Compulsive use despite negative consequences is the hallmark of addiction. That means even when the addiction causes job loss, ruined relationships, financial mess, feeling depressed and out of control, we still prioritse our addictive behaviour or substance above anything else in our life.
The classic short definition of addiction issued by the American Society of Addiction Medicine is:
Addiction is a primary, chronic disease of brain reward, motivation, memory and related circuitry. Dysfunction in these circuits leads to characteristic biological, psychological, social and spiritual manifestations. This is reflected in an individual pathologically pursuing reward and/or relief by substance use and other behaviors.
Addictions are characterized by inability to consistently abstain, impairment in behavioural control, craving, diminished recognition of significant problems with one’s behaviours and interpersonal relationships, and a dysfunctional emotional response. Like other chronic diseases, addictions often involve cycles of relapse and remission. Without treatment or engagement in recovery activities, addictions are progressive and can result in disability or premature death.
The American Society of Addiction Medicine also produces a Long Definition. This discusses addiction in great detail and can be found here. The definition was last revised in 2011.
Addiction is the outcome of a process of changes in the brain’s reward system. The reward system in our brain evolved to help us survive by making us seek rewards or pleasure, avoid pain, and all with the least possible effort or expenditure of energy. We love novelty, especially if we can experience pleasure or avoid pain with less effort. Food, water, bonding and sex are the basic rewards we have evolved to seek in order to survive. The focus on them developed when these necessities were scarce, so we experience pleasure when we find them. These survival behaviours are all driven by the neurochemical dopamine, which also strengthens the neural pathways that help us learn and repeat the behaviours. When dopamine is low, we feel urges to prompt us to seek them out. While the desire to seek the reward comes from dopamine, the feeling of pleasure or euphoria from getting the reward comes from the neurochemical effect of natural opioids in the brain.
Today in our abundant world, we are surrounded by ‘supernormal’ versions of natural rewards such as processed, calorie-dense junk foods and internet pornography. These appeal to the brain’s love of novelty and desire for pleasure with less effort. As we consume more, our sensation thresholds rise and we experience tolerance or lack of stimulation from the previous levels of consumption. This in turn ratchets up our need for more intensity in order to feel satisfied, even temporarily. Desire changes into requirement. In other words, we start to ‘need’ the behaviour more than we ‘like’ it as unconscious, addiction-related brain changes take control of our behaviour and we lose our free will.
Other highly processed, less ‘natural’ rewards such as pure sugar, alcohol, nicotine, cocaine, heroin also use the reward system. They hijack the dopamine pathways intended for the natural rewards. Depending on dosage, these rewards can produce a more intense feeling of pleasure or euphoria than that experienced with natural rewards. This overstimulation can throw our reward system out of balance. The brain will cling to any substance or behaviour that helps to relieve stress. Our brains have not evolved to cope with this ever increasing load on the sensory system.
Four key brain changes happen in the process of addiction.
First we become ‘desensitised’ to ordinary pleasures. We feel numb around ordinary everyday pleasures that used to make us happy.
The addictive substance or behaviour works with the second main change, ‘sensitisation’. This means that instead of enjoying pleasure from many sources, we become over-focused on our object of desire or anything that reminds us of it. We believe we can only feel satisfaction and pleasure through it. We build tolerance i.e. we become used to the higher level of stimulation that relieves the discomfort of withdrawal from it.
The third change is ‘hypofrontality’ or the impairment and reduced functioning of the frontal lobes that help inhibit behaviour and allow us to feel compassion for others. The frontal lobes are the brakes that put a hold on behaviours we need to control. It is the part of the brain where we can put ourselves into the shoes of others to experience their point of view. It helps us cooperate and bond with others.
The fourth change is the creation of a dysregulated stress system. This leaves us hypersensitive to stress and easily distracted, leading to impulsive and compulsive behaviour. It is the opposite of resilience and mental strength.
Addiction results then from repeated and increasingly intense use of a substance (alcohol, nicotine, heroin, cocaine, skunk etc) or a behaviour (gambling, internet pornography, gaming, shopping, eating junk food) that causes changes to the brain’s structure and functioning. Everyone’s brain is different, some people need more stimulation than others to experience pleasure or become addicted. The constant focus on and repetition of a particular substance or behaviour signals the brain that this activity has become vital for survival, even when it is not. The brain reorders itself to make that substance or behaviour a top priority and devalues everything else in the user’s life. It narrows a person’s outlook and diminishes their quality of life. It can be seen as a form of ‘over learning’ when the brain gets stuck in a feedback loop of repeated behaviour. We respond automatically, without conscious effort, to something around us. This is why we need strong healthy frontal lobes to help us think consciously about our decisions and respond in a way that promotes our long term interests and not just short term urges.
In the case of addiction to internet pornography, just the sight of a laptop, tablet or smartphone whispers signals to a user that pleasure is ‘just around the corner’. The anticipation of reward or relief from pain drives the behaviour. Escalation to sites that a person previously found “disgusting or not matching their sexual taste” is common and experienced by half of users. Full blown addiction in the clinical sense is not necessary to cause the brain changes that produce the problematic mental and physical effects such as brain fog, depression, social isolation, escalation, social anxiety, erectile difficulties, less attention to work and a lack of compassion for others.
Habitually chasing any dopamine-producing activity can become compulsive by changing what our brain perceives as important or salient for its survival. These brain changes in turn affect our decisions and behaviour. The bad news is that developing one addiction can easily lead to addiction to other substances or behaviours. This happens when the brain tries to stay ahead of withdrawal symptoms by seeking a pleasure hit, or spurt of dopamine and opioids, from elsewhere. Adolescents are the most vulnerable to addiction.
The good news is that because the brain is plastic, we can learn to stop reinforcing harmful behaviours by starting new ones and leaving old habits behind. This weakens the old brain pathways and helps form new ones. It is not easy to do but with support, it can be done. Thousands of men and women have recovered from addiction and enjoyed freedom and a new lease of life.