共通テスト英語 2026年度（令和8年度） 本試験 第7問
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Mind-Wandering: Lost in Thought

Rodin’s sculpture The Thinker represents a man absorbed in thought. People may wonder if he is thinking about life’s deep questions. Likewise, teachers may wonder what students sitting at their desks are thinking about—are they focusing on their schoolwork, or are they just daydreaming?

It is natural for the mind to switch between periods of focus and periods of rest. Even when we are supposed to be concentrating, we may not be paying attention to the task at hand. Scientists have found that we engage in daydreaming, also known as “mind-wandering,” approximately 50% of the time we are awake. While our minds are wandering, we are not thinking about anything special but our brains naturally come up with ideas, images, and emotions. In short, mind-wandering is a shift away from thoughts on the current task to other unrelated thoughts.

Our understanding about mind-wandering has grown over time. Past studies argued that mind-wandering was not merely a waste of time but actually quite harmful. Mind-wandering was found to negatively influence our mood, leading to work-related mistakes, traffic accidents, and even mental conditions such as depression. New research, however, shows that mind-wandering also has positive effects which can enrich our lives in various ways.

One such effect is that mind-wandering helps us generate creative ideas. In fact, some of our best ideas become apparent when our minds are wandering. To access these ideas, however, our brains sometimes require a period of time, just like eggs need time to hatch. This is called the “incubation period.”

This interval away from the problem is critical because during that time our brains are unconsciously sorting through pieces of information and associating them with the problem. This enables us to come up with a fresh solution, which appears when we least expect it, for example, when we are on a walk or taking a shower.

What is really going on in the brain when the mind wanders? Previously, the brain was thought to be in a passive state at this time. However, through neuroimaging research conducted in 2001 in the US, more than a dozen regions of the brain were found to be active during mind-wandering. These regions, as a whole, were named the Default Mode Network (DMN). Moreover, according to a study conducted in 2022 by researchers based in Norway and the Netherlands, the DMN was more active when participants were performing a low-effort task compared to a high-effort task.

How can we make use of new discoveries in brain science and increase the number of unique benefits that mind-wandering has to offer? Here are four tips to help expand your mind. First, make time for simple activities such as doing the dishes or taking a warm bath. When involved with these undemanding tasks, our mind is free to wander around. Next, we can just go outside. For example, when we are in a forest, we are able to relax in nature and our mind can more easily spread out in all directions. Another suggestion is to get enough quality sleep each night. This will not only improve our mood, but enable the brain to be more receptive to new ideas. Finally, when we wake up in the morning, we should try to notice any thoughts that occur before we get out of bed. In this half-sleep state, our mind tends to wander and our ideas can flow more freely.

We will not always be able to control all of our thoughts. However, if we are aware of when and how mind-wandering happens, we may be able to take advantage of its seemingly random nature.

Slide drafts

In the discussion session about lifestyles, some students’ habits and routines were shared on the screen. Choose the two students who are most likely to gain the benefits of mind-wandering based on the tips mentioned in the passage. [37]