
Man daydreaming
This question was examined in a paper by Clayton Critcher and Tom Gilovich in the September, 2010 issue of Personality and Social Psychology Bulletin.

Man daydreaming
This question was examined in a paper by Clayton Critcher and Tom Gilovich in the September, 2010 issue of Personality and Social Psychology Bulletin.
How might mind wandering make you think that you are bored? Perhaps it depends on what you are thinking about. For example, if you start thinking about positive things, then you might think that you are daydreaming about pleasant things because the task you are supposed to be doing is boring. Often, when your mind wanders to negative things, it is because those negative things are bothering you, and you can't help thinking about them. So you might assume that negative thoughts come to you whether you want them to or not, and so daydreaming about negative things might not be caused by boredom.
Another possibility, though, is that you are most likely to think that daydreaming is a signal that a task is boring when you think about the kinds of things you could be doing rather than that task. So, when you are sitting in a class or lecture, you might be most likely to interpret your mind wandering as a symptom of boredom if you start thinking about other things you could be doing rather than sitting in that class.

Boredom
Similarly, if people wrote about things they could be doing instead of being in an experiment, their daydreams tended to be about things they could be doing at that moment. If people wrote about things they had done in the past, then their daydreams tended to be about things in the past.
After doing this writing, people were asked to do something moderately interesting like doing a jigsaw puzzle or a crossword puzzle. Later, they were asked how much they enjoyed doing the puzzle.
The results suggest that people use what they daydream about to help decide whether they are bored. They said they found the puzzle least interesting when they daydreamed about positive things they could be doing at that moment. So, if they did the puzzle and their mind wandered to other fun things they could be doing instead, then they assumed that they must be bored with the puzzle.
Another interesting aspect of these experiments is that in one study people were asked to focus on the relationship between what they wrote about at the beginning of the study and their thoughts later. These people were more likely to realize that what they daydreamed about was affected by what they wrote about. For these people, daydreaming about positive things they could be doing did not make them think they were bored by the puzzle.
In the end, you should remember that your mind wanders all the time. It can be difficult to focus attention on one task for a long period of time. And there are many factors that can affect what you think about when you daydream. That means that you should not always assume that daydreams are a sign that you are bored. They might just be a sign that you have a lot on your mind.
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