The Negative Effects of Multitasking

2018-05-10

It’s a phrase that often appears on a job seeker’s resume: ‘excellent multitasker’. As so many of us list it among our professional skills, the ability to multitask is thought to be an asset. But what if tackling several tasks at once not only makes us less effective, it actually has a negative effect on cognitive function? New research has indicated that this may be true.

Business owners, professionals and parents are just a few examples of people who are wired to “do it all” – and often, this means doing it all at once. The modern world has created an expectation that adults be available by mobile phone, email or text message at any given moment. An article in The Guardian notes that in previous decades, it was normal to be unreachable at times throughout the day – sometimes, you were away from your home or office and would have to reply to messages later. Now, professionals may answer their phones mid-meeting to tell the caller they’re “in a meeting” – essentially asking forgiveness for not being immediately available. This is something that would have been unheard of in a professional setting decades ago. As the article notes, technology and the subsequent work culture “has created an implicit expectation that you should be able to reach someone when it is convenient for you, regardless of whether it is convenient for them.”1

This has led to a society of workers who are tackling multiple projects while fielding calls, emails and other intrusions throughout the day. It may feel like a lot is getting done, but in truth, this approach can slow individuals down more than it speeds them up. Neuroscientist Daniel J. Levitin explains, “Multitasking has been found to increase the production of the stress hormone cortisol as well as the fight-or-flight hormone adrenaline, which can overstimulate your brain and cause mental fog or scrambled thinking. [It] creates a dopamine-addiction feedback loop, effectively rewarding the brain for losing focus and for constantly searching for external stimulation.”2

Furthermore, the same article explains that the prefrontal cortex has a novelty bias, which means it’s easy to fall off task when a new or more interesting stimulus is introduced (essentially, a “shiny object” that distracts us). While professionals may feel able to focus while flipping between projects, it’s likely the end result or timeline suffers.

The effect of info-mania

This explains why multitasking can have a negative effect on our ability to produce quality work. However, psychology professor Glenn Wilson asserts that this “info-mania” creates measurable decline in our cognitive abilities. The distraction of unread email in a person’s inbox can impair their function by around 10% – more dramatic than the effect of marijuana use, he claims.3 A neuroscientist at Standard, Russ Poldrack, adds that multitasking can cause information to go to the wrong part of your brain. Even studying (or working) with the television on nearby can cause information to be stored in the striatum instead of the hippocampus (information is more easily organized and retrieved by the latter).4

It’s not just multitasking, one researcher states – it’s too much information everywhere. In an age where professionals are bombarded with both private and public information, decisions can be clouded by having more detail than is needed. Essentially, our brains go into overdrive and can be influenced by facts we didn’t ask for.5 Even when focused on a single idea or decision, an overage of information may be causing our brains to multitask.

The power of single-tasking

Working on many projects at once may feel effective, but it’s generally an illusion. As researchers at MIT have found, multitasking actually ruins productivity, causes mistakes and impedes creative thought.6 To make the most of your working hours, try blocking off time for specific tasks and focusing on one thing at a time. This may mean setting your phone aside or closing your inbox for a period of time. Not only will this allow you to work more effectively, it is better for your cognitive function and overall health.


1 Why the modern world is bad for your brain (The Guardian) https://www.theguardian.com/science/2015/jan/18/modern-world-bad-for-brain-daniel-j-levitin-organized-mind-information-overload
2 https://www.theguardian.com/science/2015/jan/18/modern-world-bad-for-brain-daniel-j-levitin-organized-mind-information-overload
3 https://www.theguardian.com/science/2015/jan/18/modern-world-bad-for-brain-daniel-j-levitin-organized-mind-information-overload
4 https://www.theguardian.com/science/2015/jan/18/modern-world-bad-for-brain-daniel-j-levitin-organized-mind-information-overload
5 Too Much Information (Fast Company) https://www.fastcompany.com/45655/too-much-information
6 Why You Shouldn’t Multitask (Fortune) http://fortune.com/2016/12/07/why-you-shouldnt-multitask/