How to pat your head and rub your belly at the same time effectively?
Controversial brain. Part 1: Multitasking — doing it the right way!
Is multitasking good or bad for you? Why do you start forgetting tasks when multitasking a lot? Is there a right way to do it?
I am sure you’ve heard plenty of different opinions about multitasking. Some people you know claim to be “professional multi-taskers.” They are proud of doing multiple things at the same time and subsequently being more effective at their jobs (it might even be you!). You may also recall your friends or colleagues complaining about feeling overwhelmed and exhausted after a full day of multitasking. And, when you multitask, you may have noticed that some things start simply “slipping your mind”.
Many employers think about multitasking as a desirable skill for their hard-working employees to have. Job applicants consider adding the ability to multitask to their resume to gain a competitive edge. Although multitasking has become an essential part of our life, it remains quite too often misunderstood. The controversy arises when we want to achieve as much as possible within a limited time; yet we hear the words of caution about the potential adverse effects that multitasking may have on our brain, especially on our memory. So, should you avoid multitasking entirely? How does multitasking affect your attention and memory? How to use multitasking for your benefit? There are no straightforward answer to these questions. Let’s take a look together at the accumulated scientific knowledge on this topic to make the best decision for ourselves. But first, let’s find out if multitasking even exists!
Multitasking: doing things in parallel or switching?
Let’s start with a definition. Here, multitasking means attempting to do multiple tasks at the same time. For example, try using your hands to pat your head and rub your belly simultaneously. Consider also talking on the phone when scrolling over your Instagram feed. Now, what about listening to a podcast while attempting to make that new vegan recipe from the cookbook your friend just gave you? Or giving a talk on Zoom while checking the questions in the chatbox? Taking notes during your college algebra class the other day can also be considered a type of multitasking — what a surprise! As easy as it might sound, some of these are not the most straightforward tasks to perform!
Our most common misconception is that when we multitask, we are doing two things simultaneously — in parallel (referred to as dual-tasking multitasking). This appears to be true only when you include in multitasking some automatic tasks which you have practiced and have been repeatedly doing over an extended period, like walking, eating, and brushing your teeth. Think about reading while eating, exercising while listening to music, taking a shower and singing (when was the last time your neighbor complained?) However, many tasks are more complex and require our active attention. We will refer to them as non-automatic tasks. Unlike previously discussed multitasking examples, these tasks are not performed simultaneously. For example, writing an email while talking to your friend is not happening in parallel. The fact is, you are switching from one task to another (referred to as task-switching multitasking). According to the neuro-cognitive model of multitasking, dual-tasking multitasking and switching-tasking multitasking happen in different areas of the brain [1]. It means that there are fundamental differences between the different types of multitasking, supported by distinct processes within the brain.
To sum up, it turns out that multitasking in fact exists and we multitask more than we think we do (remember watching that Netflix movie and eating popcorn last night)! This implies that multitasking is virtually unavoidable and there is much more to it than we might have expected! Multitasking does not always mean doing things concurrently. Cognitive psychologists distinguish two multitasking domains: dual-tasking and switching-tasking. The first occurs when two tasks are performed at the same time (parallel processing), and the second occurs when tasks are performed in sequence — one after another (sequential processing). However, we may still think that we perform them simultaneously. Whereas dual-tasking happens mostly when we complete automated tasks well familiar to us, switching-tasking requires us to actively pay attention to the things we are doing while switching from one task to another.
Multitasking: how to avoid an overload?
Cognitive neuroscience tells us about a “processing” system in our memory supported by the prefrontal cortex of our brain (Fig. 1). It is referred to as working memory. We can compare it to the RAM in our computers. Like RAM, our working memory has a certain limited capacity. Within that limited capacity, working memory handles all the information we receive, manipulates it, and distributes it where necessary (for example, to the long-term memory storage). You can test the capacity of your working memory by performing a Digit Span Task [2]. This is a simple task where a sequence of digits is being presented — one digit at a time for you to remember and report it afterward. If you have not trained yourself with memory optimization techniques yet, you should be able to recall about 7 digits of the sequence in the same order. This will represent the capacity of your working memory — the amount of information your working memory can handle at a given time, such as writing your new friend’s phone down while he tells the numbers to you. Even making sense of a sentence that your teacher just mentioned requires you to maintain all the words of the sentence in the temporary storage — your working memory.
According to one of the most prevailing working memory models proposed by Alan Baddeley [3], working memory consists of three building blocks (Fig. 2): phonological loop, visuospatial sketchpad, and the central executive. The phonological loop deals with the tasks related to processing verbal and auditory information. Think about reading or listening to a song. The visuospatial sketchpad handles the tasks associated with visual and spatial information. Your working memory is actively using this component when you are navigating your way to the library, where you prepare for your finals. Importantly, both a phonological loop and a visuospatial sketchpad are supported by different systems within the brain.
What do the building blocks of your working memory system have to do with multitasking? Believe it or not, but when you are trying to perform two tasks that require the involvement of the same component of your working memory (either phonological loop or visuospatial sketchpad), you most certainly may run into overload issues with your working memory (After all, it has limited capacity — remember 7 digits!). Now, it’s time to recall your attempt to pat your head and rub your belly at the same time. In this case, you are using the same component of your working memory — the visuospatial sketchpad. That is why this task may not feel easy at once. However, you might improve your performance by practicing and making both of the tasks automated, which will require less involvement from your working memory and result in better performance. Many athletes are faced with the challenges of combining the tasks from the same working memory domain at the beginning of their training. They may even experience a temporary decline in their cognitive and motor performance. However, in a long run, with sufficient training, their motor performance improves and working memory skills along with attention get boosted [4]. Combined together, these long-term effects may allow athletes to reach new levels of their potential.
Giving your talk on Zoom and checking the chatbox for questions at the same time would also constitute a challenge — this time because of the simultaneous use of the phonological loop component of your working memory. Now that you got familiar with your working memory structure, do you think listening to a song with lyrics in it while preparing your schoolwork is a good idea? Let’s use knowledge about the working memory components to help you be effective at multitasking! For example, when multitasking, choose the tasks from different working memory categories instead of the same category. This means that the best approach is to combine tasks that have both phonological loop and visuospatial sketch pad components. For example, listen to a podcast when jogging (not when you are reading the recipe book) or chat with your friend when sipping a cup of coffee (not when you are listening to your GPS voice in the car). When using these simple combination rules, you will see fewer problems in your task performance and fewer problems with forgetting simple things, such as what your professor just said. However, if you are faced with tasks from the same working memory domains — you can train yourself in multitasking. Do not worry about your suddenly decreased performance. This effect will not stay forever. With proper training, your performance in both motor and cognitive domains will improve. It will just take time.
Multitasking and productivity: does your perception matter?
Early multitasking studies (e.g., [5]) have demonstrated performance errors made during multitasking, resulting in reduced overall efficiency and productivity. These findings were supported by multiple other studies conducted since then. Recently, a group of researchers from several universities conducted a meta-analysis study [6]. It means that they combined and analyzed the data from multiple studies on multitasking. This included 8,242 participants across 32 different studies.
To start with, the authors demonstrated that engaging in multiple tasks may result in diminished performance, which confirmed what was known already. However, what the authors discovered next was pretty surprising! Quote: “individuals who perceived an activity as multitasking were more engaged and consequently outperformed those who perceived the same activity as single-tasking.” What became apparent is that a critical factor in performance was people’s own perception of what they were doing. In fact, simply thinking about their activity as more or less advantageous separated people based on their performance!
To illustrate that, let’s say people were completing the same task. Some of them were interpreting it as multitasking, and some were thinking of it as single-tasking. Most striking is that the people believing that they were multitasking performed better on tasks than those who believed they were single-tasking. Isn’t that amazing?! So, after all, it is not multitasking or single-tasking per se that affects the performance, but rather our interpretation and thoughts about how we do things. Simply perceiving the activity as multitasking increased motivation and improved performance. People who perceived themselves as multitasking were more engaged and attentive to the task.
What does this information mean to you? That your perception is the key. If you perceive multitasking as beneficial (almost all of us believe this about multitasking), it will reflect on your performance. So, irrespectively of what you do, the best strategy is to go “all in”, truly believing that this is the best way to do it. With the right perception about what you do — you can achieve higher performance than those with a different perception.
Now that we know multitasking can have favorable outcomes on our tasks, how does it affect our brain and health?
Multitasking: how does it affect our brain?
The same multitasking study mentioned earlier [5] has demonstrated increased mental overload during multitasking. As you already know from our previous conversation, non-automatic tasks that you perform during multitasking are not executed by your brain simultaneously. Instead, your brain needs to switch from one task to another. This switching has a price that you need to pay: Your attention gets scattered, making it harder to focus on one goal. The switching from one task to another is triggered by the prefrontal cortex (Fig. 1). Extensive switching depletes the limited resources of the prefrontal cortex, resulting in its reduced activation. Why is this worrisome? It is because our prefrontal cortex is responsible for executive functions. Therefore, the changes in the prefrontal cortex affect important things such as decision making, planning, attentional control, working memory, and cognitive flexibility. This means that the more multitasking you do, the more difficult it becomes to make decisions. For example, suturing in conjunction with decision-making may result in significant deactivation of the prefrontal cortex and, consequently, negatively affect the surgeon’s performance during laparoscopic surgery [7].
The depleted resources of the prefrontal cortex due to multitasking impede the processing of incoming information, thus, resulting in people making more impulsive decisions (Fig. 1). In a consumer decision-making study, the authors [8] gave the participants a choice of chocolate cake and fruit salad. Right before that, the participants were provided with a sequence of either 2 or 7 numbers to manipulate the processing of mental resources (a sequence of 2 digits allows for high processing resources allocation, whereas a sequence of 7 digits limits the processing resources). Interestingly, those who were later asked to recall a sequence of 2 numbers tended toward the fruit salad. At the same time, the participants, who were asked to recall a sequence of 7 numbers, were more likely to select the cake. Do you remember the average working memory capacity of 7 consecutive digits we talked about? So, it looks like the closer we are approaching the working memory capacity, the more difficult it becomes to allocate our neural resources to decision-making executed by the prefrontal cortex. This results in a more emotional type of response taking over, supported by the limbic system.
So, should you stop multitasking to preserve your attention, memory, and ability to make decisions? That would be ideal, but is it possible, with the current increase in information load and job demands? Probably not. However, you can approach multitasking wisely. How do you do that? One option is choosing a strategy based on the cognitive demand of the task at hand. This means that if the task requires particular attention, such as writing a book or completing a surgery, focus on it entirely.
If you are fairly familiar with the task but still need to be attentive — you can combine it with an automated task. Such a combination might even be beneficial. For example, pedaling a stationary bicycle while reading, having your daily morning walk while reciting affirmations or rehearsing new phrases of a language that you decided to learn, or reviewing a new course lesson while brushing your teeth. Some anecdotal evidence suggests that pairing tasks, requiring some type of low to average level physical activity benefit the concurrent task demanding cognitive involvement. Why is it so? Because the performed physical activity helps increase the blood flow and oxygenate the brain, which in turn supports the processes necessary for the cognitive task execution. One of the prominent “memory athletes” I talked to told me a story about creating his first memorization system during the daily treadmill workouts he was forced to start because of his heart-related health issues. There is no doubt that the combination of the workout and memory optimization exercises was particularly beneficial in this situation.
Importantly, avoid combining tasks that both require a high level of active attention. This would include listening to a lecture and answering an email, or working on your goal setting and checking your social media accounts. Probably, you would not want your surgeon to check their Facebook account while they’re operating on your knee!
Be careful with multitasking, though, if you had any recent neurological conditions, such as traumatic brain injury, concussion, or stroke. Often, after these neurological events, the resources of the brain are more limited than in healthy conditions. Dividing the neural resources between tasks, one of which is motor, when using the limited resources of the brain can result in balance problems and even falls. Similar is true for those with attention deficit disorder (ADD) and attention deficit hyperactivity disorder (ADHD). People with these conditions already tend to have limited attentional resources. Multitasking adds a toll on these already limited attentional resources leading to even lower than initial attention span and higher distractibility. The ability to process information in order to multitask becomes even more limited. Depleted brain resources result in a higher number of mistakes, lower performance, impaired ability to recall learned information, and one feeling exhausted, stressed, and overwhelmed.
Let’s bring it home!
To summarize, multitasking is not what most of us think it is. Most of the time, we are not doing several things simultaneously but instead switching from one task to another. This results in depletion of cognitive resources: changes in attention, memory, and executive function. However, we still can use multitasking for our benefit if we approach it the right way! Here are some tips to keep in mind:
- When possible — focus on completing one task at a time. This is especially important when you are working on high-attention demanding tasks. This is also true if you experienced any recent neurological events or have ADD/ADHD.
- If needed — you can multitask, but remember: Do not multitask when the task requires your increased attention (e.g., new or complex task, like manuscript writing or taking a test);
- Combine automated tasks — the ones that require minimal attention from you (e.g., daily walk, stationary bicycle pedaling, brushing teeth, taking a shower) with more attention-demanding tasks (reading, rehearsing a speech, reviewing lecture notes).
- You can train yourself to perform simultaneous tasks (remember the athletes!) In spite of the initial decline, your motor and cognitive performance will get better in the long run. Even patting your head while rubbing your belly becomes possible if you continuously rehearse and automate these tasks!
- Make sure to combine tasks processed by different working memory domains — the phonological loop and the visuospatial sketchpad. Singing when taking a shower is cool, but do not try winning a sprint while constantly evaluating and comparing your own position and the position of your competitors.
- Regardless of what you do — make a conscious decision to do your best based on the knowledge you have. Evaluate your performance and make corrections if needed. Go all-in with the belief that your used strategy is the most successful. Your perception matters!
Written by Milena Korostenskaja, PhD, edited by David Smehlik, Lauren Levy, Muhammad Ali, David Martin, Ivan Korostenskij, and Ausra Daugirdiene, with artwork also by David Smehlik.
Milena Korostenskaja, PhD is a neuroscientist, focusing on clinical applications of Brain-Computer Interfaces (BCIs). Milena teaches neuroscience-related courses to both graduate and undergraduate students. Milena founded The Institute of Neuroapproaches, where she helps STEM professionals succeed in their careers by utilizing neuroscience-based coaching approaches.
David Smehlik works in tech as a Product Designer who later studied molecular biology to identify a rare medical condition that affects one side of his family. He’s interested in brain preservation.
Lauren is a researcher focused on neurodegeneration in retinal neurons. During her undergraduate studies, she co-lead NeurotechUofT’s Neuroscience & EEG team in the development of BCI-controlled bike signals, drones, and a mechanism for detecting microsleep in vehicle drivers. She now serves NeurotechUofT as an alumni advisor.
David Martin worked in the field of engineering and technology; performs a writing editor role at The Institute of Neuroapproaches.
Ausra Daugirdiene, PhD, specializes in psychophysics and human sensory perception.
Ivan Korostenskij studied behavioral neuroscience; focuses on research aiming to extend human life and improve memory.
References
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