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Brain Fuzz: Can Brain Scans Provide a Space-Out Way Out?

eambash's picture

If you're up all night before a big exam, or if you sleep all day before getting up to go to a big event, can your doctor tell? Sometimes the brain makes mistakes, be it because of it sleep deprivation, lack of interest, or bad concentration. Sometimes we space out, daydream, fall into a zone other than the hard-at-work zone. These space-outs cause visible effects -- just look at the papers we forgot to file, the typo we could have avoided, the kid we should've picked up after school. Aside from the visible, though, how else can we tell when the brain is doing something wrong or something outside of the ordinary?

One way, according to a study in the Proceedings of the Natural Academy of Science, is to look at an fMRI (or functional magnetic resonance imaging) scan of the brain and see just how and when the mistake is made. The report claims that a brain change actually occurs about thirty seconds before the mistake takes place. Blood flow decreases in certain areas of the frontal cortex, while other areas of the brain experience increased blood flow (1). These brain changes can account for mistakes -- even before they are made.

The brain, researchers say, reverts to a sort of primitive mode when it "spaces out." Areas of the brain known to be active during periods of rest are those seen experiencing more blood flow when the brain starts to go into this rest mode, while areas involved in making critical decisions and performing serious tasks (those in the pre-frontal cortex) receive less priority (2). This rest mode has been compared to cruise control -- the brain continues to function, but it does so with less effort and less concentration because it has become used to certain patterns.

Ideally, recognizing changes in the brain should help enable us to prevent mistakes before they happen. However, say scientists, there is no clear way to draw a positive correlation between the visible mistakes in the real world and the brain changes. Even if both happen around the same time, there could be a third factor causing both of them; the brain changes cannot be definitively said to cause the mistakes (2). MRI scanners, moreover, are way too bulky to be carried around like compasses, and the average Joe probably wouldn't benefit from confusing green-on-black graphs anyway. EEGs have been suggested as an alternative, perhaps an option for a wireless device that could help people keep track of their brain activity so that they would be able to alert themselves -- to snap themselves back into high-concentration mode -- as soon as they see their brains entering rest mode.

The potential for such a device and its accuracy is, of course, far in the future. But how can this study help us today? One way might be that if we can see our brains reacting neurologically to certain physical or emotional states we might be able to see a clearer link between our own behavior -- our ways of treating our bodies, our routines and habits, our jobs -- and the health of our brains.

Take sleep deprivation. Researchers and television specials have for years suggested a link between lack of sleep and bad concentration or poor job performance. The use of fMRIs now allows scientists to see specifically how sleep deprivation alters brain activity and, consequently, memory, learning, and everyday functioning (3). Using images of subjects brains while they performed verbal and arithmetic tasks, scientists were able to compare their brain activity to the brain activity of subjects with adequate rest. Performing the same tasks, the sleep-deprived patients had less activity in certain areas of the brain, compared with rested patients, and more activity in others (thought to be evidence of the brain "compensating" for sleepiness by moving certain tasks to areas of the brain not normally associated with performing them). In this case, when sleepier patients did worse on arithmetic questions than rested patients, scientists were able to document -- visibly and precisely -- where in the brain the mistakes originated.

Changes in brain patterns do not always have as clear an origin as in the sleep study, where sleep deprivation can be pinpointed as the cause for poor performance. What if someone has been kept awake for an uncommonly long stretch of time -- a clear case of sleep deprivation -- but is also being affected by some other stressor, such as difficult work or a monotonous, boring schedule? Can one type of fatigue be clearly differentiated from another? In one study in Chicago, researchers were able to tie a history of long shifts to mistakes made by first-year medical residents (4). Extended shifts were clearly associated with a large increase in mistakes, including mistakes leading to death. Studies such as this one show (this time without the use of brain scans) that fatigue can cause detrimental mistakes, but they also raise serious questions about the type of scientific conclusion being drawn.

Can we say for sure that the residents' fatigue was caused by the sleep lost during a long shift? What if the length of time standing on one's feet is enough to cause fatigue? Or the stress associated with life-and-death situations and stroke-of-the-minute decision-making? Or hunger from missing meals? Repetition may not be the only cause of a type of rest mode -- what if the brain "economizes" when overwhelmed too? Doctors clearly learn to function with a great deal of stress from day to day, but if they make more mistakes during a long shift, does that mean they too having a point where the stress makes the brain space out? Or is the brain doing everything it can -- except that it can't because it is sleepy? It's hard to pinpoint, in cases like this, what the true cause of the mistake is, even if we can clearly see that brain activity changes along with routines and that those brain changes can help show, visibly, when and where a mistake (or a difference in functioning) occurs.

Even if these questions cannot be clearly answered by brain scans or real-world studies alone, they can help point to more beneficial ideas and studies. For example, how can people, especially those who know they are going to be on their feet working hard all day, or those who are going to be staring at a screen in a cubicle feeling bored all day, find ways to improve their concentration and prevent, or at least deal with, changes in brain patterns? Even if we do not have a mobile device to let us know the moment our brains start to space out, perhaps we can strengthen our brain functioning in general so as to prepare for especially boring or overwhelming periods of activity. Meditation, for instance, has long been touted, and more recently been tested, as a way to improve memory and attention. MRIs show that brain regions associated with those functions are thicker in patients who meditate regularly (5). Perhaps if we all meditate for a little while, we'll be prepared when our brains decide to go a bit fuzzy! At the very least, new technology can help scientists and everyday people come to terms with the idea that our brains change along with our behavior -- even if we can't drawn a clear causal link between the two in every case.




1. ITWire. Making mistakes at work? Maybe you have a boring job!

2. BBC News. Dull jobs really do numb the mind.

3. UCSD Medical Center. Brain Activity Is Visibly Altered Following Sleep Deprivation.

4. USA Today. Long hospital shifts, sleep deprivation can kill.

5. USA Today. Say 'om': Meditation may aid in brain function.



Paul Grobstein's picture

Spacing out: source of "mistakes" and ... ?

I wonder what it is that the brain is actually doing in "cruise control"? Maybe it makes "mistakes" on one kind of task because its busy with a different kind? Maybe relevant is some work by Kalina Christoff on "mind wandering".