Why I ditch multitasking to optimize my performance: A neuroscientist perspective

computer with different-colored sticky notes

By Camila Almeida, Staff Scientist

I’m not very good at multitasking, but this fact doesn't bother me. As a neuroscientist, I know that the human brain can’t focus on 2 different things at the same time, so I don’t put a lot of effort into getting better at it. Multitasking increases my chance of error, negatively impacts my mental fitness, and can affect my performance in other Total Force Fitness (TFF) areas. Read on to learn how the attention system works, the impact of multitasking on brain function, and why mindfulness is a better approach to military performance and wellness. 

Just like a flashlight

narrow beam flashlight

Your attention system works like a flashlight. Some flashlight models have a ring in the front that allows you to make the beam of light more narrow and focused or wider and more dispersed. Regardless of how you choose to use the flashlight, you can’t direct the beam at 2 different objects at the same time. However, you can narrow your attention to complete a demanding task, such as solving math problems. Or you can make your attention system a little wider and enjoy a beautiful landscape when you drive (but not text) through quiet roads. 

wide beam flashlight

If I try to read while I listen to someone talk, I can claim I’m multitasking. In reality, I’m quickly shifting my flashlight beam from one task to another. These constant shifts happen within milliseconds, so I’m unaware of them and think I’m multitasking. But, if I keep doing that for a long time, I’ll miss considerable information from my reading and the conversation.

Scientists have tried to measure the human ability to multitask. The results confirm that the brain can’t do it. Participants from a research study had to either perform the tasks sequentially as assigned or they could try to work on the tasks simultaneously. For the first few minutes, multitaskers completed more tasks than non-multitaskers. However, as time elapsed, those participants who tried to work on multiple assignments simultaneously experienced decreased productivity and accuracy. The explanation is simple. The brain can only focus on one thing at a time, and when you try to challenge this fact, your performance suffers. 

Multitasking and Total Force Fitness

The experiment described above is an example of the impact of multitasking on mental fitness–reduced productivity and accuracy. In addition, after a day of trying to multitask, you feel mentally fatigued and can no longer focus. If you quickly shift your focus between tasks, your brain has to spend more energy to complete all tasks than when you focus on one task at a time. For every task switch, the brain needs to stop what it was doing, engage with another task, calibrate the resources for that particular task, start slow, and get up to speed. But if you multitask, by the time your brain gets up to speed, you switch tasks again and you use all your brain resources before the end of the day. 

Think about your car’s fuel efficiency in the city versus on the highway: Constant stops in the city make you drive fewer miles per gallon. At the end of a busy day, it might feel like you’re pressing hard on the gas pedal to finish your tasks, but that doesn’t help because you ran out of gas. This can become a source of stress which can further degrade performance.     

Multitasking can also have a negative effect on other aspects of TFF, such as social fitness. For example, if I spend “quality time” with my family and friends but I check and use my cell phone the whole time, I might communicate that I’m ignoring them or I don’t value our relationships. Modern life is busy. I often feel that I don't have many opportunities to engage socially with the people I care about. For this reason, I choose to silence my phone and give my full attention when I spend time with my family and friends.

My nutritional performance can also suffer when I decide to multitask. In the past—in an effort to be productive and make the best use of my time—I would eat in front of the computer while I worked, and that resulted in mindless eating. I didn’t pay attention to my food’s taste and texture (much less to my hunger signs), which often resulted in overeating. I broke that habit when I realized that a 20-minute break is all I need to enjoy my lunch and practice mindful eating. 

An alternative to multitasking: Mindful attention 

A better approach toward military wellness and performance is to live in the moment and tackle one task at a time. If you are used to multitasking, it might feel hard at first. Every time something in the environment (for example, a new email pops up in your inbox) or an internal thought catches your attention, you might feel the temptation to switch tasks or work on 2 things at the same time. Don’t get discouraged! Over time, you will learn to minimize distractions as you focus for long periods on a single task. As you experience the benefits of mindful monotasking, you can apply this practice to all aspects of TFF to support your performance.

Sometimes your job might require multitasking, and that’s part of being a Service Member. But if you keep multitasking even when you don’t have to, you’re likely to be exhausted by the end of the day. When you have the option, mindfully selecting to be present in the moment can help you rebound and perform better.


Disclosure: The opinions and assertions expressed herein are those of the authors and do not reflect the official policy or position of USU or DoD. The contents of this publication are the sole responsibility of the author and do not necessarily reflect the views, opinions, or policies of The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. Mention of trade names, commercial products, or organizations does not imply endorsement by the U.S. Government. The author has no financial interests or relationships to disclose.