Multitasking - just because you can, does it mean you should?

So, you think you’re really good at multitasking, and that you can concentrate just as well doing more than one thing at a time?  Think again.  You may be giving the impression you are doing a lot, but the reality is often something different. Now that we have access to functional MRI scans, we can actually see, monitor and record what our brains are doing while we’re doing it. And what we now know is that multitasking could mean that you are doing nothing well enough to gain any benefit from doing it.

In an experiment carried out at the University of California, Los Angeles a group of 20-something students were asked to sort through index cards in two trials.  The first time, the students worked in silence and during the second exact same task they were asked to listen out for specific tones in a series of randomly presented sounds.  The way their brains coped with this was to transfer from the hippocampus, the part of the brain that stores and recalls information, to the striatum, which handles repetitive activities.  They had no trouble doing the same task while distracted, but they found it much more difficult afterwards to remember what, exactly, they had been sorting.  So their ability to do the task in a way that meant they later remembered what it was they were doing was compromised. What this tells us is that if you are trying to learn a new skill, you won’t do it as well, or as easily, if you are distracted while you are doing it.

The neuroplasticity of our brains means that they are built to manage a variety of tasks at once, but only up to a point.  It seems that this physiological balancing act we ask of our brains comes at a cost. By constantly switching back and forth, and by stimulating parts of the brain that are concerned with visual processing and physical co-ordination, as in the experiment described above, we appear to distract from the higher areas of the brain related to memory and learning. We can end up concentrating of the process of concentrating rather than on what we were supposed to be concentrating on!  Much of the time, it probably won’t matter much, but it’s easy to see how inefficient a way of learning it is.  Concentrate well, do it once: distract yourself and you may have to do something several times before it’s learnt. And when it comes to storing information that you want to recall later, perhaps when revising for an exam, you just won’t learn it so well if you don’t concentrate while you’re learning.  Focusing or concentrating well means that you store information in the part of the brain necessary for later recall.

True, there are some forms of multi-tasking that do work, but this usually involves only doing a maximum of two things at once, one of which is done automatically, i.e. washing-up and listening to the radio.   Washing-up doesn’t really take much thought, so 95% of your concentration can be given over to the other task in hand.  This wouldn’t apply to doing three tasks, though: washing-up, listening to the radio and reading a book.  It’s just not possible to absorb either the book or the radio adequately, so – along with the practical difficulties of doing all three at once – you probably wouldn’t bother.  

However, there are some activities that appear automatic, but actually require good concentration to be safe, as the ban on driving while simultaneously using your mobile phone now recognizes. It may appear to be an automatic skill but driving is a complex activity, requiring excellent concentration and good reaction times, both of which will be impaired if focusing on something else.  Talking on a mobile phone, while driving, is now illegal in the UK and many other countries and with good reason since fatal accidents have been the result. Many experts also believe that talking on a hands-free phone is also too distracting to be entirely safe.  “Multitasking is always going to slow you down, increasing the chances of mistakes,” says David Meyer, a cognitive scientist and Director of the Brain, Cognition and Action Laboratory at the University of Michigan, in the US.  “Disruptions and interruptions are a bad deal from the standpoint of our ability to process information.”

It is impossible to precisely measure lost productivity, caused by multi-tasking, but in 2007, Jonathan Spira, chief analyst at Basex, a business-research firm, estimated the cost of interruptions to the US economy at nearly $650 billion a year.  This figure was based on surveys and interviews with professionals and office workers, which concluded that 28% of their time was spent on what they considered to be interruptions (and recovery time) before they returned to their main tasks. Spira conceded that $650 billion is a rough estimate, and work interruptions will never, and shouldn’t be eliminated, because this is often how work is done and ideas are shared.  But even if half of all those constant interruptions at work are worthwhile, it still represents a lot of money lost,

There may also be another cost to distraction resulting from multitasking.  The process of constantly switching, multi-tasking, call it what you will, carries with it a degree of stress.  Not necessarily one that you would even notice, but one that requires the key stress hormones, (cortisol and adrenaline), to be secreted at higher levels to help you stay on top of what you are trying to do. These are the same hormones that are secreted when we need short, rapid bursts of energy necessary for ‘fight or flight’, but they are not designed for long-term use. 

In the short term, feeling constantly “hyped” by high levels of stress hormones can result in a persistent ‘brain fog’ many of us experience, and in the long-term, bombarding the brain with stress hormones that are neuro-toxic when secreted in large quantities, may cause premature ageing and other brain damage. Interestingly, cortisol is what is known as a universal donor which means it can attach to any receptor site and block the feel-good hormones, dopamine and serotonin, which help us feel calm and happy. So, not only are we stressed when we multitask, we are also missing out on the more positive effects of the body’s own, natural antidotes.  

Hyper-vigilant, over-alert and anxious, it’s hardly surprising we feel too stressed to concentrate.