Q: Why does one person become addicted to alcohol, while another to food, and another to gambling?
There are a few reasons but the first is quite innocent: people tend to engage in behaviours that make them feel good. And the first time we did something that made us feel really, really good, that activity gets stored in our nervous system so we readily remember to engage in that behaviour the next time we need to 'feel good' again. (It's in-part how learning works.) That 'feel good' sensation is known in neuroscience as the release of endorphins in the brain. Some also call this endorphin activity, "lighting up the reward centres of the brain" because that's what they see on fMRI scans.
Endorphins are biochemicals that instantly relax the mind and heal the body; they give you that same warm, fuzzy feeling you get from hugging someone you love. In primates, endorphin activity is necessary at every stage of development (newborns to the elderly) to reduce stress. This is why we 'feel good' when it's happening within us. For some, the first time they felt really good (got an endorphin release) was when they sat down with a large cold beer after a stressful day, for others it was the first time they bit into a decadent chocolate cake sitting in their fridge before bedtime, another may have snuck into a casino with his friends while underage and felt a huge endorphin release winning at the slot machines. Innocently enough, some may get a rush of endorphins after receiving an 'A+' grade after a hard exam (for working hard), while less innocently in society's eyes, their peer may have got their biggest endorphin rush from the first time smoking a cigarette with the cool kids in the park.
Initially all the above don't translate to addiction right then and there, in fact some smokers said their first cigarette was awful. But if repeated over and over with these positive thoughts every time the individual seeks to feel really good again, these thrilling activities, matched with their effects on reducing stress, and the conditioning that comes with repeated behaviour, they will soon find themselves under the control of pursuit.
Q: What is 'conditioning'?
Conditioning is simply what neuroscientists call the process of how repetition leads to a larger 'reward' in the brain and body. Some correctly pass it off as just the process of learning, where the behaviour bypasses the slower, conscious, decision-making process because it has been repeated often enough (like riding a bike), and therefore we can complete tasks without our taxing cognition getting in the way. The behavioural economist, and noteworthy psychologist Daniel Kahneman discussed this in his book "Thinking Fast and Slow". Once a behaviour gets past the 'learning phase' where careful thought and consideration is placed into every moment of engaging in a new behaviour (he calls this System 1), and subsists in the unthinking, habit-formed stage (he calls System 2), we're then able to do something without wasting too much brain power doing it. It's a well-known evolutionary fact that all animals get better at anything with "practise" as they say.
Dr. David Kessler described conditioned or compulsive behaviour very eloquently in his book, "The End of Overeating" which delivered the explanation for this phenomenon through the context of compulsive overeating of highly palatable food. He focused a lot on the neurochemical dopamine which heightens our energy, narrows our focus, and increases our drive toward something. Dopamine is hugely powerful; it's what's responsible for feeling 'excited' about something. Dopamine is a natural 'motivating' neurochemical that gets secreted by environmental 'cues' or 'triggers': sights, sounds, smells. You can actually watch the effects of it being released in the brain with children when their eyes light up, their voices get shrill, and they start jumping up and down the moment their parents bring out cookies or candy. Dopamine is released after the individual sees, smells, hears, or perceives a stimuli that they associate with an endorphin release. Dr. Kessler, once head of the FDA and part of the team that took on Big Tobacco lobbyists, also described this dopamine-drive in the context of smoking. For a smoker, even the crinkle of the silver lining in the cigarette package can release dopamine in a habitual user. As does the smell of cigarette smoke, the sight of another lighting up, or even the taste of a coffee if you're used to smoking a cigarette with your morning Americano.
Many are also familiar with dopamine from the experiment commonly known as "Pavlov's Dogs Theory" where Ivan Pavlov rang a bell every time he was about to feed his dogs. He did it so often that he noticed the dogs would start to salivate after hearing the bell, even when the food wasn't in sight yet. This is because the dogs had become so conditioned to the sound of the bell meaning food was coming that dopamine would be released from that sound. They would perk up and get excited to eat, from a seemingly un-related stimuli. Once dopamine was released, nothing could get between the dogs consuming the food.
Q: I get it. Repetition, or 'conditioning', is a big reason why dopamine activity increases in the body. But why can't I just choose not to act once I'm stimulated by a cue? Is dopamine really that powerful that it overrides my conscious choices?
Yes it's powerful. Dopamine assures that conscious desires are overridden by biological desires. Dr. Kessler used examples of studies that are striking to prove this. One described an experiment where a lab rodent was placed in a box with a dividing wire through the middle that would administer an electric shock if the rodent tried to go through it. The rodent had been given Cheetos (highly rewarding due to the sugar, fat, and salt content) every time it was hungry, in place of normal grain-based feed. The rodent was given them to consume repeatedly making the Cheetos even more rewarding: operant conditioning. So when the lab rodent was in the box and the researchers placed the normal grain-feed on the other side behind the electric wire, the rodent was deterred by the electric shock of the dividing wire, and forfeited trying to eat - even though it was hungry. But shockingly, when they placed the Cheetos on the other side of the wire, the rodent went through the electric shock, got to the other side, and ate the Cheetos. The levels of dopamine in the rodent's brain had become so great that it gave him enough energy and drive that it was able to ignore the pain of the electric shock in order to get to the potent stimulus. A similar study was done with a maze. When a Froot Loop primed lab rat was enticed to figure out a difficult maze to get to its normal grain-based rat feed, it gave up after too many difficult turns. But when enticed to figure out the maze to get to Froot Loops at the end, it figured the maze out with astonishing determination, and could do so with increasingly difficult maze setups.
Dopamine is an extremely valiant neurochemical that increases in activity with repetition, and assures you 'act on impulse' despite the consequences that unfold. It gives us a great burst of motivation, strong wit, pain tolerance, and incredible intellect to break down any type of barrier that gets in the way of obtaining a rewarding stimulus. This is why heroin users will be able to inject their arms with a dirty or used needle (something that should normally be highly deterring) in order to get their 'hit'. Heroin releases endorphins in very large amounts, and it does so fast. Again, this reward gets amplified by repeated consumption of heroin (operant conditioning) and the reward is amplified in the face of stress. It is clearly stressful to obtain an illegal drug that might cost more money than the user has, but with heroin as a huge relaxant on stress, and repetition increasing the drive toward heroin above all else, the 'stress, action, heal' reward circle will be unescapable. The mere sight of the needle can release enough motivating dopamine to drive someone to do very horrific and aggressive things they wouldn't normally do otherwise. The biological function of dopamine is set up to assure that the body gets the endorphin reward it not only has become acquainted with due to conditioning, but in fact that it requires, in order to reduce the stress of an addict's very traumatic life.
Q. What does Intermittent Reinforcement have to do with Conditioning?
We learn both through repetition (or, conditioning) of a behaviour, but also through the challenge that is presented in the face of obtaining the reward. How hard or how often we have to work for the reward, the more pronounced that endorphin reward becomes.
We are wired to learn through pleasure and through when pleasure is not delivered. One of the things that this unfortunately makes us susceptible to is intermittent reinforcement. So if you get a reward every time you do something, like open the cupboard to grab a bag of chips, you'll be focused on opening the cupboard every time you A) see the cupboard and B) feel like a reward, and especially if in addition to C) are feeling stressed out. How intermittent reinforcement works is that sometimes, but not every time, the behaviour produces a reward. So if you go to open the cupboard and that bag of chips isn't there, your dopamine activity is heightened, your craving for those chips becomes greater, you have to work harder for it (walk to the store to get them), and the reward becomes greater, or more pronounced.
A huge name in this field of research was B.F. Skinner. His work with rats in conditioning chambers showed us exactly how motivating dopamine can be, and exactly how intermittent reinforcement and repetition can teach us to do something without too much thought getting in the way, and so then, how difficult to control your behaviour will become once it has been ingrained in us by these mechanisms.