Newsletter #283: The Quiet Toll of Multitasking & Interruptions
This week, I'd like to talk about multitasking.
Actually, if you stop and think about it, the very term "multitasking" is kind of misleading.
You see, multitasking implies that you're doing more than one thing at once, but that's typically not what's actually going on. You're really switching back and forth between multiple activities, which is why researchers in this field refer to this behavior as "task-switching."
An abundance of experimental evidence has revealed that when you are switching back and forth between two different activities, your performance on both tasks tends to fall off a cliff. As one researcher put it, "The illusion of productivity comes at the expense of performance effectiveness."
But to be fair, the very nature of modern life makes concentrating on one thing rather difficult, and this is true even at work when we want to be able to stay focused. That’s because we are constantly bombarded with interruptions – both external and self-imposed.
What impact does this have on our productivity, over the course of a day? And how might this influence our health, over the long haul?
This Week’s Research Highlights
In a previous study, researchers at UC Irvine found that information workers switched between different tasks at an astounding frequency, on average every three minutes. To gain in-depth insight into why and how this sort of work fragmentation occurs, researchers conducted a field study at an outsourcing company providing information technology and accounting services for major financial bond management companies. There, they were able to closely monitor the day-to-day activities of a range of workers, including software developers, financial analysts, and managers. The researchers shadowed 24 workers for a total of 700 formal hours of observation, with long interviews conducted afterwards to discuss their activities and clarify their observations. All activities were carefully documented and timestamped.
So what do they find?
Well, these folks seemed to get interrupted a lot, in line with prior research. Nearly 60% of all tasks were interrupted, and the average length of time that a worker spent on a given task, before being interrupted or switching to something else, was just 11 min and 4 sec.
Then the researchers analyzed how this interrupted work was resumed, and that is where the true cost is revealed. Now, most of the time, the workers were able to resume their interrupted tasks on the same day. When they did, it took on average 25 minutes to return to that task. But what really makes this troublesome is that they worked on at least two other activities, on average, before finally getting back around to the original task, and the participants reported that this sort of juggling act was particularly detrimental to their productivity.
This makes sense. Following these sorts of interruptions, you have to expend some of your finite cognitive resources to reorient yourself to what you were doing before. You might have to restructure the environment to find your way back to where you were, like re-opening a document that you closed, switching to different tabs on your browser, etc. This leads to disproportionate delays following what probably should be relatively brief interruptions.
Importantly, the cognitive load associated with all of these interruptions may also leave a physical mark, which is what we'll address next.
Stress associated with work can have devastating health consequences. For instance, a study that followed healthy workers at a large Finnish company for more than 25 years who did not have cardiovascular disease at the start of the study found that employees who dealt with high job strain had a 2.2-fold higher risk of going on to die from heart disease. This is because stress is not merely a mental phenomenon – stress activates the hypothalamic-pituitary-adrenal (HPA) axis, eliciting a host of physiological responses through the associated hormonal cascade.
To examine how exposure to interruptions affects physiological stress, researchers in Zürich remodeled their lab into a group office environment, and assigned 90 participants to workstations equipped with desks and computers. They were instructed to perform typical office tasks, like typing up information from hand-written forms and arranging appointments with simulated clients. While they did so, the researchers measured their heartbeat and took saliva samples to measure levels of cortisol at various points.
Partway through the experiment, the participants were compelled to compete for a fictional promotion – a challenge which was designed to elicit stress. For some of them, they were allowed to focus on the task at hand, but others had to deal with this while also fielding ongoing interruptions, in the form of text messages from superiors.
The contrived competition served its purpose, elevating heart rate and cortisol levels in all participants. However, those who were being interrupted with messages released almost twice as much cortisol.
Interestingly, despite exhibiting greater physiological stress, they didn’t report experiencing greater subjective stress than their uninterrupted counterparts. I suppose it illustrates that you can be under a lot of strain, and even pay a price biologically, but not necessarily be conscious of it.
Random Trivia & Weird News
There is a long-standing stereotype that women are superior multitaskers, probably emanating from traditional gender roles. Alas, research has not borne this out.
A team of researchers in Amsterdam put participants through a computerized simulation where they had to perform a series of tasks according to one of three possible schedules: 1) sequentially; 2) forced to multitask; or 3) free to organize the work as they saw fit.
Unsurprisingly, those who performed the work sequentially did better than those who were forced to multitask, and the researchers found there was no sex difference in multitasking ability. As it turns out, most of us suck pretty equally at it.
Podcasts We Loved This Week
- Edward Calabrese: The hormesis revolution in biology, neuroscience, and medicine. Via Brain Ponderings.
- Greg Potter: How to align your circadian rhythms for better health and performance. Via Reason & Wellbeing.
Products We Like
The Pomodoro technique is a time-management method that divides your work time into 25-minute blocks, separated with 3-5 minutes of rest time in between each bout. The goal of this system is to prevent internal and external interruptions from disrupting focus and flow, while also avoiding risk of fatigue and burnout. This was traditionally achieved using a tomato-shaped kitchen timer (hence the name — pomodoro is Italian for tomato). It’s a very simple app with a clean interface, and you can either use it on desktop, or mobile app (App Store or Google Play). If you are having a hard time concentrating on projects and would like to structure your time better, it is worth a shot.
humanOS Catalog Feature of the Week
This week, we’d like to highlight one of the lessons from our Daily Performance and Stress course.
This lesson addresses the somewhat complicated relationship between stress and our brain performance. It is theorized that we perform best at a certain optimal level of arousal, which is represented by a bell-shaped curve.
When stress is too low, we’re bored and disengaged, and lack the urgency to get stuff done. On the other hand, as we’ve seen from the research described above, when levels of stress are too high, performance tends to decline. How does stress affect the brain? And how can we intelligently harness stress so it works for us, instead of against us?