Psychology 101: Intro to Psychology

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Many people have a drink now and then, but how do you know if you have a substance-related disorder? This lesson will help you learn the difference between just having a drink and having an actual problem.

Lauren graduated from college and has been living in a house with a few friends. She's found the perfect entry-level job at a fashion startup, and is happy to find that her weeknights are now free from homework and other school-related obligations. While in school, she'd followed what she felt were typical college drinking patterns; drinking a lot on weekends (and sometimes Thursdays or Wednesdays, depending on what was going on) and not at all on other days of the week. Now that she's graduated, she's found that she likes having a drink when she gets home from work, and maybe also some wine with dinner. She figures this is fine since she doesn't drink as much on the weekends anymore, because she has to drive to the bars and pay for expensive drinks. But her roommates notice, as time goes on, that Lauren's nightly drink/glass of wine actually turns into at least three glasses of wine, and that they'll often come home to find her seriously tipsy - not falling down drunk, but definitely impaired. They don't enjoy hanging out with her when she's always like this, so often they'll make excuses to go hang out in their rooms instead of with her. They're also concerned because she doesn't seem to have any qualms about driving in this condition; she'll be heading out to visit other friends and they'll have to stop her. They start to think she might have a problem with alcohol; or, in the words of the DSM (Diagnostic and Statistical Manual of Mental Disorders), a 'substance-related disorder.'

Though we tend to refer to any substance-related disorder vaguely as 'addiction,' the DSM actually distinguishes between two specific conditions: substance abuse and substance dependence. Lauren's situation sounds more like 'abuse' than 'dependence,' but let's go over some of the key differences.

Substance abuse is defined as a maladaptive pattern of use of a substance; basically, that means that someone like Lauren is using a substance - in her case, alcohol - in a way that has negative social, legal, or work- or school-related consequences. People who abuse substances also tend to continue to use drugs or alcohol in situations where doing so is dangerous. Lauren's drinking is alienating her from her roommates, and she puts herself and others at risk when she drives after she's been drinking.

So Lauren's roommates decide to confront her about her problem. They explain their concerns, particularly about the driving, and ask if she'd be willing to try cutting back. Lauren at first says she doesn't think she has a problem, then admits to feeling hungover at work sometimes and agrees to try to cool it for a while. Her friends notice almost immediate improvement; Lauren still drinks occasionally, but not nearly as often or as much. She didn't seem to have any trouble cutting back.

It's unlikely, then, that Lauren had substance dependence. 'Dependence' is characterized by all the same things as abuse - people use substances despite negative consequences and in dangerous situations. But a patient with 'substance dependence' is unable to quit. Sometimes the dependence is physical, and the patient will experience symptoms of withdrawal when trying to stop. This is more common with some drugs than with others. Heroin addicts are often given another drug, called 'methadone,' to help them with withdrawal symptoms, and some alcoholics must be supervised in the hospital and monitored for potentially life-threatening symptoms like seizures and 'delirium tremens.'

Substance disorders seem to be heritable, though the exact mechanisms are unknown. There are genes that are known to influence levels of the neurotransmitter dopamine in the brain, and high dopamine levels have been shown to make an individual prone to addiction. Drug use itself affects the brain; it may reduce the number of dopamine receptors, thus making it necessary to ingest more of a drug to get the same effect. This is known as 'tolerance,' and plays a role in addiction and withdrawal.

Substance disorders are also affected by cultural norms. Societies that prohibit children from drinking, but celebrate adult drunkenness, have been shown to have higher rates of alcoholism. Total prohibition of a drug, like alcohol in the 1930s in America, seems to result in higher levels of dependence in those who choose to drink anyway.

So, for a quick review: substance-related disorders are divided into two groups, substance abuse and substance dependence. Substance dependency indicates that the individual using drugs or alcohol is physically unable to quit, while abuse is simply a negative or dangerous pattern of use. Certain people may be genetically predisposed to developing substance-related disorders, but socio-cultural factors can play a role as well.