Читать книгу The New IQ: Use Your Working Memory to Think Stronger, Smarter, Faster - Tracy Alloway - Страница 41

The ability to focus is another advantage that working memory gives us. Focus is crucial to learning and makes a big difference in our performance in school and beyond. In order to focus, your Conductor has to keep the goal in mind while making sure no other distracting thoughts overwhelm you. This is, of course, increasingly challenging in the world of nonstop email, Twitter feeds, and multiple windows open on our computers.

The fact that the strength of one’s working memory makes a great deal of difference in this skill was demonstrated powerfully in a study that Michael Kane and colleagues at the University of North Carolina conducted in 2007, which measured the impact of working memory on people’s ability to stay on task in the midst of demanding activities. They gave working memory tests to more than one hundred young adults and asked them to keep a week-long record detailing how often they experienced distracting thoughts or mind wandering. They found that the people with low working memory scores were often distracted, especially as the tasks got harder. In contrast, those with high working memory scores maintained their attention better.

Distraction isn’t the only impediment to focus. We are all increasingly expected to multitask, and studies have shown that this demand to multitask taxes working memory and easily overwhelms it.

Let’s take a look at what multitasking might look like in the brain. Imagine that it is seven o’clock on a Wednesday night, and you are helping your daughter, Gemma, with her long-division homework. The last time you did long division was twenty-five years ago, so it’s not an easy chore, and you are firing signals between your intraparietal sulcus and PFC to stay on top of things.

All of a sudden, you hear your phone make the email “ding!” and you break your attention from long division. You have a big deal in your sights at work, and they need your help. You’ve got to respond with some critical information ASAP. You set aside the long division, and fire off a quick response. Now, back to the long division.

Psychologists call this skill task switching, and it is closely connected to your working memory abilities, as a colleague at the University of Geneva, Pierre Barrouillet, discovered in 2008. Barrouillet wanted to find out how switching from one task to another affects working memory. He gave the participants number tasks on a computer screen. Numbers were colored red and blue according to the task the person had to do. In the red task, participants had to decide whether numbers were larger or smaller than five. In the blue task, participants had to judge whether numbers were odd or even. The participants were given a chance to try it out and become used to the rules of both tasks.

Barrouillet could now test whether switching between the red task and the blue task would jeopardize performance. When the participants had to do only the red task, they were fine. But when they had to quickly switch between the red and blue tasks, their working memory was overwhelmed. It took them much longer to complete it, and they also made more errors.

One of the hardest realities of life these days is that there are certain times when you simply can’t shift your attention from one task fully to the other but must do both at once. For example, you may find yourself having to answer an email from work while sitting in a meeting with your child’s teacher, or take a call from school while navigating the highway on-ramp on your way to work. Can working memory allow us to do both, and will we be able to perform both tasks just as well as if we were focusing our attention on only one task? It depends.

In 2010, Jason Watson and David Strayer at the University of Utah tested the ability of two hundred people to handle a multitude of tasks. The participants had to drive in a simulator while using a hands-free phone. To make the task even more challenging, they had to listen to an audio of a series of words interspersed with math problems. This was a working memory task that required considerable mental agility: they had to use their working memory to retrieve mathematical information from their long-term library to solve a problem. At the same time, they had to keep track of a string of words in the correct order. On top of all this, they had to negotiate traffic in the simulator.

Out of the two hundred adults, the majority of them did worse in the driving simulator when they had to use their working memory at the same time. They took longer to brake than they should, and they tailgated a pace car. If you ever had to think through a work problem while driving or even decode your Aunt Mabel’s cryptic and hastily scribbled directions in the days before GPS, you know your driving can suffer. The results of this experiment were clear: people perform worse when they have to do more than one task at the same time. Watson and Strayer also found that while most people are at least able to keep two possible tasks in their mind, when that number grows and they are forced to handle more than two tasks, their working memory Conductor drops the baton.

Scientists have known since the 1980s that performing two tasks at the same time undermines performance in both. But one additional discovery Watson and Strayer made was quite surprising: the rule that performing two tasks at once undermines our ability to do each well doesn’t apply to all of us. Participants who had top working memory scores were able to do both the driving and the working memory task at the same time without any decline in the performance of either. For these “Super Taskers,” as Watson and Strayer call them, their working memory was so good that it took everything in stride. If we improve our working memory, we can become more like the supertaskers.