What happens in the brain when you are lost in thought?
Our brains are always busily moving. Getting ready for work, talking to the boss, working on the computer—the substance varies, but the brain is also active in this part or that in a range of ways in response to it. However, we don’t work 24 hours a day, and we often daydream or stare into space. According to one theory, we spend over half the time we are awake lost in thought, but in that case, what brain activity is going on while we are lost in thought?
Default mode network: the musing brain
If you think about work or sport, we often move as part of a team. It is the same with the brain: we know that when it does something, regions of the brain form a network and operate together like a team.
There are networks in the brain corresponding to reading a book, having a conversation, and kicking a ball, but surprisingly, there is also a network for daydreaming. This is known as the default mode network, and as the name suggests, it is the brain’s activity in its default state when it is not doing anything.
The default mode network corresponding to the daydreaming state has been discussed in a number of recent studies in relation to dementia, ADHD, and other conditions in which people easily become lost in their thoughts.
Do different people have different default mode networks?
The paper I discuss today investigates default mode networks using brain waves. The experiment measured the brain waves of 15 healthy subjects over 128 channels, and investigated the differences in brain wave bands (delta, theta, alpha, beta, and gamma) between when they had their eyes closed without doing anything and when they had their eyes open.
The results showed that when subjects had their eyes closed, characteristic brain waves that seemed to represent the default mode network were observed, and more interestingly, subjects exhibited extremely large variation in their brain waves when their eyes were closed. In other words, as far as the brain patterns with eyes closed show, some people wander off with the fairies quickly while others do not, and the difference between them is considerable, and the paper suggest that this knowledge could be useful in assessing dementia and development.
I wonder what I’m like when I close my eyes, then.
Reference URL: EEG default mode network in the human brain: spectral regional field powers.
