We all need to concentrate from time to time, not least at work.
However, we find that staying focused or concentrated for prolonged periods of time is demanding and tiring. Our brains are not made for concentrating continuously. On the other hand, allowing our attention to float freely and change spontaneously among various internal or external objects, as in nondirective meditation or when you spend time in nature, seems to activate parts of the brain that help us process stress and emotions. The effect is more energy and a greater degree of well-being. This seems to be one of the effects of a free mental attitude, in addition to increasing selfawareness and creativity.
Survival of the fittest, Darwin said. Maybe the fittest are people with free-floating attention, rather than narrow concentration. Let’s see.
Have you ever felt really exhausted and depleted of all energy after a day’s work at the office? When you think about it, isn’t that a bit strange? After all, all you have been doing all day is sitting! You may have gone to the canteen for a brief lunch, or maybe down the hall for a meeting or two, but otherwise you have been resting your body the whole time. So there is something about concentrated, mental work that tires and exhausts us.
You might try to explain to other people that you’ve been concentrating hard all day, strongly focused on the demanding letters and numbers on your computer screen, avoiding all distractions to get your presentation or report or whatever it is finished on time.
The fact is that concentrating continuously on reading or writing for a length of time can be very demanding, leaving you with a great need to restore energy. But we don’t seem to have a good explanation for that. You might instinctively take many micro-breaks during your work day, by glancing out of the window for a couple of minutes, making a brief visit to the restroom, tying your shoelaces, etc., reducing the continuous demand on your mind. On days with high pressure to really finish the whole workload before you finally go home, though, you avoid even these micro-breaks.
Let’s think about it for a while. In many modern lifestyles, including working in an office or workshop, or studying for an exam, we are dependent on our ability to stay focused and concentrate for long periods of time. From a strict genetic perspective, our species should have developed brains that would enable us to concentrate without stopping for days on end, without the need for breaks. That would have made sense. And it would have given us an advantage in competition with other races or species without such a capacity.
A few American psychologists have looked into this problem (Kaplan, 1995b; 2001). They are not geneticists, so they can’t really prove their argument, but it does seem to make sense. They have suggested a certain similarity between the spontaneously flowing attention used when walking in nature and while meditating. It has been proposed that some “restorative” objects or environments, e.g., many natural settings, do not require directed attention, and thus provide an opportunity for spontaneous reflection and to initiate recovery from directed attention fatigue and stress (Kaplan, 1993; 1995; Kaplan and Kaplan, 1995).
During most of the time human beings have walked the earth, we have been doing just that: walking around. Our survival on the East African savannas, where most researchers now believe humankind first came to be, was dependent not on our ability to concentrate, which we only occasionally or maybe relatively seldom had to do, but on our ability to have a free-floating focus of attention. We would let a multitude of visual experiences, sounds, and smells stream through our minds, without paying much more attention to any of these stimuli than to the others. Our attention would float freely between the wind in the trees, birds flying in the distance, the flickering hot air above the ground at a distance, and a herd of antelope down by a lake. But at times, the smell of a dangerous predator, the sight of some edible leaves, or the trickling sound of water would spontaneously catch our attention. We wanted to focus on these things. Letting our brain’s attention networks briefly analyze all stimuli takes a few seconds, before we again resume our continuous and spontaneous scanning of the external, and sometimes internal, environment.
Our survival, the argument goes, has been crucially dependent on a continuous use of an effortless mode of attention, much more so than a continuous concentrated mode of attention. We are not designed to stay narrowly focused for long periods of time. In fact, doing so would for most of our history be dangerous, as it would make it difficult for our free-floating attention to pick up novel threatening or advantageous things in the distance. Besides, mind wandering has additional functions. Emotional processing (see later) is one. Understanding ourselves in a continually changing social environment is another.
Activity in the outer layer of the brain, the convoluted cortex, is responsible for all conscious mental activity, such as sensory perception, voluntary motor control, attention, language, thoughts, and emotions. Different types of thoughts and attention are processed by three large networks of brain areas: Default mode network —spontaneous, self-related thoughts of past and future episodes. Such thoughts are often called mind wandering. This network is active when we do not have any external tasks to tend to. Dorsal attention network —deliberate, active attention to present tasks, keeping necessary things in memory for the seconds needed to attend to the task. Salience network —spontaneous redirection of attention to something that emerges here and now.
But there is another twist to this line of argument, and here there is much more scientific evidence. Mental fatigue after hours of concentrative work is characterized by an inability to continually keep our minds in narrow focus. To escape from this condition of mental fatigue we need to actively restore our capacity for concentrated attention. And what is the trick to restore this capacity? It is, says Kaplan, to spend time with an effortless mode of attention! Certain environments or activities are more effective in inducing this mode of attention, especially walking in nature. And, they say, meditating.
Mental fatigue and depletion of mental energy is closely linked to psychological stress. On the one hand, it is in itself stressful to maintain narrow concentration for hours at a time. On the other hand, stressful emotions, most typically anxiety or aggression or a mixture of both, may easily distort concentrative focus (Lazarus, 1993). So could it be that the opposite of concentration, i.e., effortless, open attention, may reduce the impact of stressful emotions? Let’s take a look.
First of all, effortless attention, which is similar to what we in this book call a free mental attitude, facilitates spontaneous thoughts and mind wandering. These mental activities spring out from the brain’s default mode network. So, we may rephrase at least one aspect of this question as follows: Is there any evidence that the default mode network is involved with the processing or regulation of emotion? From what we have seen so far, mind wandering is cognitive in nature, right? It’s recollecting and thinking about memories. This is the stuff of thinking, not of feeling, isn’t it? The distinction between these two may not be as clear-cut as we normally think. But let’s look at the science:
A growing number of psychologists believe there is a link between the two—default mode network activity and emotional processing (Smallwood and Schooler, 2015; Smallwood et al., 2009). First of all, by around 2010, reports were emerging that major depression disorder was linked to defects in default mode network functioning. In 2011, a group of Canadian, German, and Chinese researchers, led by Georg Northoff at the University of Ottawa, published a study where they basically said: One thing is problems with default mode network functioning in emotionally disturbed people, but what can we see in psychologically healthy people? Does a normally functioning default mode network play a role in emotional processing? (Northoff et al., 2011)
Though spontaneous thoughts and mind wandering are very similar terms, strictly speaking, mind wandering is the mental phenomenon where the mind spontaneously is completely absorbed in other thoughts than the immediate task at hand, while the term spontaneous thoughts encompasses both mind wandering and other spontaneous thoughts that may run parallel with attention to the task at hand. Most scientific articles do not make this distinction, commonly using mind wandering for both cases. For ease of writing, we will only use the term mind wandering for the remainder of this chapter.
In order to provide an answer to this question, they recruited 30 subjects and scanned their brains with functional magnetic resonance imaging, or fMRI. This technique allows the researchers not only to visualize brain structure, as in regular MR scans, but also to detect the activity level of various brain regions while the subject performs cognitive tasks, or just rests between tasks.
The researchers had the subjects listen to voice recordings of an experienced actress reading a series of 15 semantically neutral sentences of equal length, such as “The chairs are made of wood.” Each sentence was read with five different emotional intonations: happy, angry, sad, fearful and neutral. The subjects of the study were asked to rate the emotion of each reading. They were also tested for their ability to identify different bodily states or sensations.
The results were remarkable. The higher activity in three core default mode network regions (ventromedial prefrontal cortex, dorsomedial prefrontal cortex, and posterior cingulate cortex) during rest, the higher the subjects scored on identification of emotions. There was no such link between default mode network activation and scores on identifying their own bodily sensations. In other words, people with high baseline levels of default mode network activity, and presumably then also high levels of mind wandering, seem more adept at identifying emotions in others, at least from hearing their voices.
The implications of this study are twofold: First, a whole new set of brain areas seems to be involved in the processing of emotions. We have known about the amygdala and the insula, and their interplay with hippocampus and the prefrontal cortex. But connecting other areas of the cortex to emotions is interesting. Second, these new areas of emotional processing would not be expected to play a role in inhibiting stressful emotions. Rather, the role of the default mode network in emotional processing could be expected to assist us in understanding the emotional aspects of ourselves and others—something like empathy. This is really what the Northoff study seems to show.
What about emotions during mind wandering? Do we experience emotions when our minds wander? An elegant, but perhaps somewhat biased, study in the journal Science in 2010 by Killingsworth and Gilbert from Harvard used a smartphone sampling technique (Killingsworth and Gilbert, 2010). Participants in the study were required to download an app designed by the researchers. The app would cause a signal to sound from the phone at random times during the day, upon which the owner of the phone should reply to a few brief questions about what they were doing, thinking about, and how they were feeling. One observation from this study was that people were moderately less happy when their mind wandered than when it did not. As a result, the authors used the following title for their article: “The wandering mind is an unhappy mind.” For this, they have been criticized, probably rightfully so. They did also show, in fact, that our mind tends to wander more toward pleasant topics (42.5%) than towards unpleasant (26.5%) or neutral topics (31%). Other researchers (Poerio et al., 2013) have later shown that when we experience sad feelings during mind wandering, the feeling is there before mind wandering starts; in other words, the mind wandering does not initiate the emotion, but maybe the other way around. In any case, however, the Killingsworth study did, undisputedly, show that we are involved with emotions almost 70 % of the time we spend mind wandering. Mind wandering is thus intricately linked to feelings. Not only our thoughts wander, but our feelings too. We may experience shifting phases of happiness, or sadness, or worry, or curiosity, or irritability when our minds wander. It’s possible that this is a good, necessary, and healthy function. Rather than being something to avoid, this emotional processing helps us to understand ourselves and others, helps us to deal with stress and worries in a constructive manner, and to resolve difficult questions from our daily lives.
Given the fact that mind wandering is not only a purely cognitive activity, but that it also may be part of emotional processing, it is not surprising that changes in default mode network activity or connectivity seem to be linked to various affective disorders. Among these are post-traumatic stress disorder, social anxiety disorder, and obsessive-compulsive disorder. In one study from 2014 (Shang et al., 2014), researchers found that there was reduced connectivity, or interplay, between areas within the default mode network in earthquake survivors who had developed post-traumatic stress disorder compared to survivors who did not. Likewise, childhood poverty and stress may lead to aberrant default mode network connectivity, and depression in adolescents and adults is associated with imbalance in the default mode network and the mind wandering we experience during resting states (Gaffrey et al., 2012; Sripada et al., 2014; Ho et al., 2014; Northoff et al., 2011). So, both reduced total default mode network activity and a change of balance in activity between the different sub-regions of the network seem to be associated with disorders of emotion. In other words, if the default mode network is not in spick-and-span order, like a well-groomed engine, something goes wrong with our feelings.
This field of research is still in its infancy, but it already seems clear that the default mode network, along with its mental correlate mind wandering, is involved with emotion and emotional processing.
Let us summarize what we have seen so far. Concentration seems to be a limited resource, i.e., we can’t concentrate for long without becoming exhausted. In the long run, while engaging in demanding tasks, we lose much of our ability to concentrate and need to refuel something we can call mental energy. Concentrating continuously for a long time is often stressful in itself, but also the other way around: stress often makes you concentrate, thus causing you to lose more energy. Also, we have seen that though the default mode network is known to be responsible for mind wandering, it also is involved with the processing of emotions and stress. Mind wandering with a free mental attitude gives a discharge of emotionally-loaded cognitive residues. In other words, a free mental attitude seems to be one of the tools we need in order to refuel mental energy after periods of prolonged concentration and stress.
Since 2010, a growing number of scientific studies have documented that the practice of meditation may have a modifying effect on both the structure and function of the default mode network. Though we so far don’t know a lot about the mechanisms of these effects, this research still points to an intriguing concept: meditation may induce beneficial anatomical and physiological changes in areas of the brain involved with the processing of self-image, emotions, and stress. Let’s look briefly at some of the evidence supporting this notion.
It started out with an EEG study by Travis and coworkers, who for many years have studied the effects of Transcendental Meditation, a technique of nondirective meditation (Travis et al., 2010). In 2010, they found that midline brain cortical activity in the alpha frequency band was increased during meditation compared to resting. There were strong indications that this activity originated in the default mode network. Strong alpha waves are often attributed to resting. These observations seem to confirm what has been shown many times in other studies of the relaxation response, that we experience deep rest during meditation. But it points to a new twist, that possibly increased default mode network activity is intricately linked to this resting.
The year after, a Korean study of brain wave vibration meditation (Jang et al., 2011) suggested that long-term practice of meditation may also be associated with increased integration between default mode network regions at other times than during the practice of meditation. Brain-wave vibration meditation is a kind of moving meditation that is designed to help quiet the thinking mind and to release negative emotions through performing natural rhythmic movements and focusing on bodily sensations. So meditation may possibly have effects, related to spontaneous processing of thoughts and emotions, outside of the time spent meditating as well. Our mental processing traits seem to be changed by meditation.
Later on, articles in more high-impact science journals have again showed that meditation seems to initiate changes in the connections and signaling between various default mode network regions. In 2011, a brain fMRI study from Judson Brewer at Yale and collaborators at Columbia University and the University of Oregon again demonstrated meditation-based changes in the default mode network (Brewer et al., 2011). Interestingly, they studied the effects of three common meditation practices: focused attention, open monitoring, and loving-kindness meditation. The two former are extensively used in mindfulness meditation. On the one hand, they concluded that some of the regions of the default mode network showed reduced activation in experienced meditators for all three meditation types. However, on the other hand, they found increased contact and integration between two of the other default mode regions, as well as with the dorsolateral prefrontal cortex, which is not part of the default mode network. These last three areas together have been implicated in self-monitoring and cognitive control. The changes were present both during and outside of meditation practice. Though the implications of these studies must be investigated further, they all point to the fact that meditation is a mental activity that may change the structure and function of the brain, in this case the default mode network. One would expect concomitant changes in mind wandering, i.e., in the spontaneous processing of thoughts and emotions.
Similar, but slightly different results were found with experienced mindfulness meditation practitioners in a study in 2013, by a team of French and Canadian researchers (Taylor et al., 2013). Basically, they found that experienced mindfulness meditators, compared to beginners, had weaker connections between some default mode network regions that are involved in self-image processing and recognition of one’s own emotions. Possibly, this may show that different meditation techniques have slightly different functional profiles, or effects on the default mode network. One may speculate that these subjects are less adept at processing self-image or emotions, so that they react less to fluctuations in emotions, leading to more stability, but less inward sensitivity. This would have to be tested in other studies. On the other hand, they also showed stronger connections between other default mode network regions (e.g., dorso-medial prefrontal cortex and right inferior parietal lobule). The authors speculate that the observed changes may reflect increased emotional stability, reduced strain on self-image during emotions, and increased capacity for being in the present moment. In some situations, this may be a desired trait, but in other situations it may not be as beneficial, for instance in reacting to and understanding the emotions of others at your workplace and in your family.
Later on, a number of EEG and brain imaging studies have confirmed that meditation does in fact induce changes in default mode network activity and connectivity, along the same lines as in the studies described above. One study, however, showed that youths who practice meditation seem to change more often between different brain states, e.g., between salience/emotion, default mode and central executive networks (Marusak et al., 2018). This may possibly indicate that meditation training may facilitate greater mental flexibility.
We have now seen that the ability to concentrate is a limited resource, susceptible to fatigue, more so in stressful conditions. We have seen that the default mode network, responsible for mind wandering and self-referential thought, is involved in aspects of emotional processing as well, and that meditation can in fact modify activation patterns and connectivity within the default mode network. The question remains, though, how can the practice of meditation lead to beneficial ways of dealing with emotions and stress? This is an important question, but one where science is still far from reaching final conclusions. We can still use some of the available research to discuss possible answers.
A team of psychologists at the University of British Columbia in Canada—Matthew Dixon, Kieran Fox, and Kalina Christoff—have extensively discussed the link between “externally and internally directed cognition”, and “intentional and spontaneous mental processing” (Dixon, Fox & Christoff, 2014). Externally directed cognition is a term experimental psychologists use to describe thinking about things or events in the world around us, such as when you’re cooking your food or playing a computer game. Internally directed cognition, on the other hand, is when you focus on your own thoughts, memories, or internal images. Many studies have pointed out that these two types of thought often compete in your mind; if you focus on discussing your company’s strategic future at a work meeting, it’s difficult to indulge yourself in remembering images from your recent vacation at the same time—or vice versa.
Thus, these psychologists argue, the two types of thought, internal and external, are not necessarily in opposition to each other. When we engage in either of them with high levels of intensity, like when we concentrate on something, they are increasingly likely to compete in our minds, i.e., it’s difficult to think about both at the same time. However, if one or both of them involve spontaneous thinking without concentration, we can engage in external and internal thoughts at the same time. They will not compete, the psychologists say. This is probably what underlies moments of spontaneous mind wandering even when we engage in external tasks. It is well established that such mind wandering increases when the external tasks are well rehearsed and we can perform them with little effort, such as driving a car, if you are an experienced driver!
Interestingly, they also argue that the brain regions we use when thinking about outer and inner things (i.e., during externally and internally directed thought processes) overlap to some extent. Both involve several brain regions. Many of these are distinct, but the lateral prefrontal cortex seems to be common to both. That’s why the two types of thought often compete in our minds. You can only use this area of the brain for one thought at a time. However, the researchers say, at lower levels of intensity, i.e., with higher levels of spontaneity and less concentration, outer and inner thoughts rely on different neural structures. During these moments, they don’t compete for use of the lateral prefrontal cortex, thus enabling them to co-occur without interference. The implications are that it could be possible to cognitively attend to external tasks in manners that are less demanding, giving less fatigue.
Emotions appear in consciousness through activity in parts of the brain, e.g., the amygdala, insula, and parts of the cortex. Thousands of nerve cells, both in these and other brain areas, will then process this emotional information by analyzing and understanding the feeling, making cognitive sense of it, monitoring the effect the emotions have on other parts of the brain and the body, understanding the source and the future implications of the emotions, and enhancing or diminishing the emotion according to the typical reaction patterns of the person as well as any external needs. During this process of both sensing and making sense of the emotions, they are usually changed in some way and either stored, intensified, or allowed to pass away. Authors, artists, and musicians actively use and play with this function of the brain in order to make us react to their stories, images, and music. If emotions are found not to represent something that seriously threatens us, psychological and muscular tension may abate. With a degree of personal maturity, emotions may be integrated in our selves, becoming part of the way we perceive and react to the environment around us. The processing of emotions may thus serve to consolidate synapses, pathways and networks in the brain.
Several other psychologists have discussed the functional implications of being attentive to something with different levels of intensity or spontaneity. Thus, it has been suggested that defocused attention, allowing the presence of other thoughts and mental activities in addition to what is present in your mind when you are employed in direct tasks, on the one hand may be a source of distraction, but on the other hand may also be an adaptive mode of mental processing, for instance during depressed moods. Defocused attention is similar to what in Acem Meditation is called a free mental attitude, when the repetition of the meditation sound is in the center of your attention while spontaneous thoughts wander through the fringe of your attention. Thus, defocused attention, some researchers say, may assist us in identifying alternative strategies for achieving relevant goals, and also increase our memory for items in the periphery of attention (von Hecker, 2013; von Hecker & Meiser, 2005; Christoff, 2011; Limb & Braun, 2008). Similarly, free association, or random episodic memory, has long been the working tool in psychoanalysis in the treatment of several psychiatric disorders (Andreasen et al., 1995). Furthermore, Kaplan and others have used the term cognitive disengagement to describe adaptive measures by the individual to mentally redirect attention from plans or strategies that don’t lead in the right direction (Livneh et al., 1996). A more popular description of the same phenomenon would be letting go of something in your mind. You don’t intentionally hold on to a thought or a concept or an idea, but allow other things to take their place in your mind.
Similarly, authors from different fields and times have noted the distinction between a narrow, directed attention and a more open, inclusive attention. This has led to expressions such as attentional focus and fringe (Eriksen, 1972), voluntary and involuntary attention (James, 1892), directed attention and fascination (Mesulam, 1985; Kaplan, 1995), effortful and effortless attention (Davanger et al., 2010; Xu et al., 2014; Tang & Posner, 2009), and concentrative and nondirective attention (Xu et al., 2014; Davanger et al., 2010). Though there may be some differences between these pairs of concepts, the first in each pair describes attention that is concentrated and limited in scope, susceptible to fatigue, and where effort is required to maintain focus over time. The second is open to spontaneous mental activity, is active also at rest, and is not exhaustible.
The latter of these two attentional types is similar to the mode of attention that is used in several types of meditation, especially in nondirective meditation. Thus, practitioners of Acem Meditation in deepening retreats may use a free mental attitude, with an attention that includes ongoing mind wandering, continuously for hours or even days, without tiring. Meditation under these conditions may be akin to the spontaneously flowing mind associated with walking in nature, as we noted in the beginning of this chapter. Thus, allowing your mind to wander freely during nondirective meditation, like wandering in nature, may open up for creativity and inner resources in ways that do not make you tired. This is the power of the wandering mind.
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