(female professor) So, we\\\'ve been talking about how different areas of the brain are activated when we process information, right?So, let\'s think about all the things you\'re doing right now.Really, you should only be focusing on my lecture, but I\'m sure a few of you are also engaged in some other activity.Maybe you\'re checking email or sending a text message to a friend. Almost all of us do this type of media multitasking to some extent. It\'s really become the norm.And yet, as you already know, from your reading, the brain isn\'t suited to processing very many demands at once.If you\'ll recall, we read about an experiment that tested people\'s abilities to complete up to three mental tasks simultaneously.The study showed that there was brain activity in both frontal lobes when a person was focused on only one task.When a person took on a second task, the frontal lobes divided their responsibilities. Each lobe could process one task.But when a third task was added, one of the original tasks disappeared from the brain.So that indicates that the brain can really only focus on two activities at a time at most.Well, now I wanna talk about some research by a psychologist named Clifford Nass that compares the cognitive performance of heavy and light, medium multitaskers.Nass looked at the way these 2 groups of people performed on a series of tasks. And he found several cognitive differences between the groups.The first difference had to do with the cognitive function called filtering, which for our purposes today means, well, it refers to the ability to distinguish between relevant and irrelevant information.Someone who\'s good at filtering should be able to focus on the task at hand.What the study found was that people who regularly engage in heavy multitasking are pretty easily distracted, and the greater the quantity of irrelevant information that\'s presented, the more likely they\'ll become sidetracked from what they\'re supposed to be doing.In addition to filtering, the study also measured the ability to manage working memory.Working memory is what allows you to remember and use information for a short period of time.Um. For instance, working memory is what allows you to hold a phone number in your head and dial it at the same time.The way Nass described it, he, um, compared working memory to a filing cabinet. Only you\'ll have to think of it as a cabinet of temporary files.Just like organized office workers can quickly find what they need in their filing cabinet.People with good working memory can retrieve the information they need pretty easily.Heavy multitaskers were found to be really bad at this. All of their files are in disarray, so to speak.And finally, um, Nass was also looking at the 2 groups ability to switch over from working on one task, to working on another.Were heavy multitaskers skillful at this? No, it appears they turned out to be much slower at switching tasks than light multitaskers.So, in summary, well, Nass basically found that heavy multitaskers were the weakest in all three of the skills that were being studied.In fact, they seem to be worse at multitasking than the light multitaskers are.And I have to say the finding I consider astonishing was that heavy multitaskers had no idea that they were so bad at multitasking.Anyhow, that set of three skills is what we call cognitive control.So there appears to be some correlation between heavy multitasking and lower cognitive control.One question that\'s been asked since the study is: which causes which?Is heavy multitasking responsible for lowering cognitive control? Or are people with low cognitive control just especially attracted to multitasking?Frankly, it might not really matter which way the causation goes.I mean if it\'s heavy multitasking that\'s the cause then obviously cutting back on that behavior would be beneficial.Likewise, if, instead, it\'s low cognitive control that attracts people to heavy multitasking, it\'s probably still beneficial to cut back.Because in that scenario, those with the least ability to deal with multiple sources of information are exposing themselves to the highest levels of input.Well, I don\'t know. Cutting back sounds good in theory, doesn\'t it?But how many people are willing to cut back on our television, computers, cell phones once we\'ve gotten used to them?I\'m afraid it\'s hard. Even for those of us who know better.