleus accumbens, as the “pleasure center.”
Dopamine, a naturally occurring chemical in the brain, floods the “pleasure center” when substances like alcohol, cocaine or nicotine are ingested. This brings on feelings of euphoria and wellbeing.
The likelihood that a person will become addicted to a substance or behavior is directly related to how fast and reliable these things create the release of dopamine in the brain. A stronger, faster dopamine release will generally lead to abuse and dependency problems.
Newer studies have shown that dopamine, which is also associated with remembering and learning, may in fact lay down memories of the speedy satisfaction drugs and alcohol generate, conditioning the brain to crave the substance. The brain is then chemically motivated to seek out whatever causes the pleasure.
The natural release of dopamine isn’t as quick and intense as it is with drugs and alcohol, and the consistent use of addictive substances makes it even more difficult to experience naturally occurring pleasures.
With substance abuse, the brain adapts to the regular release of dopamine and causes a tolerance, meaning individuals have to use more and more of a substance to achieve a similar “high.”
Scientists have shown that once the brain has memories of the “high” and has gone on to create a tolerance, compulsion takes over.
The brain is now completely hijacked by addiction.
Compulsion occurs when the pleasure from a behavior or a drug is gone, but there is a persistent, often overpowering, drive to recreate the good feelings regardless of the consequences.
Structural and Functional Changes in the Brain From Addiction
When a person has heart or lung disease, the structure and function of the heart or lungs change in regard to the disease.
The same is true of addiction.
Using imaging tools, doctors and scientists can actually see these changes in the brain, as illustrated below.
Structural Changes in the Brain Caused by Addiction
Here are two images that show how addiction changes the structure of the brain, as viewed from the top and front.
A healthy brain image is shown on the left, and an addicted brain is shown on the right.
It’s easy to notice the physical differences between the two and how the brain structure has changed over time.
Functional Changes in the Brain Caused by Addiction
The next two images show how addiction can change the function of the brain, as viewed from the top and front.
The healthy brain shown on the left has much more activity than the addicted brain on the right.
If you ever wanted to know what the brain on drugs or alcohol looks like over time, these images sum it up.
The structural and functional changes in the brain caused by addiction to drugs or alcohol happen over a period of time.
For some, this period of change is more rapid due to many factors, including genetics, type and amount of substances used, as well as the method of use (oral versus intravenous injection), among others.
For heavy users that have been addicted for a long time, these changes might be permanent.
It’s important for drug and alcohol abusers to understand, the brain is neuroplastic, meaning it can change over time.
If stopped, and proper treatment is administered, many of the structural and functional brain changes can be reversed if caught early enough.
Effective treatment for addiction can be successful with proper counseling, support and attention to any underlying issues, such as bipolar disorder, depression or anxiety.
The brain will begin to heal and be able to experience normal pleasures from day-to-day living.
Acknowledging that addiction is not a moral failure, but a complex disease will lessen the stigma surrounding these issues, and more people can begin to seek for their addiction.