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The development of substance use - Why do people use legal and illegal substances?

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Video transcript

- [Instructor] In order to understand substance abuse disorders, we first have to understand why people start using substances in the first place, and there seem to be four main reasons. The first is that substances feel good. They can elevate someone's mood or induce euphoria, and these are things that people like. The second reason is that sometimes people take certain drugs to calm them down. So they can help people find relief from things like anxiety and pain. Substances can also provide some kind of enhancement. So someone might take substances to help them concentrate better at work or to increase alertness, so they can stay up all night studying. And lastly, substances can be involved in important social functions, things like peer bonding and other types of social facilitation, or even peer pressure. And so these four things can help us understand why people start using substances, but we also want to know why they keep using substances. And we can think about that question as it relates to a number of different psychological theories, or psychological models. And the first way, and maybe the simplest way to talk about this, has to do with operant conditioning, and all this is really saying is that we are likely to continue to do things that have been rewarded in the past. And the simplest way of thinking about this is with positive conditioning. So someone takes a substance, it feels really good, and so they will want to do it again in the future. Or maybe they take substances with friends, and it produces a very positive social interaction. It brings them closer together or gives them a reason to come together, and this would reinforce substance use in the future. Another part of operant conditioning is negative reinforcement, and this is slightly more complicated than positive reinforcement. So let's say that you have a terrible headache, and in response to that, you take a painkiller. And that makes the headache go away. This is what negative reinforcement is all about. It says that something that takes away something bad is likely to be repeated in the future. So our person here, will probably take a painkiller the next time that they have a headache. So negative reinforcement tells us that when an action takes away something bad in our environment, that action is likely to be repeated. So let's say that we do have someone, and maybe they're in a lot of pain. They don't just have a headache. Maybe they just had surgery. And so in response to this, they take a substance, either one that's prescribed by their doctor or maybe one that isn't. And when they take that substance, it takes away their pain. Or maybe let's say that someone is getting in trouble at work for falling asleep on the job, and so the next time that individual is dozing off, maybe they'll take a substance to help keep them awake. And because this substance allows them to do a job and because it means that they don't get in trouble, they're likely to use it when they find themselves dozing off again. And as you can tell, these models are really simple, and I actually think that there's something really nice about that simplicity. But maybe because it's so simple, this model also leaves a few things out. In particular, this model seems to ignore all of the negative consequences that can come along with drug use, even before it develops into addiction. And the fact that this is a problem is actually supported by operant conditioning. Because aside from saying that behaviors that are rewarding will be repeated, operant conditioning also says that actions that have negative consequences are not likely to be repeated. And there are a lot of negative consequences that can come along with drug use, imprisonment, losing friends, family, losing a job or financial security, or your health. All of these are very serious things. So why should feeling good for a little bit trump all of the punishments that can come along with drug use? One reason for this might be that studies on operant conditioning show that timing is very important. The reward of the drug, the high, is felt immediately or fairly close to immediately, but the punishments for drug use, the negative consequences, probably won't show up until much later. So let me squeeze the word future in here because it's really future punishments that we're talking about. So what we might actually be seeing here, is that immediate reinforcers are stronger than future punishments. Another problem with these models though, and really with all of these models, is that they're really focused on people's behaviors. They're not really taking things like cognition or conscious decision-making or individual differences. They're not really taking those things into account, and honestly, those things seem like they would be really important. And so I want to shift focus for a minute and talk about some cognitive models for substance use. One of these models is called the self-awareness model, and this model states that once drug use is started, it is maintained because the substance makes us less self-aware over time. And it does this by decreasing our negative feedback. So for example, here, we have Tim, and Tim has some negative feelings about himself. He thinks that he isn't smart or funny or likable. And these thoughts might keep him from interacting with people in the way that he wants to, or maybe they keep him from going to parties or from meeting new people. And so by reducing these thoughts, certain substances might make people feel better about themselves, which would then reinforce the use of the drug. But the problem is that the effects of the substance don't typically end there. As well as making someone less self-aware, substances can also inhibit normal decision-making, or they can make people less cautious. They can also inhibit memory formation. So if someone does something embarrassing while they're on a substance, they might not remember it. And so substances could lead individuals to be less critical of themselves in general, and so they might lose the ability to reflect on how drug use is negatively impacting their lives or the lives of friends and family. A similar model is called the tension-reduction hypothesis, and this theory holds that individuals use substances because they reduce the stress in their lives. So let me redraw Tim, and let's say that Tim has a lot of stress in his life. Maybe he's really stressed out from all of the work he does in college. He's worried about his relationship with his significant other. And maybe someone he knows is sick. Maybe his parent is ill. And so the tension-reduction hypothesis would say that all of these things together would lead Tim to use substances as a way to reduce that stress in his life, or at least to make him feel less affected by the stress in his life. And I think that these two models are useful in figuring out why people might keep using substances, but these models break down a bit when we think about their predictions. So both of these models, both the self-awareness model and the tension-reduction hypothesis, seem to predict that individuals who would benefit the most from reduced self-awareness or reduced tension, they predict that these individuals would be most likely to use and abuse drugs. But that doesn't actually seem to be the case. It just isn't supported by the research. Another reason why people might keep using substances after their initial use is because of modeling, and we're going to call this a social learning model. And this model says that drinking and drug use are learned behaviors. So we know, for example, that people tend to adjust their level of drinking to match the level of those around them. So if someone is in a social group where substance use is normalized and part of social bonding, that individual is likely to model the behaviors from that group. And I want to take a minute to point out something that these three cognitive models have in common, and that is that they all seem to assume, at least on some level, that people's actions will follow their attitudes. So someone wishes to be less self-ware because of negative cognitions, and as a result, they drink. Or someone is really stressed out by the things that are going on in their life, and so they'll drink to reduce that tension. Or maybe they see their friends using substances. Maybe they see their friends drinking at a party, and so they want to join in and drink as well. And so it seems pretty clear that people's actions do follow their thoughts and beliefs, but that might not always be the case. We know from years of psychological research that people will often base their attitudes and beliefs on the actions that they perform and not the other way around, and this is a theory known as cognitive dissonance. So let's say that our guy, and we'll say his name is still Tim, he's in college, and he goes to a party where he sees lots of people who he admires. And these people are all drinking. And let's say that at this point, Tim has never had alcohol before. In fact, he really doesn't believe in underage drinking. But he's at this party, and he sees the people who he admires drinking. And so he decides that he's just going to have a little bit of beer as well. But when Tim finds himself thinking about the situation later, he might find himself in a state of cognitive dissonance. His stated beliefs, that he doesn't think that people who are underage should drink, doesn't go along with his actions. It doesn't match the fact that he drank at this party. And it turns out that as humans, we don't really like it when our actions and beliefs don't match up. It's kind of uncomfortable, and that is what Tim is feeling right now. But the thing is, is that Tim can't go back in time to change his actions. He can't go back and not drink at that party. He's already done it. And so in order to reduce the dissonance between his beliefs and behaviors, he might respond by changing his beliefs, which are the only thing that he can change. So if someone drinks or uses a substance because of peer pressure or even just peer bonding, they might try to deal with the inconsistency in their behavior by deciding that using that substance isn't all that bad. They'll address the inconsistency of their actions by deciding that those actions are consistent with their personal beliefs, and this opens the door to continued substance use in the future.