We talk on the phone while we download the e-mail and remove unwanted messages and we take note of that urgent task just arisen. While we’re leaving the workplace we keep an eye on the phone and we drive thinking about the shopping list…
This is the ordinary madness of a life in multitasking, what has become the daily life of a growing number of people who move easily on multiple fronts. But everything seems to indicate that this “ease” and the apparent ability to handle different tasks at the same time, end up presenting us a high bill, and our brain is that it will pay the price.
Sharing our attention, we sacrifice details and memory
A study conducted at the University of Los Angeles reveals that multitasking, understood as the use of our mental resources in more than one activity at a time, compromises our cognitive functions.
The experiment was attended by 192 people, who had to remember as many words as possible from those that appeared on a screen. Some could focus exclusively on this task, others could listen to music and a third group had also to press a button when they heard three odd numbers in sequence.
To add an extra dose of complexity, every word that appeared on the screen was accompanied by a number. It would have been ideal if the participants could have remembered at least those words that had a higher score. The results showed that having to perform two tasks at the same time (remembering the words and indicating the odd numbers) worsens significantly the memory.
The problem is that, when we divide our attention to perform different tasks, although we retain the ability to focus on the most relevant, we are not able to catch the details. There is no doubt that this ability is important in a world characterized by constant distractions, but we cannot forget that we have limited cognitive capacity, so if we have to face a complex task, it is better to avoid any kind of distraction.
When multitasking becomes a habit, gray matter is reduced
To perform several tasks at the same time, we must be able to quickly change goals and activate different cognitive models, a process that is not too heavy for the brain itself, but can become dangerous if it is prolonged and becomes the norm.
In other words, one thing is to force our brains from time to time to manage different activities together and another to constantly live in multitasking. In this case, the opening of several fronts can have negative effects on our performance: it decreases creativity, facilitates distraction and affects productivity.
A study conducted at University College London with 75 people, revealed that the density of gray matter in some areas of the brain is reduced in those who are used to using various digital devices to do different things more or less simultaneously.
These neuroscientists analyzed the participants’ digital consumption habits and their personality characteristics, and submitted them to a voxel-based morphometry test to detect focal differences in brain anatomy. They discovered that those who had made of technological multitasking a habit, showed a lower density of gray matter in the anterior cingulated cortex, an area that not only intervenes in the control of some autonomous functions of the organism but also in the decision-making process, verbal inhibition, empathy and emotions. Furthermore, these people also achieved lower scores in cognitive control tests and emotional management.
If this were not enough, it was also found that multitasking increases the level of cortisol, the stress hormone, which can end up causing the death of neurons when it is maintained at high levels for a long period of time.
Multitasking makes us take more impulsive decisions
To put things worse, it was also appreciated that many of the decisions we make when we are immersed in multitasking are more impulsive, which leads us to make more mistakes.
A study conducted at the National Chengchi University revealed that when we are immersed in technological multitasking, for example, we show the tendency to impulsive buying, and then we repent of that purchase. This is because when we do too many things together, our prefrontal cortex is not able to adequately evaluate the pros and cons, so we act impulsively.
In fact, another research conducted with 1,100 people at the Institute of Psychiatry of the University of London revealed that multitasking can reduce our IQ by 10 points.
Add to this is that this rapid and continuous change of attention from one activity to another causes that our brain consume more energy, so we will feel more tired in less time and will also be more inclined to have a “blackout”; that is, moments when we feel exhausted or lacks of memory that prevent us from remembering what we did only a few minutes before.
The problem is that executive control functions, such as decision making, go through two different but complementary phases. In the first phase there is a change of objective, it is when we say to ourselves: “I will do this instead of that”. In the other phase, we activate the necessary rules, we disconnect from what we were doing to connect with what we will do.
Both phases allow us to switch from one task to another almost without realizing it, but if we do it too quickly, the moment will come when these stages come into conflict and our brain becomes saturated. Then “blackout” occurs. In fact, if you experience something like that often, it’s a sign that your brain is sending you to tell you that you need to slow down.
So, now you know it: you have to reduce the pace and focus only on one thing at a time. You will be more productive and your brain will thank you.
Sources:
Middlebrooks, C. D. et. Al. (2017) Selectively Distracted: Divided Attention and Memory for Important Information. Psychological Science; 28(8): 1103-1115.
Chang, Y. et. Al. (2017) The influence of media multitasking on the impulse to buy. Computers in Human Behavior; 70: 60-66.
Kee, K. & Kanai, R. (2014) Higher Media Multi-Tasking Activity Is Associated with Smaller Gray-Matter Density in the Anterior Cingulate Cortex. PLoS One; 9(9): 106698.
Rubinstein, J. S. et. al. (2001) Executive Control of Cognitive Processes in Task Switching. Journal of Experimental Psychology: Human Perception and Performance; 27: 763-797.
Mayr, U. & Kliegl, R. (2000) Task-set switching and long-term memory retrieval. Journal of Experimental Psychology: Learning, Memory, and Cognition; 26: 1124-1140.
Rogers, R. & Monsell, S. (1995) The costs of a predictable switch between simple cognitive tasks. Journal of Experimental Psychology; 124: 207-231.
