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Pleasure reward addiction

Desire, reward, addiction
Consulting Educational and Communications Expert
Trends in Education

Learning changes the brain

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Every mind is creative
Click here for an overview of this topic mapped on Prezi.

Think about it . . .

"Most addictive behavior is not related to either physical tolerance or exposure to cues. People compulsively use drugs, gamble, or shop nearly always in reaction to being emotionally stressed, whether or not they have a physical addiction. . .

"No matter which kind of addiction is being referred to, it is important to recognize that its cause is not simply a search for pleasure, and addiction has nothing to do with one's morality or strength of character.

"Experts debate whether addiction is a 'disease' or a true mental illness, whether drug dependence and addiction mean the same thing, and many other aspects of addiction. Such debates are not likely to be resolved soon. But the lack of resolution does not preclude effective treatment."



Understanding addiction

In his book, In the Realm of Hungry Ghosts (2008), Dr. Gabor Maté explains that "there is no addiction centre in the brain, no circuits designated strictly for addictive purposes, The brain systems involved in addiction are among the key organizers and motivators of human emotional life and behaviour; hence, addiction's powerful hold on human beings." The brain's endorphin system soothes pain, both physical and emotional; the dopamine system responds to reinforcement and reinforcers and plays an essential role in learning; and the self-regulation system plays a central role in decision-making "by inhibiting many of the alternative responses that arise in a situation, allowing only one to proceed." Addiction hijacks the brain systems we rely on for survival.
Dr. Maté defines addiction as "any repeated behaviour, substance-related or not, in which a person feels compelled to persist, regardless of its negative impact on his life and the lives of others." All addictions, explains Maté, share the same brain circuits and brain chemicals, and involve
  1. compulsive engagement with the behaviour, a preoccupation with it;
  2. impaired control over the behaviour;
  3. persistence or relapse, despite evidence of harm; and
  4. dissatisfaction, irritability or intense craving, when the object--be it a drug, activity or other goal-- is not immediately available.
Dr. Maté cautions that although addiction has some of the features of illness, viewing addiction as a disease or illness, "acquired or inherited, narrows it down to a medical issue. He emphasizes that "we need to avoid the trap of believing that addiction can be reduced to the actions of brain chemicals or nerve circuits or any other kind of neurobiological, psychological or sociological data. A multilevel exploration is necessary because it is impossible to understand addiction from any one perspective, no matter how accurate. Addiction is a complex condition, a complex interaction between human beings and their environment."

A whole new brain

The following excerpts are from CBC News, "Ancient systems in the brain drive human cravings" (January 2013):

(1) on the brain transmitter systems

Richard Beninger is a behavioural neuroscientist at Queen's University, who recalls that as a student he studied the brain as a collection of parts. "You could see white matter and dark matter and lots of fine detail, right down to the neuron level, but it was all morphology, structure," he said.

"But all of that changed, once scientists began to understand the chemical pathways in the brain. The morphology is still there, but now we know what the transmitter systems are. So we have a whole new brain only in the last 40 years to work with," Beninger said.

(2) on the brain and food addiction

Increasingly scientists also believe food can hijack the brain's reward system. At York University, Professor Caroline Davis is studying the biological basis of food addiction. She says the brain's reward system can be particularly sensitive to highly processed food with combinations of salt, sugar, fat and flavours found nowhere in nature.

"Because they're so palatable, we tend to eat a lot of them and they give us a greater dopamine boost than broccoli does," Davis said. "The things loaded with sugar, loaded with fat, salt, in combination they're very, very hard to resist and there’s evidence that if you eat enough of these foods, in some vulnerable people, they display behaviour that is very similar to the behaviour that we see in other addicts."

When lab rats are given access to sugary food, they binge, and when the sugar is taken away they show physical withdrawal systems that resemble the animal's withdrawal from heroin. Research has shown that dopamine is one of the pathways activated in these sugar-addicted rats.

Pleasure systems

There are two separate pleasure systems in our brain.

The first, the "appetitive" pleasure system, relates to exciting pleasure, such as when we anticipate or imagine something we desire. The pleasurable feeling we experience is from the release of dopamine, the pleasure-giving neurotransmitter.

The second pleasure system relates to satisfying pleasure. It relates to the pleasure we feel when we have consummated or fulfilled what we've been anticipating or desiring. The release of endorphins makes us feel euphoric.

Cravings and the brain

Craving is one of the hallmarks of addiction. Cravings are strong memories that are linked to feelings of pleasure and euphoria. Someone with an obsessive compulsive disorder (OCD) persists in ritualized behaviour that is psychologically debilitating and often physically harmful. However the person with OCD has no craving for the behaviour. There are no memories attached to the behaviour that are linked to feelings of pleasure and euphoria. But for the person with an addiction, memory and anticipation create an intense desire for more of the pleasure-giving experience. As Dr. Maté explains, "she doesn't stop the behaviour in spite of its ill effects. She makes promises to herself or others to quit, but despite pain, peril and promises, she keeps relapsing. There are exceptions, of course. Some addicts never recognize the harm their behaviours cause and never form resolutions to end them. They stay in denial and rationalization. Others openly accept the risk, resolving to live and die 'my way.'"

Cravings may occur when the brain becomes tolerant or sensitized to a drug or experience.


Sensitization, tolerance, dependence

As Norman Doidge explains Chapter 4 of The Brain That Changes Itself, sensitization is different from tolerance. As sensitization develops, less and less of the substance or experience is required for the addict to want it intensely. As tolerance develops, more and more of the substance or experience is required for the pleasant effect to occur. Sensitization leads to increased wanting.

Gabor Maté explains that tolerance is an instance of the addict needing "to use more and more of the same substance or engage in more and more of the same behavour, to get the same rewarding effects." Note also that "although tolerance is a common effect of many addictions, a person does not need to have developed a tolerance to be addicted."

"And then there's physical dependence," he adds. "As defined in medical terms, physical dependence is manifested when a person stops taking a substance and, due to changes in the brain and body, she experiences withdrawal symptoms. Those temporary drug-induced changes form the basis of physical dependence. Although a feature of drug addiction, a person's physical dependence on a substance does not necessarily imply that he is addicted to it... You don't have to be addicted to experience withdrawal--you just have to have been taking a medication for an extended period of time... Withdrawal does not mean you were addicted; for addiction, there also needs to be craving and relapse."

In relation to addiction, Maté explains, dependence means that "the addict comes to depend on the substance or behaviour in order to make himself feel momentarily calmer or more excited or less dissatisfied with his life... Father Sam Portaro, author and former Episcopalian Chaplain to the University of Chicago, said it admirably well in a recent lecture: 'The heart of addiction is dependency, excessive dependency, unhealthy dependency--unhealthy in the sense of unwhole, dependency that disintegrates and destroys.'" 
In the Realm of Hungry Ghosts (2008)

Wanting vs. liking

Distinguishing between wanting and liking makes it clear that craving the next fix is not a simple matter of the addict liking the pleasure it gives and avoiding the pain of withdrawal. Doidge reminds us that addicts want and take drugs when there is no prospect of pleasure, and even when they know they don't have enough of the substance for a high, and they will crave more even before they begin to withdraw.

Do drugs cause addiction?

Gabor Maté emphasizes that "in the cloudy swirl of misleading ideas surrounding public discussion of addiction there's one that that stands out: the misconception that drug taking by itself will lead to addiction--in other words, that the cause of addiction resides in the power of the drug over the human brain." This misconception "obscures the existence of a basic addiction process of which drugs are only one possible object among many... If drugs by themselves could cause addiction, we would not be safe offering narcotics to anyone. Medical evidence has repeatedly shown that opioids prescribed for cancer pain, even for long periods of time, do not lead to addiction except in a minority of susceptible people."

He argues that "we can never understand addiction if we look for its sources exclusively in the actions of chemicals, no matter how powerful they are... It is true that some people will become hooked on substances after only a few times of using, with potentially tragic consequences, but to understand why, we have to know what about those individuals makes them vulnerable to addiction. Mere exposure to a stimulant or narcotic or to any other mood-altering chemical does not make a person susceptible. If she becomes an addict, it's because she's already at risk" (In the Realm of Hungry Ghosts).


Addiction, context, and behavioural principles

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Dr. Carl Hart's High Price - A Neuroscientist's Journey of Self-Discovery That Challenges Everything You Know About Drugs and Society (HarperCollins 2013), uniquely combines autobiography, science and behavioural psychology to challenge prevailing views of addicts and addiction.

In his words, "the emotional hysteria that stems from misinformation related to illegal drugs obfuscates the real problems faced by marginalized people. This also contributes to gross misuses of limited public resources" (xi). Hart makes a critical contribution that should go a long way toward developing new and more effective treatments for addiction.

The recent decades have been an age of new discoveries in neuroscience, and much emphasis has been placed on neuroplasticity and brain chemistry. Hart is cautious of a tendency to reduce "complex human behaviour to simplistic terms like addiction and with trying to blame specific brain chemicals for people's actions" (73).

He shifts the emphasis away from brain chemistry to behavioural principles and argues that mindset, context, and the presence or absence of alternative reinforcers affect whether or not drug use becomes drug abuse, and even whether or not the addicted user will choose to use drugs or not. He supports his very persuasive arguments with research, which includes human as well as animal experiments.

Click here for a review of Dr. Hart's book


Unlearning

Think of learning as the process of neurons firing and wiring together. Learning something new triggers a chemical process called long term potentiation, or LTP, which strengthens connections between synapses to create neuronal networks. "Neurons that fire together wire together." We use these connections, or we lose them. However, once established, these networks are efficient and hard to unlearn. However, the process of unlearning is sometimes important and necessary.

Unlearning involves weakening or losing the connections between neurons, requiring a chemical process called long term depression or LTD. "Neurons that fire apart wire apart." Long-term learing - addiction, for example - requires focused attention, motivation, repetition and practice over a period of time. These conditions are also critical for unlearning if lasting brain changes are to occur.


Descent into porn addiction
Source - Norman Doidge, The Brain That Changes Itself

Doidge recounts the story of Sean Thomas, which first appeared in England in The Spectator. It tells of a young man's transformation from an apparently normal teenager interested in Playboy pictures into an addict hooked on hardcore pornography. The internet freed him from the embarrassment of having to purchase porn in public, and offered the privacy of pursuing his curiosity about online pornography.

Sean's transformation, a plasticity-based process, changed his brain maps as well as his sexual tastes. From a wide array of free "gateway sites" for initiates like him, Sean was surprised to discover that spanking pornography appealed to him. Very soon he found himself, every day and every spare minute, compelled to go online to indulge his need to view spanking porn images. Surprised to discover his interest in spanking, he decided to explore other categories of pornography.

According to Doidge, the spanking images appear to have tapped into childhood experience or fantasy outside of Sean's conscious awareness, and so focused his attention - establishing a critical condition for brain change. He discovered other interests and acquired other tastes in online pornography. Sean was unable to control his craving. With Internet availability 24/7, he began to spending at least five hours every day on online porn, and sleeping no more than three hours at night. Other conditions for brain change were being met - repetition and practice, over time. He was developing new maps in his brain.

Acquiring and satisfying sexual tastes and desires is also an incremental process - another condition for long-term brain change. As tolerance develops, increasingly higher levels of explicit hardcore content, themes and behaviours are needed to excite the online pornography addict. Sexual excitement triggers the release of dopamine, which activates the brain's pleasure centers, strengthening the synaptic connections and neuronal pathways created by and responsible for the addictive behaviour.

Sleep deprivation made his girlfriend suspect infidelity, and eventually ruined his health, landing him in hospital. He also discovered that his friends were similarly hooked on porn. Descending deeper and deeper into pornography, Sean and his friends had met all the conditions for rewiring their brains and changing the brain maps.