The True Cost of Multi-tasking

Picture of a sunset over water
My view last week “off the grid”

I spent last week “off the grid” on an island in Lake Michigan.  No internet, no email, no cell phones. It was different, interesting, and strange. I was actually glad to get back to the grid. But the experience made me think. The major difference for me was that I stopped “multi-tasking”.

Task switching, not multi-tasking —  A while ago I wrote a post about multi-tasking, and the research at Stanford that shows that even younger people aren’t good at multi-tasking.  But the term multi-tasking is actually a misnomer. People can’t actually do more than one task at a time. Instead we switch tasks. So the term that is used in the research is “task switching”.

Task switching is “expensive” — There has been a lot of research on task switching. Here’s what we know from the research:

  • It takes more time to get tasks completed if you switch between them than if you do them one at a time.
  • You make more errors when you switch than if you do one task at a time.
  • If the tasks are complex then these time and error penalties increase.
  • Each task switch might waste only 1/10th of a second, but if you do a lot of switching in a day it can add up to a loss of 40% of your productivity.
  • Task switching involves several parts of your brain: Brain scans during task switching show activity in four major areas: the pre-frontal cortex is involved in shifting and focusing your attention, and selecting which task to do when. The posterior parietal lobe activates rules for each task you switch to, the anterior cingulate gyrus monitors errors, and the pre-motor cortex is preparing for you to move in some way.
Does having more communication channels encourage task switching? When I was off the grid I found that I started doing one task at a time. I would do one thing for several minutes, and in many cases several hours. I believe that being online encourages task switching. When you can go from email to chat to texting to twitter to phone to facebook you switch tasks more. When I was off the grid all my channels were gone. So instead I spent time with one task and with one program. One day I worked in IPhoto for 3 hours straight.
Additional costs– One last insight from my week off the grid: I was much less agitated. It’s my hypothesis that task switching not only wastes time and increases errors. Task switching causes fatigue, exhaustion and agitation.
Less task switching = more happiness? — Now that I am back on the grid I wonder if I can break the task switching addiction and improve my mood, energy, happiness, productivity, and error rate? Can I beat the task switching habit?
What do you think? Have you been able to do less task switching? Have you tried?
And for those of you who like to check out the research:

Meyer, D. E., Evans, J. E., Lauber, E. J., Gmeindl, L., Rubinstein, J., Junck, L., & Koeppe, R. A. (1998). The role of dorsolateral prefrontal cortex for executive cognitive processes in task switching. Journal of Cognitive Neuroscience, 1998, Vol. 10.

100 Things You Should Know About People: #100 — Sustained Attention Lasts 10 Minutes

chart showing drop in attention after 10 minutes
After 10 Minutes Attention Wanes

You are sitting in a meeting, and someone is presenting sales figures for last quarter. How long can this person hold your attention?

7-10 — If the topic is of interest to you, and the person is a good presenter, the maximum you can focus on the presentation is about 7-10 minutes. And if you are not interested in the topic and/or the presenter is particularly boring, then you’ll lose interest much faster. For most people performing most tasks, they can hold attention for 7 to 10 minutes, and then the attention will start to wane.

Break buys you another 7-10 — People can take a short break and then start over with another 7 to 10 minutes period, but 7 to 10 minutes is about how long they can pay attention to one task.

The end of a journey — For those of you who have been following my series, “100 Things You Should Know About People”, you probably realized that with this post I have reached the end of my 100 Things. Stay tuned for what comes next!

 

100 Things You Should Know About People: #98 — Attention Is Selective

In the paragraph below, read only the words that are bold, and ignore all the other text.

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Filtering out stimuli — In many situations people get easily distracted. In fact, you can often grab people’s attention away from what they are focusing on. But it is also possible for people to pay attention to one thing and filter out all other stimuli. This is called selective attention.

Unconscious selective attention — You are walking down a path in the woods, thinking about an upcoming business trip you are taking, and you see a snake on the ground. You freeze and jump backwards. Your heart starts racing. You are ready to run away. But wait, it’s not a snake. It’s just a stick. You calm down and keep walking on the path. You noticed the stick, and even responded to it, in a largely unconscious way.My book,  Neuro Web Design: What makes them click, is all about unconscious mental processing. Some of the time you are aware of your conscious selective attention, for example, when you were reading the paragraph at the beginning of the chapter. But there is also a lot of selective attention that operates unconsciously.

What do you think? How good are you at selective attention?

100 Things You Should Know About People: #97 — People Filter Information

Have you ever met someone that has a long held belief that they just won’t change, no matter how much evidence you show them that their belief is not tenable? People seek out and pay attention to information and cues that confirm the beliefs that they have. They don’t seek out, in fact they ignore, or even discount, information that doesn’t support what they already believe.

Photo of military personnel in a control room
USS Vincennes

Useful strategy or bad idea? — Filtering is often a useful strategy, since it reduces the amount of information that you have to pay attention to at any one time. But sometimes filtering can lead to bad choices.

Shooting down a commercial jet — In 1988 the US Navy had a ship in the Persian gulf called the USS Vincennes. One day, while scanning the radar on the screen on the ship, the crew saw aircraft headed their way. They decided early on that the approaching aircraft was not a commercial airliner, but a hostile military plane. They shot down the plane, which did turn out to be a commercial airliner with 290 passengers and crew. Everyone died.

Many factors led to this erroneous conclusion — The situation was stressful , and the room was too dark. There were many unclear or ambiguous pieces of information that made it hard for the crew to understand what they were looking at on their screen. Most significant, however, in the incident, is what they chose to pay attention to and what they chose to ignore.

The crew filtered — Several crew members were convinced from the start that it was a hostile military plane, and from that point on they filtered all the information coming in. The crew had rehearsed the a training scenario many times on what to do when there is a hostile military plane in their air space. They ignored evidence that it was, in fact, a commercial plane, paid attention only to the information that led them to think it was a hostile military craft, and then proceeded to carry out the training scenario. All leading them to an incorrect resolution.

What do you think? Are you aware when you are filtering?

100 Things You Should Know About People: #58 — People See What They Expect To See

Picture from airport xray machine
Why do airport screeners miss guns in carry-ons?

During December of 2009, Farid Seif, a businessman from Houston, Texas, boarded a flight in Houston with a loaded handgun in his laptop case. He made it through security without a problem. Farid is not a terrorist. The gun is legal in Texas; he forgot to take it out of his laptop case before his travel. Farid realized the mistake when he got to his destination at the end of the trip.

Airport security at the Houston airport did not detect the gun. It would have been easily seen by a security screener through the scanner at the airport, but no one noticed it.

Homeland Security in the US routinely tests the ability to pass security screening with guns, bomb parts, and other forbidden materials, by sending people through undercover with material. The US government hasn’t released the figures officially, but the estimate is that 70% of these tests fail, meaning most of the time the undercover people are able to get through security, like Farid Seif, with objects that are supposed to be spotted.

People get used to the frequency of an event Why do the security personnel notice the bottle of shampoo that is too large, but miss a loaded handgun? Research on attention gives a hint on why this might happen. It has to do with the expectation of how frequently an event does or does not happen.

Continue reading “100 Things You Should Know About People: #58 — People See What They Expect To See”

100 Things You Should Know About People: #39 — Your Mind Wanders 30% of the Time

Photo by Dave Grave*

You are at work reading a report that one of your colleagues has written and you realize that you’ve just read the same sentence about three times. Instead of thinking about what you were reading, your mind wandered.

Mind wandering is similar to, but not the same thing as daydreaming. Psychologists use daydreaming to refer to any stray thoughts, fantasies, or stories you imagine, for example, winning the lottery, or being a famous celebrity. The term mind wandering is more specific, and refers to when you are doing one task and then fade into thinking about something that is not related to that task.

Mind wandering is a very common phenomena – We underestimate our mind wandering; according to Jonathan Schooler of UC, Santa Barbara, we think our minds are wandering about 10% of the time, when it is actually much more. In normal every day activities our mind is wandering up to 30% of the time, and in some cases, for instance when driving on an uncrowded highway, it might be as high as 70%.

Wandering minds annoy some neuroscientists – Some neuroscientists became interested in studying wandering minds because they were such an annoyance while doing brain scan research. The researchers would have subjects do a certain task, for example, look at a picture, or read a passage, while scanning for brain activity. About 30% of the time they would get extraneous results which did not seem to be related to the task at hand. That’s because the subject’s mind was wandering from the task at hand. Eventually the researchers decided to start studying the wandering rather than just getting annoyed by it.

Why a wandering mind can be a good thing – Mind wandering allows one part of the brain to focus on the task at hand, and another part of the brain to keep a higher goal in mind. So you are driving and paying attention to the road, but you are also thinking about when you should stop for gas. Or you are reading an article online about a thyroid medication called Synthroid that your doctor thinks you should take, but your mind wanders to the idea that you should put that salon appointment on your calendar. Mind wandering might be the closest thing we have to multi-tasking. It’s not really multi-tasking, (which doesn’t exist…you can see my previous blog post on that), but mind wandering does allow you to keep important goals in mind while doing one thing.

Why a wandering mind can be a bad thing – Much of the time when our mind wanders we aren’t aware of it. More “zoning out” than “mind wandering”, this means that we can miss important information. For example, if you are supposed to be reading that report from your colleague, but you are instead thinking about what to make for dinner, that may just mean you are being unproductive. We aren’t usually aware when we are zoning out.

More mind wandering = more creativity – The researchers at UC, Santa Barbara have evidence that people whose mind wanders a lot are more creative and better problem solvers. Their brains have them working on the task at hand, but simultaneously processing other information, and making connections.

Mind wandering and the internet – I’ve been thinking about the fact that the ability to quickly switch from topic to topic is what the web does really well.  Is web surfing related to mind wandering? Here are some of my mind wanderings on this topic:

  • Do we like web surfing because it enables this type of wandering?
  • Rather than designing web sites to try and hold people’s attention should we design to encourage wandering?
  • Should we build in feedback about the wandering so that it is easier to get people back to the original thought?

What do you think?

If you like to read research:

Christoff, et. al., Experience sampling during fMRI reveals default network and executive system contributions to mind wandering. Proceedings of the National Academy of the Sciences, May 11, 2009.

Mason, et. al., Wandering Minds: The default network and stimulus-independent thought. Science, January 19, 2007.

Photo Credit: : http://www.flickr.com/photos/daveograve/

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100 Things You Should Know About People: #20 — Your Attention Is Riveted By Pictures Of People

Picture of a baby looking right at the camera Second only to movement (animation, video), pictures of a human face capture attention in any medium, including websites. Pictures of a human face not only capture attention, but keep the attention on that part of the screen even when the picture goes away.

We start young — With some creative experiments it has been proven that babies as young as 4 months old will look at pictures of other people more than pictures of other objects or of animals. And this preference for faces continues throughout the life span. It seems to be part of our brain wiring.

The eyes have it — Research using eye tracking shows that when you show people a picture of the face of a person, their attention goes mostly to the eyes. If you want to capture someone’s attention at a website, showing a picture of a person who is looking right into the camera captures the most attention. Continue reading “100 Things You Should Know About People: #20 — Your Attention Is Riveted By Pictures Of People”

100 Things You Should Know About People: #18 — What People Look At On a Picture Or Screen Depends On What You Say To Them

Yarbus Eye Tracking Picture
Yarbus Eye Tracking Picture

Eye tracking is a technology that allows you to see and record what a person is looking at, and for how long. One way it is used is to study web sites to see where people are looking on a web page, where they look first, second, etc. It’s a pretty interesting technology, one of the benefits being that you don’t have to rely on what people SAY they are looking at, but can collect the data directly. Like any technology, however, it’s not perfect, and one of the problems with eye tracking is that you can’t just give people a web site to look at and then assume that where they look is what they are “really interested” in.

We underestimate the effect our instructions have on where someone looks. Look at the picture at the beginning of this post. In research by Yarbus, people were shown this picture, and then given different instructions of what to think about while looking at the picture. Below are the eye gaze patterns matched with the instructions that people were given: Continue reading “100 Things You Should Know About People: #18 — What People Look At On a Picture Or Screen Depends On What You Say To Them”

100 Things You Should Know About People: #11 — Why You Can't Resist Paying Attention to Food, Sex, or Danger

burgersmall
Food Captures Attention

Have you ever wondered why traffic always slows when people are driving by an accident? Do you moan about the fact that people are attracted by the gruesome, and yet find that you glance over too as you drive by? Well, it’s not really your fault, you (and everybody else) can’t resist looking at scenes of danger. It’s your “old brain” telling you to PAY ATTENTION.

You have 3 brains — In my book, Neuro Web Design: What makes them click? I talk about the idea that you really don’t have one brain, you have three. The “new brain” is the conscious, reasoning, logical brain that you think you know best; the mid brain” is the part of the brain that processes emotions, and the “old brain” is the part of the brain that is most interested in your survival.

From reptiles to people — If you look at brains from an evolutionary perspective, the “old brain” developed first (hence the name “old brain”!). In fact, that part of our brain is very similar to the brain of a reptile, which is why some people call it the “reptilian” brain. Continue reading “100 Things You Should Know About People: #11 — Why You Can't Resist Paying Attention to Food, Sex, or Danger”

100 Things You Should Know about People: #1– You Have "Inattention Blindness"

I’ve decided to start a series called 100 Things You Should Know about People. As in: 100 things you should know if you are going to design an effective and persuasive website, web application or software application. Or maybe just 100 things that everyone should know about humans!

The order that I’ll present these 100 things is going to be pretty random. So the fact that this first one is first doesn’t mean that’s it’s the most important.. just that it came to mind first.

I hope you enjoy this series. Make sure to let me know by posting comments.

So here’s #1 — Inattention Blindness

First let’s start with a little test for you to take. Watch the video below:

This is an example of what is called “inattention blindness” or “change blindness”. The idea is that people often miss large changes in their visual field. This has been shown in many experiments. Here is a description of an experiment conducted outside the lab:

So what does this mean if you are designing a website or something on a computer screen? It means that you can’t assume that just because something is on the screen means that people see it. This is especially true when you refresh a screen and make one change on it. People may not realize they are even looking at a different screen. Remember, just because something happens in the visual field doesn’t mean that people are consciously aware of it.

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