How substances affect the human brain and why we become addicted
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According to Athena Kjell, a Madison area substance abuse counselor, many individuals start using drugs to suppress emotional disorders like depression or anxiety, but some do so simply for experimentation. Unfortunately, they get hooked along the way.
What occurs when a person begins using a drug and what gets a person hooked on a drug involves the manipulation of the brain’s chemistry.
In the brain, inhibitory neurotransmitters are active in the synapse, or the junction space between two nerve cells. Inhibitory neurotransmitters are responsible for calming the brain and balancing moods, but also for releasing dopamine, which helps control the brain’s reward and pleasure centers. Dopamine is released naturally when the the body’s natural opiates activate the opiate receptors thereby shutting down the release of inhibitory neurotransmitters.
Dopamine is unique in that it is both an inhibitory and an excitatory neurotransmitter, meaning dopamine stimulates the brain and also relaxes it. This includes feelings of pleasure in addition to motivation. However, during drug use, which involves stimulating dopamine consistently, dopamine depletion may occur.
When a person uses an opioid, which is the class of drugs that includes both common painkillers and narcotics like heroin, the drug mimics natural opiates, binds to the brain’s opiate receptors and flooding dopamine into the synapse, which leads to pleasurable feelings, or feelings of reduced stress.
Over time, the body starts to build up a dopamine tolerance, and the user starts chasing that dopamine rush that they once felt but can no longer feel due to the depletion.
“This over-activation may be part of what we experience as craving which drives us to want to do the drug again - to try to lower our stress circuit activation and feel ‘better.’ It is easy to see how this may create a vicious cycle which looks like what we call addiction,” said Daniel Bradford, a graduate student in the Addiction Research Center at UW-Madison. Bradford added that drugs and alcohol often elicit similar responses and the term AOD—Alcohol and Other Drugs—is commonly used in the field to lump these addictive substances together.
According to Bradford, researchers still aren’t certain as to what occurs in the brain when someone becomes addicted. The lab’s work with animal models and human testing has given some insights as to what may be occurring in the brain during addiction.
“One thing that appears to occur is that brain circuits responsible for responding to stressors in our environment are somewhat dampened—meaning their activity is lowered—when you do a drug,” Bradford explained via e-mail. “However, our brains and bodies appear to have regulatory mechanisms in place to sort of bring us back to our usual baseline after our stress is lowered by an outside force such as a drug.”
Bradford added that this mechanism may sometimes over-react, making the user feel more stressed than before they used the drug, leading to part of the withdrawal symptoms.
All users will experience some withdrawal symptoms, of which can include both physical and emotional responses, but Bradford explained that the severity of these symptoms vary from individual to individual.
Additionally, it is hard to link withdrawal with relapse.
Kjell explained that with her clients, special dates like anniversaries and birthdays, often act as triggers for relapses. Environmental factors may also do the same.
“If you always get high to Bob Marley, when you listen to Bob Marley you are going to think about it because what fires together, wires together,” Kjell said, explaining that their is a neurological reasoning behind this.
According to Kjell, the hippocampus and the amygdala, two parts of the brain that help elicit memories and emotions, are triggered during learning. If pleasure is related to certain phenomena, the same pleasure will be related with the same phenomena again and again.
Memories and emotions are key in treatment, too. For Kjell, a challenge in her field includes helping those who often cover up their emotions. Some clients will use when they are happy as well as when they are sad, Kjell explained. Each time that they are using, they are making a memory about it, so activities and emotions are automated meaning its evermore challenging to break, Kjell said.
Counseling can change the brain, Kjell explained, but trust plays a key role in the client-patient relationships. Breaking down personal resistance leads to the most success and maintaining personal motivation is Kjell’s goal with her clients.
In the clinic where Kjell works, addicts seeking recovery are required to attend 90 days of counseling as a precondition for receiving their detoxification prescription drug treatments.
Kjell counsels mostly recovering heroin addicts, some of whom are receiving methadone or suboxone at the treatment facility within her clinic. Methadone and suboxone are two medications commonly prescribed to help recovering opioid addicts subsist withdrawal symptoms. In Wisconsin, Medicaid may help cover the cost of these treatment options.
Drugs like methadone eliminate withdrawal symptoms and block cravings without the euphoric effect of other opiates. However, according to the Pat Moore Foundation, methadone addiction and abuse is a dangerous consequence of the treatment. Bradford said his lab is currently investigating a potential addiction treatment technique that repurposes drugs on the market for therapeutic purposes, such as blood pressure medications.
“This work relies on new understanding of the neurotransmitter systems that may be dysregulated in addiction and the recognition that some commonly used therapeutic drugs already affect these neurotransmitter systems,” Bradford said.
When counseling her clients, a technique Kjell said that her and her colleagues use is to help clients build up protective factors, or encourage them to find something to look forward to.
This helps gives them something else to focus on. When a client knows they can only see their family if they are sober, for example, they are most likely to stop using.
Bradford also stressed that counseling will only work if the individual is motivated to change, but added that other challenges may stand in the way.
“Of course we must be careful and recognize that any individual may be truly motivated to change but there may be other roadblocks in their way that not every other individual seeking treatment has. Some examples may be the particular individual’s neurochemistry [or] socioeconomic status,” Bradford said.
Treatment is personalized, just as is an individual’s susceptibility to a drug addiction.
While the consensus is still unclear as to what makes one individual more vulnerable to an addiction than another, Bradford explained that there is a strong genetic component to addiction. He also added pre-existing emotional disorders may put someone at risk.
“We have found some evidence that certain individuals who experience [a] particular large amount of negative emotions (such as more anxiety or irritability) also appear to have particularly powerful responses to drugs such as alcohol. This increased response to the drug could end up relating to whether or not someone becomes addicted to the drug,” Bradford explained.
Kjell agreed, adding that it’s hard to determine which came first: mental illness or addiction.
As for now, the only way of preventing an addiction, Bradford said, is abstinence.Subscribe to The Daily Cardinal Newsletter