The Brain is Busier Than We Think

In the 2014 film Lucy a drug mule played by Scarlett Johansson boosts her ability to use 100 percent of her brain when a synthetic drug leaks into her system.  Her awesome psychokinetic powers then enable revenge against her enemies.  The film built on what 65 percent of respondents in a 2013 poll believed – that we use just ten percent of our brain in daily life.  Brain-boosting drugs have been marketed to increase that percentage, though neither the film nor the drugs are based on science.  Actually, we use 100 percent of our brain. 

It just may not seem so, especially when we’re not focused on a task. For example, a 60 year-old has spent about 20 of those years sleeping.  If you add to that all the time we spend daydreaming or letting our mind wander, say when we’re bored or doing a routine task like driving to the store, we could add a few more years in which it seems that we’re just not needing most of our brain.  But the brain is not tuned out even when we think we are.  In fact, physical and mental health both depend on what our brain does when we think it’s mostly doing nothing.

When we sleep, our brain does not.  About 25 percent of those hours of sleeping are spent dreaming. Researchers suggest that REM (Rapid Eye Movement) sleep may be essential to keep the visual part of the brain’s cortex well.  Vision is the only sense we don’t think we use when we sleep, so this research argues we “see” in our dreams to keep that part of the brain healthy.  Dreaming also matters because people unable to dream enough experience everything from being groggy to digestive and mood disorders.

The brain’s hippocampus, which is essential to both memory and learning, is also active during sleep.  It takes short term memories formed while awake and turns some into long-term memories we can draw upon later.  It consolidates memories essential to learning, which is why research shows that what we study just before going to sleep is remembered better the next day.  The hippocampus also weeds out some memories, making room for new ones.

This is all going on, of course, when we might assume nothing is going on in the three pounds between our ears.

The brain is also doing more than we know when we’re awake.   Even when we’re focused on a task, we have what neuroscientists call a Default Mode Network (DN) consisting of three inter-connected parts of the brain that regularly get active, such as when our mind wanders off that task.  Maybe that wandering is thinking about a dinner date coming up or a recent encounter with a friend.  Maybe we just start daydreaming about an idyllic vacation.  That’s the DN at work. Neuroscientists speculate that it’s engaged about a third to a half of the time we’re doing a task. 

The Default Network also allows us to think about ourselves, such as our emotions.  It enables us to think about others, including what scientists call theory of mind - our ability to ascribe mental states and possible actions to others, which is essential for empathy and moral reasoning.  It also helps us recall the past and think about the future. The DN thus alternates with and complements task-focused brain activity.  It’s not an either-or.  The DN can also foster creativity when we are stuck on a problem by enabling associations from many brain regions without our conscious awareness.  Indeed, scientists estimate that brain functioning below the level of our conscious awareness accounts for up to ninety percent of our thinking.  It’s not necessarily all positive, however: excessive DN thinking about the past can foster depression and excessive DN worry about the future can foster anxiety.

So, think about your brain as a friend that helps you 100 percent of the time – and about what you can do to improve that 100 percent you rely upon.

·       Get enough sleep to promote the REM (dream) state.

·       Practice meditation, which can help you both concentrate and mind-wander in ways that complement each other.

·       View mind-wandering as potentially useful rather than a distraction.  It may enhance recalling things from memory, behaving ethically toward others and planning for the future.

·       Accept that mind-wandering, though it seems like “noise” taking you away from a task, may be unconsciously aiding your creativity in solving problems.

·       See mind-wandering and its close cousin daydreaming as ways to keep you healthy.  They can temporarily reduce stress.

Even beyond this research and these benefits, good sleep and mind-wandering are enjoyable.  In an experiment, researchers asked participants to just sit alone with their thoughts for 20 minutes, without engaging in any task, such as reading or using their phones.  Afterwards, participants reported they enjoyed mind-wandering more than they expected.

You don’t have to take a “Lucy” drug to get full use of your brain.  You already have that.

Photo Credit: John Hain@pixabay.com