This video defines our modern concept of disease, referred to by doctors as the “Disease Model”, that’s based on the germ theory of early microbiologists such a Louis Pasteur and Robert Koch. The Disease Model occurs when there is an organ (bone, liver, etc.) that gets a defect and as a result it brings a symptom (a physical manifestation at a cellular level).
Causal Model: Organ + Defect → Symptoms
Doctors do not chase symptoms they chase the defect. Prior to the Disease Model’s implementation they would treat only symptoms instead of finding the cause aka the defect. This modern scientific based model doubled the human lifespan in only 100 years. At that time doctors could not readily fit the disease of addiction into that model, and declared that it was no longer a disease and addicts were no longer patients.
Addicts soon became the problem of the criminal justice system when doctors denounced them 100 years ago. Today the U.S. prison system is filled with people who are in custody due to drugs and alcohol, and the things they did on drugs and alcohol. In the last 20 years, neuroscientists learned that parts of the brain are involved in the defect, and the defect in that organ does show their behaviors as a symptom of that disease.
In this short video Dr. McCauley explains the two main parts of the brain that are important in addiction: the midbrain and the cortex. The bumps (called sulci) and the grooves (called gyri) on the outside of the brain compose the frontal cortex. Half a million years ago when the primate brain exploded and evolved into the size of what the human brain is now, the brain had to fold on itself to create more surface area, and that’s why it’s wrinkled. Our conscience life (all the things we hear, see, taste, touch) occurs in the cortex.
This short video explains that morality, judgment, and personality occur in the brain’s frontal cortex. This is where choice is conceived. Doctors thought that the defect of addiction had to occur in the frontal cortex because it’s a “choice”. We know now that addiction occurs much deeper down in the midbrain.
This short video explains how the midbrain functions to keep our species alive. The midbrain does not think, make choices, or handle consequences. It tells us to eat, defend, ourselves, and keeps us alive, while the cortex controls how we feel, think, or act.
When addiction is present the brain’s guiding control fails, and turns down the rational decision-making cortex. An addict’s brain is hijacked by the drug as its mechanism for survival. Staying alive by eating is no longer important to the midbrain; the relief is in the drug.
Scientific tests involving mice helped to discover this “malfunction” of the midbrain, and researchers learned that to an addict drugs and survival are indistinguishable.
To identify and prioritize the things that are good for survival, the midbrain makes them pleasurable. When a drug and survival are indistinguishable to a person’s brain, they cross into line of the addiction. 9 out of 10 people are not addicts. The other 1 out 10 suffers from a defect of hedonic capacity, or pleasure sense, in the midbrain.
When an addict suffers from a defect in the midbrain it affects their ability to perceive, process, and then act upon pleasurable experiences. A person with a defect in their pleasure sense is not interpreted in the same way as someone who is deaf (defect in ears) or blind (defect in eyes). Because this defect is based on “pleasure”, addicts are perceived as immoral and go to jail by the hundreds of thousands.
This short video explains how the brain creates a pleasurable experience by combining several levels of processing together into a Pleasure Construct. The French author Marcel Proust sensationalized the Pleasure Construct when he described his experience eating a Madeleine Cookie:
“No sooner had the warm liquid, and the crumbs with it, touched my palate, a shudder ran through my whole body, and I stopped, intent upon the extraordinary changes that were taking place. An exquisite pleasure had invaded my senses…”
The exquisite pleasure of a Madeleine Cookie dipped in warm tea brought back memories of childhood that laid dormant for years until triggered by the taste of the cookie. The Pleasure Construct brings reward, taste, smells, places, memories, and emotions together into a single sensation. We don’t experience them individually, but instead they are woven into one experience.
With addiction, something goes wrong at every level of brain processing as the brain tries and fails to create a pleasurable experience. Addiction is pleasure unwoven.
This video explains the five theories of addiction in Neuroscience. The theories do not conflict with each other; they actually fit together. All levels shows what’s going wrong in the “brain processing” while creating a pleasurable experience.
5 theories of Addiction in Neuroscience:
Any one layer of brain processing contains the levels of brain processing before it. If there is a problem in the first layer of processing it will affect the next layer up to the frontal cortex.
We all have a hedonic system and therefore are at risk to becoming addicts. Some people are more likely than others to become addicted based on their genes. Dr. Marc Schuckit of UCSD, found a difference in the genetics of how people respond to alcohol (genetic low responders and high responders).
Genetic low responders need more alcohol to get drunk so they drink more and are therefore more vulnerable to becoming alcoholics, whereas high responders are less vulnerable. Genes alone are not enough to bring an alcohol addiction; something in the environment has to turn that addiction on.
When our brains process a rewarding experience dopamine is released by the nerve cells (neurons) in the midbrain. It tells the brain when the reward is salient and when it’s better than expected. With addiction, dopamine is more about drug-wanting than drug-liking.
Drugs cause huge surges of dopamine, far more than the brain was designed to handle. They fool the brain into thinking the drug is better than expected giving it a higher priority to survival. As the drug climbs the survival list, the brain thinks it’s better and better (even though it’s not), eventually putting it in the number one spot. It is this irrational assignment of value that brings persistent use despite negative consequences.
In this video Dr. McCauley uses The Periodic Table of Intoxicants and Addictions to explain the Dopamine Hypothesis and its potential for Cross-Addiction.
There are many drugs that release dopamine such as the usual drugs: Alcohol, Marijuana, Cocaine, and Nicotine. These form The Periodic Table of Intoxicants along with stimulants, entactogens (Ecstasy), entheogens (used to be called hallucinogens), dissociatives (PCP, Ketamine), sedative hypnotics (Valium, Xanax), hypnotics (GHB, Ambien), opioids (Morphine, Heroin, Methadone), inhalants and anabolic-androgenic steroids. They all have the ability to release dopamine in the pleasure area of the brain.
The Dopamine Hypothesis implies that if a person has a problem with one drug they are liable to develop a problem with any or all of the others. Not only chemicals release dopamine, but behavior can as well. Those who manipulate behaviors with things such as food, sex, and gambling, and codependency, can get the same surge of dopamine that they would from a drug. Cross-addiction occurs when a person tries to replace their chemical addiction with manipulating behaviors, and they end up having a very hard time staying sober from both.
This video discusses glutamate, the neurotransmitter that creates memories. When a person uses a drug they remember things such as the time of day, the sights, and the smells. If they are exposed to these again the glutamate releases “drug cues” or the motivation to get the drug. This chemical triggers a drug memory into drug-seeking behavior.
This video explains how drug use causes dopamine and glutamate to malfunction in the brain.
Normally, dopamine sends reward processing up to the frontal cortex. The frontal cortex then sends glutamate neurons back down to the midbrain. The up and down communication teaches the brain to recognize the things that are important to survival. Drugs go straight through this mechanism and wipe it out.
The surges of neurochemicals carve deep channels into the brain making drug pathways stronger and the normal functions weaker. Dr. Steven Hyman of Harvard University calls drug addiction a pathological overlearning of the drug and all that goes with it. It isn’t a normal memory – it’s a drug hyper memory – that leaves an addict vulnerable to relapse even after years of abstinence.
This video discusses the three causes of Relapse:
Dr. McCauley explains how an addict’s need to relieve stress is below their level of consciousness. When the brain is stressed it goes to the thing it knows will relieve the stress. That’s why many addicts relapse at the worst times (before court hearings, job interviews, and family reunions). It’s not because they don’t care, it just happens because the drug is associated with relieving stress and survival.
This video discusses how brain scans have helped to understand the science of addiction.
Dr. Peter Kavlivas, of The Medical University of South Carolina and Dr. Nora Volkow, director of the National Institute on Drug Abuse used brain imaging to demonstrate the abnormal activity in the frontal cortexes of addicts.
They believe this activity (something going wrong in the cortex) is the basis of the overwhelming importance addicts put on drugs. Brain scans show dopamine is significant in the early stages of addiction, but the glutamate projecting back down the frontal cortex is the final pathway to addiction.
Rational judgment and choice is only possible if the hedonic and emotional processing received by the cortex is accurate. The uncontrollable urge for how the drug feels causes an addict’s memory of a prior commitment or what happened the last time they drank or used, the importance of their family, and any punishment that may await to become invisible to the addict.
This video describes the state of an addict’s brain, which can be referred to as Hypofrontality. What was once a healthy functional decision-making frontal cortex is reduced by overactivity in some areas of the brain, while it lacks activity in others. Hypofrontality causes personality change, impaired decision-making, and a loss of insight during the early stages of addiction.
What begins as a genetic disorder ends in a disorder of choice, and Hypofrontality connects both with the feeling of “craving”. For an addict “craving” is not the same as liking something a lot, like when you say, “I’m craving chocolate”. Craving is a powerful tool that connects the drug to survival and your mind tells you to do anything to get that drug.
Dr. McCauley explains how “The Choice Argument” does not work when explaining an alcoholic’s “craving”. They can choose not to drink if there’s a gun to their head, but they cannot choose not to crave.
The brain state of an addict does not need to be permanent, it can heal and the frontal context and decision making function can be restored. There are many ways to reach recovery, such as going to NA or AA, as long as the person handles their addiction on a daily basis.
Recovery is possible and people become sober from their addictions all the time. What people in recovery have in common is they stop doing the things or curtail the things that cause a surge in dopamine, learn to cope with cravings and drug cues, and become better at managing stress in a social and spiritual context. After they have spent some time in recovery, the frontal cortex is able to regain control and the power of choice is restored.