CogBlog – A Cognitive Psychology Blog

You probably know of the person. This person  constantly makes poor life decisions despite the negative consequences, like driving while drunk or getting high before class. This person does not have great organizational and planning abilities, maybe he or she blows off important events in order to drink or do drugs. He or she can’t delay the pleasure of getting high or drunk until later, and instead needs immediate gratification from the drug. This person thinks he or she can cram an entire semester’s worth of studying into a few hours, or shows up to a movie set high and expects to preform perfectly. Is the person you’re thinking of dependent on alcohol, cocaine, methamphetamine, or some other drug?

Substance-dependent and an addict, but not everyone is both!

An example of the person mentioned above is Lindsay Lohan. Lindsay is an addict and substance dependent. Addiction is a more severe form of substance dependence. An example of substance dependence might be if you have a cup of coffee every morning, but one day you are late to class and decide to forego the coffee. Because you didn’t have coffee, you get a headache. Your body has become reliant on the caffeine consumption. This is substance dependence, not addiction (Center for Substance Abuse Treatment). An example of addiction might be stealing your mother’s hard earned money in order to buy drugs, and then missing her birthday dinner because you were too high to remember the date. In addiction a person continuously uses and abuses a drug regardless of consequence, increasing the amount they consume to reach the same high and eventually consumption of mass quantities of this drug leads to detrimental health outcomes.  In 2012, approximately 22.2 million people were classified as substance dependent (Substance Abuse and Mental Health Services Administration). Therefore, it is important to understand how being dependent on alcohol, cocaine, or methamphetamine can influence a person’s ability to make decisions. Van der Plas, Crone, van den Wildenberg, Tranel, & Bechara (2009) investigated the cognitive abilities of participants who were undergoing rehab for methamphetamine, cocaine, or alcohol dependency, but were not  addicted to the substances.

One of the cognitive processes that Van der Plas, Crone, van den Wildenberg, Tranel, & Bechara (2009) sought to measure in substance dependent individuals was executive function. Executive function is involved in decision-making.  Sometimes making a decision can be incredibly easy, like deciding whether or not to stop at a stop sign. At other times making a decision can seem very difficult, like deciding whether or not to stop at a stop sign when you are about to pee your pants and your house is just past the stop sign. You can thank your executive function for making a decision in either case. Executive function is our ability to plan, consider multiple options, make difficult and complex decisions, have an accurate sense of one’s own abilities, and to coordinate and utilize other cognitive functions like memory (van der Plas, Crone, van den Wildenberg, Tranel, & Bechara, 2009). Executive function is a part of something called working memory. Working memory is the ability to hold onto information in your head and manipulate it while also completing other tasks. One example of working memory is mental arithmetic; you have to hold on to numbers while manipulating other numbers. Working memory is important in decision making because you need to remember information like the fact that your house is just past the stop sign and that the law mandates that you break for the stop sign while weighing whether or not it’s worth it to break at the stop sign if you might pee your pants.

The Wisconsin Card Sorting Task

Another cognitive function that Van der Plas, Crone, van den Wildenberg, Tranel, & Bechara (2009) were interested in was cognitive flexibility. They evaluated alcohol (n=33), cocaine- (n=27), and methamphetamine-dependent (n=38) individuals on cognitive flexibility using the Wisconsin Card Sorting task. Substance-dependent participants were in rehab and sober at the time of testing. The Wisconsin Card Sorting task is a reliable measure of a person’s ability to hold on to new and old information while changing and adapting to new rules. (Verdejo-Garcia, Bechara, Recknor, & Perez-Garcia, 2005). In the Wisconsin Card Sorting Task you are presented with an array of cards as seen in the image above. The rule of the game is that you must match by symbol, which you eventually figure out through trial and error. So you match your card to card #4. All of a sudden, without your knowing, the rule changes and now when you match your card to card #4 it’s an error.  After a series of incorrect matches, you finally match your card to card #1 and realize the new rule is to match the cards by color. The rule of the game continuously changes, and in order to successfully play the game you need to remember the old rule, figure out the new one, and stop yourself from following the old rule. This task assesses an individual’s ability to adjust to changing situations, an ability called cognitive flexibility. In order to successfully complete this task one needs to have attention, working memory, and the ability to stop continuously trying an old paradigm and implement new ones. An example of a deficit in cognitive flexibility might be if you cling to the old rule and continuously use it despite the fact that the computer tells you it’s wrong, this is called a perseverance error. Using the Wisconsin Card Sorting Task researchers found that substance dependent individuals have generally worse executive function, cognitive flexibility, and working memory (Verdejo-Garcia, et al., 2005). Those who have a history of cocaine or methamphetamine dependence are especially bad at this task, even when they have been abstinent from the drug for a minimum of 15 days (van der Plas, Crone. Van den Wildenberg, Tranel, & Bechara, 2009).

Researchers also evaluated individuals dependent on cocaine, methamphetamine, or alcohol on their decision making abilities. The Iowa Gambling task is useful for assessing a person’s ability to make decisions. The goal of the Iowa Gambling Task is to gain as much money as possible; in order to be successful participants must forgo short-term high money rewards in order to receive long-term profit. The task evaluates an individual’s ability to delay gratification. Most of us have the ability to ignore immediate pleasure in the face of future negative consequences or in order to have future increased happiness, however those individuals who are dependent on cocaine or methamphetamine were not able to do this and often took the short-term money rewards instead of waiting for the bigger payout later. The researchers also found that duration of abstinence was related to improvements in memory, cognitive flexibility, and decision-making.

Whereas cocaine and methamphetamine dependent individuals were impaired in decision-making, working memory, and cognitive flexibility, individuals dependent on alcohol had no deficits in those three domains. Moreover, van der Plas et al. (2009) found that women addicted to cocaine or methamphetamine had more impaired decision-making than men. This suggests that cocaine and methamphetamine may have somewhat different effects in men and women.

So what does this all mean? Cocaine and methamphetamine use may be altering the brain in such a way that inhibits one’s ability to make decisions, adapt to changes in our day-to-day life, and use working memory. Those cocaine and methamphetamine dependent individuals might blow past a stop sign because they can’t weigh the outcome of getting pulled over versus sitting still for a few seconds on their future, they have difficulty doing mental arithmetic because they can’t hold on to and manipulate information, and they might persistently try to do things one way even when the world is telling them it’s time to change. The moral of the story is that if you want your decision-making abilities, executive function, and working memory fully functioning, you should probably stay away from cocaine and methamphetamine!

One tip for improving decision-making ability, cognitive flexibility, and working memory: Don’t become dependent on cocaine or methamphetamine.

To read the original article, click here

References

Center for Substance Abuse Treatment. Clinical Guidelines for the Use of Buprenorphine in the Treatment of Opioid Addiction. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 2004. (Treatment Improvement Protocol (TIP) Series, No. 40.) Appendix C DSM‐IV‐TR Material. Available from: http://www.ncbi.nlm.nih.gov/books/NBK64247/

Garcia-Verdejo, A., Bechara, A., Recknor, E. C., & Perez-Garcia, M. (2006). Executive dysfunction in substance dependent individuals during drug use and abstinence: An examination of behavioral, cognitive, and emotional correlates of addiction. Journal of the International Neuropsychological Society, 12, 405-415.

Substance Abuse and Mental Health Services Administration, Results from the 2012 National Survey on Drug Use and Health: Summary of National Findings, NSDUH Series H-46, HHS Publication No. (SMA) 13-4795. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2013.

Van der Plas, E. A., Crone, E. A., van den Wildenberg, W, P., Tranel, D., & Bechara, A. (2009). Executive control deficits in substance-dependent individuals: A comparison of alcohol, cocaine, and methamphetamine, and of men and women. Journal of Clinical and Experimental Neuropsychology, 31, 706-719.