Multi-tasking: the myth that is costing you.

Multi-tasking: the myth that is costing you.

5 years ago 0 0 3512

How many times do you hear about ‘multitasking’? It seems to be a concept associated with modern times, with everyone under pressure to achieve so much, all at the same time. People are on their phones, sending mails, checking social media, and attempting to do other work tasks. Or you ask your partner to do this, and do that, at the same time.

Lets test your multitasking abilities with a little exercise:

Part A: As fast as you can, write the first ten letters of the alphabet (hint: a, b, …), then immediately write the first ten numbers (hint: 1, 2….). Time how long this took you.

Part B: Now, as fast as you can, write every second letter (hint:a,c..) up to ten letters, then immediately write every third number (1,4…) up to ten numbers. Time how long this took.

Part C. This time, write every second letter then every third number, switching between letter and numbers, until 10 numbers and 10 letters are on the page. Hint (letter 1, number 1, letter 2, number 2, etc). Time yourself and see how long it takes.

Check how you went: Have a look at the three times, what did you notice? How easy or hard did you perform each of the three tasks? What else did you notice as you did this exercise?

If you are like virtually everyone else on the planet (not a letters and numbers savant, perhaps), then your times would have increased across the exercises. In part A, most people drop into a patterned response and can do the writing of the first 10 digits and letters without effort, and very fast. In Part B, people have to apply thought and effort to the list. The sequences are not common, so you have to put cognitive effort into creating them. They are still simple tasks, so the time would have gone up a bit, but for most people it is only moderately challenging.

It is part C where things get interesting. Here are two cognitive tasks (that you have already completed) that you have to rapidly switch between to get the sequence. My guess is that this took the longest time to complete, and was the most difficult and taxing of the lot, if you managed to complete it without giving up.

If multitasking had no cost, then exercise C would have been as easy as the earlier exercises, and completed as fast. Just as a quick refresher, without looking, what was the 5th Letter and 5th number from each list? (How long did it take you to get the answer?). Because rapid switching between tasks – what you have been told is ‘multitasking’ costs time, effort, cognitive capacity, focus and the ability to remember. This is all based upon the neuroscience of the processes involved.

The brain on multitasking:

Working memory is known to be able to hold 7 +/- 2 chunks of information at any one time. What gets selected into working memory is based upon actions of the lateral prefrontal cortex – if the brain thinks that incoming information is relevant, it is dehabituating (surprising), or you have been primed to pay attention to it, it is recruited from all of the other available inputs and passed to the working memory. This is why you can sit in a cafe and chat to a friend, whilst everything else that could distract you goes on around you out of your awareness. And it it also why a waiter unexpectedly dropping a plate and it smashing loudly stops all the conversations – it is unexpected and grabs attention.

The information that passes into your working memory can either be processed (cognitive effort made to think about it), rehearsed (have you ever repeated a phone number or a measurement to yourself over and over so you wouldn’t forget it?), or it simply dissolves in 0.5 seconds. So things are not retained – think about the thousands of thoughts you have every day that just pop up and fade away without you wasting time on them. Processing things in the working memory takes energy and effort, and also blocks up the working memory from working on other things at the same time.

When you are focusing on one task, these processes are all lined up around one action, and are effective. The brain does not have the capability to run this as a parallel process – it cannot do this to two different things at once, it cannot manage to process two different sets of data on different topics using different connections and rules at the same time.

This means that what we think is multitasking is actually rapid switching. In the prefrontal cortex, the focal idea (and all of its processes, habits, memories, beliefs, connections, etc) has to be ‘unloaded’, and the second idea ‘loaded’. Like loading the contents of a floppy disk onto an old computer, all of the connections and attributes of the focal idea or task have to be loaded, so the brain knows what to pay attention to, and know how to process what lands in working memory. This switching process takes time, cognitive effort, and also impacts upon the quality and retention of the outcomes of each process.

If you want a real world example of the impact of ‘multitasking’, consider something I see happening on the road every day. People checking their phones whilst they are on the freeway driving at 100 km/h. Research (see below) shows that if it takes you 1 second to stop if something jumps out in front of your car, then being drunk increases this to 1.15 seconds. Doesn’t seem like much, does it? In the US, this equates to about an additional 275, 000 car smashes per year. If we take what we know about multitasking, the time cost of multitasking (switching between mobile phone use and driving), the reaction time increases to 1.30 seconds – that is, twice the increase that being drunk provides. This is estimated to cause 1.6 Million car accidents in the US per year. Even if you think you can, using your mobile phone and concentrating on the road requires rapid shifts in attention, with the lag time (and cognitive cost) leading to massively increased risk.

Think about all of the other ‘multitasking moments’ that happen whilst you are trying to perform: your phone ‘pings’ when you are in a meeting. An email notification pops up whilst you are crunching numbers on a spreadsheet. You just want to check the football score whilst you are writing a big report. You do your homework in front of the newest Game of Thrones episode.

In every case, the cost is large. The more times that you rapidly switch, the greater the overall cost. It gets cognitively tiring to continually switch between 2, 3 or more tasks. It takes time. It also impacts on how you process the information. Often, the rapid switching means that the deeper memory processes and learning (associated with the hippocampus) don’t get the chance to do their thing, and the work done on the idea no longer is stored in working memory either. So it means that ideas are poorly remembered, and have to be reconstructed when the topic is ‘switched back on’ – taking more time and effort to get back to simply where you were before.

What can you do?

If the task is important, or requires cognitive effort, then focus. Remove things that could distract (surprise) you, and set yourself time to work on the issue or problem at hand.

Get in the habit of prioritising tasks, Since you cannot do things in parallel, work out the best way to be a ‘serial processor’ – one thing at a time.

If you have to switch tasks, take a moment to ‘close off’ your thinking. Take a note, commit an idea to memory, be clear on where you got up to.

Recognise that rapid switching has an energy cost, and you will get tired much more rapidly. If you have to ‘multitask’, build in better breaks to rest your brain.

Don’t use your phone in the car to check emails or texts whilst you are driving. Ever.

When you want someone to learn something, don’t hop from one idea to another. Lock each idea in in a stepwise manner, get them to commit it to memory, and then move on. Help people focus on one thing at a time to help them engage fully with it.

Where possible, ban phones from meetings. Laptops too. Meet for half the time, twice as focussed, and get more than the outcome you get if everyone is distracted and multitasking.

Note surprises and distractions, then consciously choose what you want to focus on. Don’t allow yourself to get drawn off into other people’s dramas when you want to (or need to) think about something else for yourself. Make the choice of where you direct your thinking based upon your goals, outcomes, and its value.

In the end, you control what you think about, what you allow to distract you, and how you manage your time and efforts. Notice when you want to multitask, and when it would be better to just focus in on this task, now, and use your time and thinking wisely.

If you want to know more, or how to better apply these ideas to your experience, contact now.

Leung, S., Croft, R. J., Jackson, M. L., Howard, M. E., & McKenzie, R. J. (2012). A comparison of the effect of mobile phone use and alcohol consumption on driving simulation performance. Traffic injury prevention, 13(6), 566-574.

Caird, J. K., Johnston, K. A., Willness, C. R., Asbridge, M., & Steel, P. (2014). A meta-analysis of the effects of texting on driving. Accident Analysis & Prevention, 71, 311-318.

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