The New IQ: Use Your Working Memory to Think Stronger, Smarter, Faster. Tracy Alloway

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СКАЧАТЬ Task ¹

      Sad Happy Sad Sad Neutral

       2-Back Task

      Sad Neutral Sad Happy Neutral Happy Happy

       The words that are repeated in the 1-back or 2-back task are in bold.

      Levens and Gotlib measured the speed and accuracy of the responses. There was no significant difference between the depressed and nondepressed groups on the 1-back task. The difference emerged when it came to remembering the emotional expressions on the 2-back task, the task that engages working memory. The depressed individuals were faster in matching sad faces, while the non-depressed adults were quicker in matching happy faces. The psychologists suggest that the way we use working memory to process emotions played a role in this difference. They conclude that depressed individuals were more likely to keep sad emotions in their working memory, while the non-depressed people keep happy emotions in their working memory. This suggests that your working memory Conductor can be a double-edged sword when it comes to happiness: you can use it to fixate on the bad, or the good. Paraphrasing Aristotle, it’s your choice. But as we will see, those with a stronger working memory tend to choose happiness.

      To take her research a step further, Levens teamed up with Elizabeth Phelps of New York University to investigate what happens in the brain when people use working memory to process emotional information. They asked participants to perform working memory tasks in which they had to recognize positive and negative emotions. Participants were first shown a string of negative emotional words—like murder and terror—on a computer screen. They were then shown a single word (known as the target word) and asked to determine whether it was in the list of negative words they had just seen. The experimenters did the same with positive words. These tasks required the participants to use working memory to keep in mind the lists and then compare the target word with the lists. At the same time, the scientists observed the brain activity of the participants using functional magnetic resonance imaging (fMRI) scans. The scans revealed that blood rushed to the PFC, and the researchers showed that working memory plays a role in judging positive and negative emotions. But distinguishing between positive and negative thoughts isn’t the same as feeling a negative or positive emotion. So does having a strong working memory actually help make us feel happier?

      Working Memory Fires Up the Feel-Good Brain Chemicals

      The human brain is coursing with chemicals that create happy feelings. Two of these feel-good chemicals are the neurotransmitters dopamine and serotonin. Dopamine is a pleasure and motivation chemical that is released in the brain whenever you do something enjoyable. The quick hit of dopamine produces a short-term feeling of euphoria, which encourages you to repeat the behavior. Serotonin is known as the Zen neurotransmitter because it is associated with feelings of deep and subtle satisfaction and long-term happiness. Serotonin is so critical to happiness that the most commonly prescribed antidepressants work by increasing its level in the brain.

      Exciting research is showing some surprising links between working memory and the production of both dopamine and serotonin. One study from researchers at the University of California, Berkeley, used positron emission tomography (PET) scans to investigate the relationship between working memory and dopamine. The first step in this trial was to test the participants’ working memory to identify individuals with high and low working memory. Then both the strong and weak working memory groups underwent PET scans to measure dopamine production in their brains. The researchers found that the brains of participants with good working memory made more dopamine, while those with poor working memory made less.

      In another study conducted at the Heinrich-Heine University in Germany by Ruediger Grandt and colleagues, PET scans were used to examine whether there is any link between working memory and serotonin. The study revealed that when participants performed a working memory task that involved remembering a sequence of faces, they experienced an increase of serotonin that participants completing a non–working memory task did not experience. What we find particularly exciting about this study is that it is the act of using working memory that was linked to the surge in serotonin. In other words, simply using your working memory may make you happier. If you are feeling grumpy, you may want to try to engage in activities that use your working memory, to see if that dopamine and serotonin boost can improve your mood.

      Working Memory and the Glass Half Empty

      At the other end of the spectrum, we wanted to investigate how working memory is related to unhappiness, in particular, depression and rumination. Rumination is the term psychologists use when people fixate on things, often negative. It is an unproductive style of thinking that is difficult to control or stop, and it tends to be linked with strong emotions like worry and fear. It is like your working memory Conductor is playing the same sad song over and over again.

      Susan Nolen-Hoeksema, a psychologist at Yale University, has been investigating rumination for more than a decade, and her research indicates that people who ruminate are more likely to develop depression; moreover, they experience more severe symptoms of depression. We wondered what effect rumination might have on working memory and discovered that emerging evidence suggests a relationship. Robert Hester and Hugh Garavan of Dublin’s Trinity College artificially increased rumination on negative thoughts by showing adults lists of words with negative connotations like murder, anger, and fight. They found that rumination not only made people more depressed but also impaired their working memory.

      In a related 2008 study, psychologists Jutta Joorman and Ian Gotlib gave two groups of people a task that required them to update information continually in their working memory, as well as trying to inhibit words with negative connotations. One group of participants was suffering from depression and the other was not. They found that the depressed individuals had more difficulty in not mulling over negative words, which inhibited their working memory.

      We wanted to investigate these links ourselves, so we spent three months researching a group of more than one hundred twenty-somethings. We chose people in their twenties because these are the years in which people tend to move out of their parents’ home, make new friends, and explore new ideas, and though this transition into adulthood can be exciting, it can also be a stressful time and result in a sense of feeling overwhelmed and even depressed. Because this age group faces so many challenges to their happiness, they presented a good opportunity for us to explore how working memory helps us to manage our emotions and stay positive.

      The twenty-somethings in our study performed several cognitive tasks. First, they completed a working memory task from Tracy’s Alloway Working Memory Assessment (AWMA). We asked them questions such as, “Oranges live in water. True or false?” and then asked them to repeat the last word of the statement. Questions like this engage working memory because the brain is forced to hold the sentence in mind and decide if it’s a true statement while repeating the last word. We then divided the participants into those with strong and weak working memory.

      We also asked these young adults to complete questionnaires often used in hospitals and clinics to provide an objective measure of depression. This required participants to rate statements depending on how strongly they felt each applied to them during the past week. Some statements expressed negative feelings such as, “I was bothered by things that don’t usually bother me.” Others expressed positive feelings such as, “I felt hopeful about the future.” Based on their responses, we determined whether they were depressed. We also measured their tendency for rumination using a similar questionnaire.

      We had hypothesized that ruminators and depressed participants would have relatively poor working memory and that ruminators would be depressed. But when we analyzed the working memory scores, СКАЧАТЬ