Addictive mind altering drugs and alcohol are the bane and burden of civilized humanity, negatively altering the lives and even killing, directly or indirectly, millions of human beings throughout history. Every year many of us Homo sapiens, even those who are well educated or financially successful, find ourselves in jail, losing a job or a family, or even killing another human being as a consequence of our alcohol or drug addiction.
The cost of addiction to our society is enormous. Why are human beings vulnerable and willing prey to the effects of mind-altering substances? Why do human beings take addictive mind-altering substances despite substantial and often horrific negative consequences, such as loss of family, job, and reputation, legal or psychiatric incarceration? Why do some alcoholics and addicts literally drink or drug themselves to death?
Most addicts and alcoholics start using mood-altering substances in response to life stress: the loss of a loved one, financial distress, fear of failure, etc. The negative emotions associated with life stresses are essentially fear, resentment, and sorrow. These emotions and the horrible feeling of stress in our lives can be placated by drugs and alcohol. We primarily seek drugs and alcohol to dampen our negative thoughts and make us feel better. While intoxicated, one could say we have a false sense of Darwinian fitness. We feel stronger, until the mood-altering substance wears off and the life’s hard reality comes into focus again.
What is the current neuroscience behind how drugs and alcohol make us feel better? Although different classes of drugs affect different areas of the brain, the vast majority of recreational drugs stimulate the one common denominator in our central nervous system, the “seat of our soul” if you will, the primitive reward centers of the brain. This part of our brain is called the limbic system.
The limbic system is our primitive brain that has evolved over millions of years to ensure our survival; that is, until mood altering drugs and alcohol were introduced to humanity. The limbic reward centers are the origins of emotion, memory, and motivation. Just like good food or sex, a promotion at work or winning the lottery makes us feel good, a sip of a drink or a hit of a mood-altering drug affect the same feel-good center in our brains.
By stimulating our limbic reward system, drinking and drugging make us feel good; it is that simple. The limbic system is deep in our midbrain and virtually inaccessible to our conscious thoughts. We have difficulty finding the exact words to describe the euphoria we experience during heightened limbic activity as well as the cravings we suffer when these reward centers are deprived.
Proper functioning of our reward centers ensures the survival of our species. It has been said that individuals of our species have three basic instincts: security (food and shelter), reproduction, and socialization. In the absence of mind-altering substances, our brains work wonderfully in the pursuit of instincts. We find food to eat and water to drink, build homes to protect our bodies, and enter into relationships to reproduce, develop social networks to ensure the needs of instincts 1 and 2 are met, and diversify the genetic pool.
These instincts are hard-wired into the deeply seated reward centers of our brain, which command our higher cortical centers dedicated to cognition and behavior, ensuring our survival. Studies from laboratory animals, as well as MRI and PET imaging studies in humans have found dramatic activation of the reward centers of our brain with drugs and alcohol.
Mood-altering drugs hijack the brain’s reward centers, leading to compulsive thoughts and behaviors to acquire the mood-altering substance. Consequently, thoughts and behaviors needed to survive are displaced; all the addict or alcoholic wants to do is take more of their drug of choice. Neuroscience research using functional MRI and PET imaging has shown that mood-altering drugs directly affect the decision-making centers in our brain, which are intimately related to our reward centers. Under the influence of alcohol or mood-altering substances, our judgment is compromised and our ability to make rational choices limited; we are cognitively impaired.
Drugs and alcohol also affect our hormonal balance through the hypothalamic-pituitary axis. With exposure to drugs or alcohol, the stress hormone cortisol is elevated throughout our bodies, which potentiates and perpetuates the addiction, and further causes cognitive impairment and damage to other organ systems. This compromised judgment and other affected cognitive functions may persist for weeks or months.
Unless interrupted with an aggressive recovery program, the limbic cravings which feed the aberrant addictive thinking patterns and behaviors can last a lifetime; that is, if the addict does not die an early, painful death. It is well known in the community of alcoholics and addicts that, even after many years of abstinence, exposure to one drink or drug can ignite a cascade of behaviors and attitudes requisite to acquiring more drink or drug.
Studies in rats have shown long-lasting effects of addiction on the neurotransmitters in the brain: a phenomenon called “neural sensitization” of the limbic reward pathways has been described, which is responsible for the intense craving and return of addictive use after one drink or drug, even after a long period of abstinence.
