Why minds wander

One goal of meditation is to identify emotions and thoughts that arise, and to remain equanimous with them—that is, to not judge them, or push them away, or cling to them. Over time, meditation may help dampen the attention-grabbing power of these thoughts both during practice and in daily life, which may consequently help deepen meditation practice.

This is encouraging for meditators. However, when meditators fail to remain equanimous, the effects of thoughts that arise during practice could be detrimental. This is a straightforwardly empirical proposal, and should be assessed in terms of the explanations it affords, and by whether the predictions it makes are confirmed or disconfirmed. Before I discuss explanation and prediction, however, I wish to note two things.

First, it would certainly be useful if the cognitive control system contained such an operation. Humans are sophisticated agents, with multiple needs and goals potentially in play in most waking life situations. Fixation on one goal alone, or working towards the satisfaction of one goal at a time, is not a great strategy for flourishing. For, first, if one gets stuck on a difficult goal, or if it becomes apparent i. And, second, in many situations progress towards multiple goals at once is possible.

All one needs is the capacity to divide attention somewhat, or the capacity to hold multiple goals in mind—or at least within some accessible place—and one might waste much less time. Notice, further, that the above points may hold even if dividing the mind amongst multiple goals leads to performance decrements. Perfect performance is not always required. So long as mediocre performance allows one to satisfy goals and needs, accepting mediocre performance will be a good strategy. Second, explicit cognitive control already does contain such an operation.

Sometimes a task becomes too effortful, too uncomfortable, or too boring. Sometimes—after one has just awakened from a long nap, e. In such cases performing a search for a high-value goal is a familiar operation that we perform explicitly. In other cases, we do not leave behind the current task, but we rather utilize deliberation, prospection, imagination, and other processes in order to find sub-goals, or means to achieve the goal that is currently structuring behavior.

These modes of exploration towards discovery of a high-value goal are explicit. Our question here is whether the cognitive control system implicitly—i. The proposal is that it does. First, this proposal offers an explanation for the initiation of mind wandering episodes. But they do frequently occur. One possible explanation is that the agent necessarily loses control in these instances.

That characterizes the initiation of a mind wandering episode as random. A better explanation, I submit, is that while the initiation of a mind wandering episode is, in one sense, a failure—a failure of the current goal and task set to persist—it is, in another sense, a smart move. It is smart because it results from a cognitive control system that is more or less constantly attempting to determine the value of selecting packages of control signals, and that will act when discrepancies in value are calculated.

Note, incidentally, that this could be extended to cases in which the agent is pursuing no particular goal, or has no current task. The system need not always compare value between goals. It might be useful, e. If agents associate one type of environment—a party, e. The fact that the initiation of mind wandering episodes is smart helps to additionally explain a second fact, namely, that agents with higher levels of cognitive control mind wander more frequently when the current task is easy or non-rewarding.

This is not to deny that mind wandering episodes may sometimes be initiated by affectively salient stimuli, or other distractors. Nor is it to deny the existence of completely unguided, or otherwise guided, episodes of mind wandering. I am not in a position to deny that, e. It may very well be—indeed it seems plausible—that only some cases of unintentional mind wandering are controlled in the way I here propose.

Note, however, that even if this is right, the cognitive control system may be able to interact with uncontrolled mind wandering processes. In some cases, uncontrolled mind wandering could be commandeered if a valuable goal suggests itself.

Third, this proposal offers an explanation for the fact that mind wandering episodes tend to go to other goals the agent possesses. This is a natural place for a process to go if that process is structured by an aim to find a more rewarding goal than the one from which the agent has just disengaged.

For it will be much more cost-effective to find existent goals, perhaps by querying memory, than to explore the environment and to construct entirely new goals although of course this may happen, especially when the environment easily affords novel and rewarding goals. Fourth, this proposal might be integrated with extant explanations of aspects of mind wandering. Consider, e. As Smallwood notes, the decoupling hypothesis does not seek to explain the initiation of mind wandering.

The cognitive control proposal is consistent with it. That is, the proposal is consistent with domain-general resources being deployed to assist mind wandering episodes. The main comment I wish to make here is that the decoupling hypothesis becomes more plausible, and data on the deployment of domain-general resources in mind wandering more transparent, if the entire process of mind wandering can be seen as goal-directed, where the goal is set by the cognitive control system.

This proposal is also consistent with work on the recruitment of neural areas during mind wandering. Christoff et al. The cognitive control proposal adds the possibility that executive network recruitment is associated with the goal-directed nature of at least some unintentional mind wandering.

Consider, further, recent work on the dynamics of mind wandering. In a recent review, Christoff et al. They seek, instead, to offer a taxonomy of thought-types in terms of their dynamics—of how they operate over time. They propose two dimensions along which the dynamics of thought may be influenced. The paradigm here is the intentional generation of a deliberative process, or the intentional maintenance of attention on a task. There are many ways thought may be automatically distracted—Christoff et al.

They place mind wandering near other types of spontaneous thought in the two-dimensional space: Within our framework, mind-wandering can be defined as a special case of spontaneous thought that tends to be more-deliberately constrained than dreaming, but less-deliberately constrained than creative thinking and goal-directed thought.

In addition, mind-wandering can be clearly distinguished from rumination and other types of thought that are marked by a high degree of automatic constraints, such as obsessive thought. Now, this is not an explanation of why the mind wanders. It is, instead, a mapping of mind wandering onto a broader taxonomy of cognitive kinds, with special attention given to other modes of spontaneous thought.

This taxonomy is useful for a number of reasons. For example, Christoff et al. So they say, e. Such mapping work from aspects of spontaneous thought onto activity patterns in large-scale brain networks affords fruitful suggestions for future study of the kinds of psychological patterns and activities that characterize mind wandering over time.

But there are possibilities and explanations that this approach does not yet address, and that potentially have consequences for the taxonomy of cognitive kinds that they offer. The difference is supposed to be a movement along the dimension of flexible, goal-directed constraints, with creative thinking requiring more cognitive control.

But they note that creative thinking seems more complex than this: Creative thinking may be unique among other spontaneous-thought processes because it may involve dynamic shifts between the two ends of the spectrum of constraints.

Box 1, I suggest that mind wandering is similarly complex. If the cognitive control proposal is correct, then in at least some cases mind wandering is initiated by processes of cognitive control, even though the goal driving mind wandering is not set explicitly by the agent.

This could be captured by adding layers onto Christoff et al. And these deeper explanations at each place could be expected to bear fruit for understanding the dynamics of spontaneous thought. In particular, we might hope to find patterns in the neural dynamics that are predictive of the onset as well as the termination of mind wandering episodes, and that differentiate it from dreaming, creative thought, and perhaps from rumination.

If the cognitive control proposal is correct, one task would be to map these patterns onto the expected value calculations the cognitive control system is performing.

We would expect the dynamics of mind wandering to reflect the initiation of a search for a more rewarding goal, and to reflect attempts to make progress on this search.

The cognitive control proposal makes predictions. Confirmation of these would be good news; disconfirmation would be bad news. First, given the explanation offered for the initiation of mind wandering episodes, the proposal predicts that increases in reward for satisfying an occurrent goal would correlate with decreases in propensity to mind wander.

Paradigms that have established this result could be used to test for the place of mind wandering in the behavioral data. Second, the proposal predicts that increases in reward for non-occurrent goals the agent possesses would increase mind wandering. We have already seen that reminding agents of goals they possess, or of goals they will soon need to attempt to satisfy, leads to more mind wandering in the direction of these goals.

The prediction here is more specific. If one were to, e. Third, this proposal draws upon a view of the cognitive control system on which the learning of values associated with goals, and the learning of values associated with stimuli features predictive of goals, is crucial. So the proposal, plus plausible assumptions about reinforcement learning processes, predicts that it is possible to train participants to associate stimuli with certain goals, and that registration of such stimuli would generate mind wandering to the degree that the associated goal is rewarding.

Very costly goals would produce little mind wandering. Cheap but rewarding goals would produce more. And it may be possible to extend this result. It depends on what the agent associates with rewarding goals. Above I suggested that the system need not always compare value between explicit goals, and that the value computation might include an association between expected levels of reward and particular environments.

If so, simply placing an agent in such environments would manipulate levels of unintentional mind wandering. It may be useful to distinguish predictions this proposal makes from a related proposal: the current concerns hypothesis. The current concerns hypothesis for which, see Klinger et al.

This proposal is distinct from mine in the following ways. First, I propose a specific mechanism, connected with recent modeling work in cognitive control, to explain the onset of mind wandering.

Thus far, of course, the proposal can be seen as a specification of the current concerns hypothesis. So the cognitive control proposal makes predictions the current concerns hypothesis does not.

So we should, e. Indeed, if the environment is expected to contain valuable options, one would predict that this is where attention will go, rather than to any internal space of concerns. This is not to deny that mind wandering represents a failure in some sense. McVay and Kane b have argued that mind wandering represents an executive control failure.

The possibility I am raising is that failures of goal-maintenance could in another sense be successes of a different process. Indeed, perhaps processes of goal-maintenance are closely related to the value-based process of estimating the expected value of continuing on some task, or of searching for a new task, that I propose underlies unintentional mind wandering.

In sum, the proposal is plausible on its face. The proposal may also contribute to explanations of the dynamics of mind wandering. The predictions this proposal makes are testable, and work in this direction might take steps towards further integrating knowledge of how cognitive control works with knowledge of how mind wandering works.

I wish finally to relate this proposal to two leading philosophical accounts of mind wandering. Both of these accounts aim to capture mind wandering quite generally. I have noted in Mind wandering section that this is not my aim. Here, I want only to discuss implications for these more general accounts of mind wandering, if the cognitive control proposal about unintentional mind wandering is on track.

I turn first to Thomas Metzinger This is a technical notion for Metzinger, and he considers it essential: mind wandering, for Metzinger, essentially involves a loss of mental autonomy. This ability can be a form of rational self-control, which is based on reasons, beliefs, and conceptual thought, but it does not have to be. This does not mean that they actually are terminated, it just means that the ability, the functional potential, is given and that the person has knowledge of this fact.

M-autonomy is the capacity for causal self-determination on the mental level. This led some scientists to question what is happening in the brain when we make mistakes. They specifically measured something called the feedback error-related negativity ERP component, which gives scientists an idea of how closely we are monitoring the accuracy of our responses when we perform a task.

The scientists found that the feedback error-related negativity ERP component was reduced during mind wandering compared with on-task periods, as shown in Figure 3B. This suggests that mind wandering negatively affects our ability to monitor our performance and adjust our behavior, making it more likely that we will make mistakes [ 4 ]. All of these studies provide evidence supporting the hypothesis that when the mind wanders, our responses to what is going on in the environment around us are disrupted.

At this point, you may wonder: are all responses to the world around us impaired during mind wandering? This seems unlikely, because we are usually quite capable of responding to the external environment even when we mind wander. For example, even though we may mind wander a lot while walking, most of us rarely bump into things as we walk from place to place.

A group of scientists asked the same question and looked specifically at whether we can still pay attention to our environment at some level even when we are mind wandering. To test this question, research volunteers were asked to read a book while they were listening to some tones unrelated to the book. Most of the tones were identical, but among these identical tones was rare and different tone that naturally grabbed the attention of the volunteers.

These scientists found that the volunteers paid just as much attention to this rare tone when they were mind wandering compared to when they were on task.

In other words, our minds appear to be quite smart about which attention processes to disrupt and which processes to preserve during mind wandering. Under normal circumstances, our minds ignore some of the ordinary events in our environment in order for us to maintain a train of thought. However, when an unexpected event occurs in the environment, one that is potentially dangerous, our brain knows to shift our attention to the external environment so that we can respond to the potentially dangerous event.

Imagine walking down the street and thinking about the movie you want to watch this weekend. While doing this, you may not clearly perceive the noise of the car engines or the pedestrians chatting around you. However, if a car suddenly honks loudly, you will hear the honk immediately, which will snap you out of your mind wandering.

Therefore, even when the mind is wandering, we are still clever about what we ignore and what we pay attention to in the external environment, allowing us to smartly respond to the unusual, or potentially dangerous, events that may require us to focus our attention back on the external environment. Maybe it was this default mode network that kept barging in during my meditation, interfering with my ability to keep my attention focused.

I wondered if I could test this scientifically. Then they would return their focus to the breath as usual, and the practice would continue.

As they did so, we collected MRI data showing which brain regions were active before, during, or after the button press that corresponded to various mental states. Then when participants became aware of this mind-wandering, brain regions related to the detection of salient or relevant events came online. After that, areas of the executive brain network took over, re-directing and maintaining attention on the chosen object.

And all of this occurred within 12 seconds around those button presses. Looking at activity in these brain networks this way suggests that when you catch your mind wandering, you are going through a process of recognizing, and shifting out of, default mode processing by engaging numerous attention networks. Understanding the way the brain alternates between focused and distracted states has implications for a wide variety of everyday tasks.

What are other practical implications of this knowledge? Recent behavioral research shows that practicing meditation trains various aspects of attention.

Studies show that meditation training not only improves working memory and fluid intelligence , but even standardized test scores. Without mind-wandering to derail your attempts to remain focused, how could you train the skills of watching your mind and controlling your attention?