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Emphasizing how little we know about the brain...

Nic 57/15



*A distinct pattern of brain waves which occurs just before we make a
mistake because of a lack of attention has been discovered by scientists.*

The US and Dutch researchers say the discovery could help devise
attention-monitoring devices for workers such as air traffic control
operators.

It may also help aid new treatments for children with attention deficit
hyperactivity disorder (ADHD).

The study appears online in the journal Human Brain Mapping.

 The researchers, from the University of California, Davis, and the Donders
Institute in the Netherlands, recruited 14 students to take part in the
study, monitoring their brain activity using a recording technique called
magnetoencephalography (MEG).

Each student was asked to take part in monotonous test in which a random
number from one to nine flashed on a screen every two seconds, and they were
asked to tap a button as soon as any number except five appeared.

The test was so boring that even when a five showed up, the subjects
spontaneously hit the button an average of 40% of the time.

The researchers found that about a second before these errors were
committed, brain waves in two regions were stronger than when the subjects
correctly refrained from hitting the button.

In the back of the head (the occipital region), alpha wave activity was
about 25% stronger, and in the middle region, the sensorimotor cortex, there
was a corresponding increase in the brain's mu wave activity.

*Running on idle*

Researcher Dr Ali Mazaheri said: "The alpha and mu rhythms are what happen
when the brain runs on idle.

"Say you're sitting in a room and you close your eyes. That causes a huge
alpha rhythm to rev up in the back of your head.

"But the second you open your eyes, it drops dramatically, because now
you're looking at things and your neurons have visual input to process."

The team also found that errors triggered immediate changes in wave activity
in the front region of the brain, which appeared to drive down alpha
activity in the rear region.

Dr Mazaheri said: "It looks as if the brain is saying, 'Pay attention!' and
then reducing the likelihood of another mistake."

He said it should be possible to develop a wireless monitoring device to
read an air traffic controller's brain waves, and trigger an alert when
alpha activity begins regularly to exceed a threshold level.

A similar approach could be used to determine waning attention in children
with ADHD.

"That can help us design therapies as well as evaluate the efficacy of
various treatments, whether it's training or drugs."

Professor Nilli Lavie, of the Institute of Neurology at University College
London, said in increase in alpha brain wave activity was often associated
with sleepiness.

She said the study was interesting, but finding a practical application
could prove difficult.
She said: "The best way to tackle the problem of monotonous tasks is to
design the task to make it more visually       interesting so it is easier
to sustain attention."

http://news.bbc.co.uk/2/hi/health/7955360.stm

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