Melissa Walsh

Brain Changes and Addiction

Salem Press | 2011 | Salem Health: Addictions & Substance Abuse

Essay title:: Brain Changes and Addiction Category: Health Issues and Physiology

Definition: Neuroscientists agree that the chronic use of drugs and alcohol profoundly impacts the brain. As a person grows a dependency on a substance, the brain undergoes lasting changes. Due to the changes in the brain, a recovering addicted is vulnerable to relapse .

Personality Disorders of the Addicted

With advances in brain-imaging technology, medical experts conclude that addiction is not merely a defect in behavior or will, but a disease of the brain. Behavioral experts conclude that personality disorders can lead to substance abuse and result from substance abuse.

Until recent years, clinicians treating substance abuse did not connect substance abuse disorders to personality disorders. Today substance abuse treatment usually involves detection, management, and treatment of a patient's underlying personality pathology. A personality disorder is presented as persistent, unusual behavior relative to the cultural expectations for normal behavior and are usually observed during childhood or adolescence. According to specialists Shelley McMain and Michael Ellery in a 2008 article on the International Journal of Mental Health and Addiction, persons with a personality disorder are impaired in at least two of the following behavioral functions: "impulsivity, interpersonal functioning, affectivity, and cognition." They found that the most common disorders among addicts are anti-social personality, borderline personality, and histrionic personality and recommended "a thorough diagnostic assessment involving screening for personality pathology" for individuals "seeking treatment for addiction problems."

According to psychiatrist Raymond Anton, between 40 and 60 percent of those dependent on alcohol inherited the tendency to abuse alcohol. Most of these are male. Gene studies suggest that certain people are born with DNA making them more susceptible to becoming alcoholics. Anton concluded, "Whether it is heredity (the genes we are born with) or an interaction between these genes and environmental events and/or between genes and substances themselves, there is no doubt that the genetic brain differences are likely to be at the root cause of addiction."

Brain Responses in Behavior Scientists agree that alcohol and drugs impact the brain's biochemical process, altering the way neuroreceptors receive, process, and send information by overtaking the brain's neurotransmittors or by over-stimulating the brain's pleasure center. Just as the brain connects the consumption of food and water as necessary for survival, with substance abuse it links alcohol or drugs to sustainment. The over use of substances disrupts the brain's normal biochemical balance and mechanisms for controlling pain, anxiety, euphoria, impulsiveness, etc. Because alcohol and drugs impact biochemical processes in the brain, they also impede the brain's ability to control decision-making and judgment. The desire for the substance of choice to flow into the brain becomes an all-consuming desire for the addict, and substance abuse becomes an intrusion into the brain that it will never fully recover from.

A person's risk for addiction is linked to the reward and pleasure system in the brain. For many, "an intense feeling of euphoria" is experienced when first trying the substance, according to specialist Timothy W. Parker. The user's brain cultivates an deeper attraction to the reward of the substance. In contrast, once the effects of the substance wear off, the person's mood sinks to a severe low. The brain responds by craving the substance again, and the cycle continues, evolving into addiction. "Although they are motivated to take more of the drug to duplicate the original high," Parker explained, "drug abusers will never again attain that intensity of pleasure. Clearly some reaction in the brain has reduced the effect of the drug. It is interesting that this occurs so rapidly; the brain is a quick study."

This reduction of the effect of the substance characterizes the next stage of addiction. The user ingests higher doses of the substance, increasing a tolerance for the substance. At this stage, withdrawal symptoms, which are the opposite of the high, persist if the user does not ingest the substance regularly. If a substance's effect is relaxation and numbness, as with heroin, withdrawal symptoms are restlessness, tremors, and pain. Withdrawal from a stimulant like cocaine includes fatigue and depression.

The final stage of substance abuse is recovery − after an addict undergoes treatment and is abstaining from the substance. Even when withdrawal symptoms have dissipated, the recovering addict remains extremely vulnerable to a reactivation of a craving for the substance, triggered by social cues and visual stimuli. Even in recovery the addict will continue to be plagued with a condition in the brain that blocks the "just-say-no" solution to substance abuse. According to psychiatrist Raymond Anton in a 2011 article in the Journal of Law, Medicine and Ethics, MRI images of the brains of alcoholic and non-alcoholic subjects show a difference in chemistry in the dopamine-activation part (pleasure center) of the brain. Alcoholic brains show much more activity than those of non-alcoholics when processing images of alcoholic substances. Even during periods of abstinence, Anton found, addicts experience a dopamine-receptor deficiency when challenged by alcohol stimuli, leading to pleasure cravings and consequently poor judgment.

Physical Brain Impacts Drugs and alcohol influence synaptic transmission in the brain and activate the release of an increased amount of the pleasure chemical known as dopamine into the brain's the neural circuit. Depending on the substance, two structures in the brain are impacted: the ventral tegmental area (VTA) and the nucleus accumbens (NA). VTA neurons influence the NA, which is where dopamine is released. Most drugs either activate VTA or directly affect NA dopamine levels. The ethanol found in alcohol directly increases dopamine release in the NA.

As a person becomes addicted, the tolerance to the substance increases. Physically the brain changes to put controls, called neuroadaptations, on the substance's effect on dopamine release and shut down NA receptors. The amount of dopamine released with the ingesting of the substance subsides, causing the individual to consume more of the substance to gain the desired level of pleasure. The brain also releases controls to regulate the addicts emotions, activating moods of anxiety or depression as a sort of anti-reward system in the addict's brain. The addict's pursuit of pleasure facilitates higher doses of the substance, leading him or her potentially to overdose.

Substance abuse inflicts long-term changes to the brain The neuroadaptations the brain produces to control the release of dopamine and regulate emotions remain with the addict even after treatment and years of abstaining. Addiction alters the prefrontal cortex of the user, causing the reduction in neuron activity in this part of the brain. Directly related, other parts of the brain release a neurotransmittor known as glutamate, which impairs the addict's decision-making ability. Glutamate facilitates impulsiveness and focus on immediate reward. Consequently addicts often engage in reckless behavior and rehabilitated addicts are prone to relapse when faced with substance-related stimuli. The amygdala, or memory part of the brain, is impacted as well, enhancing emotional memories associated with being high, thereby making stimuli triggering these memories difficult for the addict to resist.

Treatment In a 2011 editorial, the editors of Drug Week asserted, "Effective prevention and treatment of addiction requires a clear understanding of the complex brain mechanisms that underlie addictive behaviors, and research has provided a fascinating view of how substance abuse hijacks neuronal circuits involved in reward and motivation and causes profound and persistent changes in behavior." Critical for effective treatment is the understanding of how the brain changes over time with substance abuse. According to Parker, an estimated 90 percent of treated addicts relapse. Therefore, while many benefit from initial treatment for a period, more needs to be done to understand the long-term impact to the mind of the recovering addict to facilitate addiction recovery for a lifetime. Central to the Alcoholics Anonymous (AA) approach to treatment is the notion that the alcoholic has no power over the addiction. Assuming that addiction is a chronic life-long condition and that the addict's brain cannot be cured medically, AA treatment involves intervention, group therapy, counseling, and accountability.

Nonetheless, the pharmaceutical community is seeking to develop pharmacological cures for addiction. With advances in neuroscience , new pharmaceutical treatments have been proposed. Some are designed to make an individual physically ill if ingesting an abused substance. Others are a weaning mechanism. Generally, drug treatment taps the brain's natural dopamine regulators, gamma-aminobutyric acid (GABA), the brain's inhibiting mechanism, and glutamate, the brain's excititory mechanism. However, as pharmacologists seek to leverage pharmaceutical breakthroughs to develop remedies for substance abuse, skeptics insist that treating substance abuse with substances will not offer a lasting cure. Suggesting that there is more to beating addiction than physically treating the brain, they warn that the spiritual element should not be dismissed.

Melissa Walsh

Further Reading

"All About Addiction." Drug Week. (March 2011).

Anton, Raymond. "Substance Abuse is a Disease of the Human Brain: Focus on Alcohol." Journal of Law, Medicine and Ethics (Winter 2010).

Denizet-Lewis, Benoit. "An Anti-Addiction Pill?" The New York Times Magazine (June 25, 2006): 48(L).

McMain, Shelley and Michael Ellery. "Screening and Assessment of Personality Disorders in Addiction Treatment Settings." International Journal of Mental Health and Addiction (Jan. 2008).

Parker, Timothy W. "Brain Changes in Substance Abuse: Implications for Treatment." Forum on Public Policy: A Journal of the Oxford Round Table (2010).

Simon, David and Deepak Chopra. Freedom from Addiction, Deerfield Beach, FL: Health Communications, 2007. Addiction specialists offer information for recognizing addiction and methods for recovery.

Westreich, Laurence M. Helping the Addict You Love. New York: Simon & Schuster, 2007. A guide for family member and friends of addicts in leading the addicted into and through treatment and recovery.

Web Sites of Interest Center for Substance Abuse Treatment (CSAT) http://csat.samhsa.gov

Narcotics Anonymous http://www.na.org.

WebMD's E-medicine Health http://www.emedicinehealth.com/narcotic_abuse