Matthew MacKinnon MD


The Dangers of a Wandering Mind

New research reveals the connection between mind wandering and happiness.

Posted Apr 14, 2016

Christian Joudrey/Unsplash
Source: Christian Joudrey/Unsplash

You may spend up to 50% of your day lost in thought. (1)

To learn more about the wandering mind let’s examine data from a study published in the journal Science by Drs. Matthew Killingsworth and Daniel Gilbert (2).

Thought can be divided into “stimulus-dependent” and “stimulus-independent” thought. Stimulus-dependent thought has an object of focus. Due to the cumbersome nature of the term “stimulus-dependent,” I will instead use the term “focused thought” going forward. 

Focused thought is engaged when we work on a mathematical problem, critically review a past event, or when we actively plan for the future. Focused thought is engaged when we closely attend to a particular task such as raking leaves, walking down the street, or simply washing dishes.

Vashishtha Jogi/Unsplash
Source: Vashishtha Jogi/Unsplash

Stimulus-independent thought does not have a focus and often wanders from topic to topic heedless of any conscious direction. Let's call it “wandering thought.” Wandering thought uncritically darts from present sensations or emotions, to past events, to imagined future occurrences. Wandering thought is the form that likely consumes up to 50% of your day.

In their study, Drs. Killingsworth and Gilbert revealed that people are happier when engaged in focused thought than when they are engaged in wandering thought, regardless of the focus of their activity. In fact, even typically disagreeable tasks such as commuting or doing housework were associated with greater levels of happiness than any form of wandering thought.

Almost 50% of wandering thought seems to involve pleasant topics while a little more than 25% involves unpleasant topics. However, even a pleasant wandering thought that inserts itself into a given activity does not enhance an individual’s reported happiness. Unfortunately, unpleasant wandering thoughts do tend to decrease a person’s happiness when these thoughts inject themselves into an activity.

A seemingly logical explanation would be that unpleasant wandering thoughts are caused by negative moods. Yet Drs. Killingsworth and Gilbert demonstrated just the opposite, namely that wandering thought seemed to cause negative moods.

Finally, wandering thought was a stronger predictor of a person’s mood than was focused thought and the activity of focus. In other words, it seems that wandering thought may trump focused thought and activity when it comes to happiness.

Jeremy Thomas/Unsplash
Source: Jeremy Thomas/Unsplash

So what does this all mean?

Wandering thought is a byproduct of evolutionary pressure that honed the human brain into a hypothesis-testing machine. Humans have an amazing capacity to review past information and plan for future situations. Unfortunately, if not handled properly, this machinery can hurt the operator. 

In a world awash with distractions, all it takes is a cell phone chirp to derail us from a given task and open the door to wandering thought. Thankfully, there are ways of decreasing wandering thought.

Mindfulness uses the anchor of the present moment to steady a mind buffeted by distractions. There are numerous techniques that allow us to hitch our mind to the respite of a mindfulness anchor. 

How many times have you driven, taken the bus, or walked the same route to work? The first few times that you did, you were likely acutely aware of the novel sights, sounds, and smells of your surroundings. But it is likely that these details slowly receded into the backward as the route became routine. You can change this.

The next time that you are walking into work, briefly pause and complete the Five by Five exercise. The Five by Five exercise entails taking mental note of five items as perceived by each of your five senses. The exercise will purposefully engage you in focused thought and help you reconnect with your surroundings. 

Alexey Topolyanskiy/Unsplash
Source: Alexey Topolyanskiy/Unsplash

Another exercise is called the Take Ten. At some point during your day when you are feeling particularly distracted, I would challenge you to pause and take ten deep breaths. The power of this exercise is proportional to the amount of focus that you bring to your breathing. Focus on the cool sensation at the tip of your nose as you slowly inhale, the neutral point between your inhale and exhale, and the warmth upon exhale. (There are many more exercises that use mindfulness to engage focused thought, and I would recommend that the interested reader enter “mindfulness exercises” into his or her search engine of choice.)

Focused thought connects us to the here and now, while wandering thought pulls us away from it. Numerous philosophical traditions across the millennia have recognized the healing power of the present moment. Science is just now beginning to catch up with this ancient wisdom. We need not wait for any further scientific proof.

The next time that you find yourself lost in thought, pause, take a deep breath, and bring yourself back to the present moment. I would venture that you’ll be surprised by the results.

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  1. Smallwood, J., & Schooler, J. W. (2015). The science of mind wandering: empirically navigating the stream of consciousness. Annual review of psychology, 66, 487-518.
  2. Killingsworth, M. A., & Gilbert, D. T. (2010). A wandering mind is an unhappy mind. Science, 330(6006), 932-932. 
  3. Mrazek, M. D., Franklin, M. S., Phillips, D. T., Baird, B., & Schooler, J. W. (2013). Mindfulness training improves working memory capacity and GRE performance while reducing mind wandering. Psychological Science.
  4. Kane, M. J., Brown, L. H., McVay, J. C., Silvia, P. J., Myin-Germeys, I., & Kwapil, T. R. (2007). For whom the mind wanders, and when an experience-sampling study of working memory and executive control in daily life. Psychological science, 18(7), 614-621

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