How Pain Distracts The Brain

July 5, 2007

Anybody who’s tried to concentrate on work while suffering a headache knows that pain compellingly commands attention—which is how evolution helped ensure survival in a painful world. Now, researchers have pinpointed the brain region responsible for pain’s ability to affect cognitive processing. They have found that this pain-related brain region is distinct from the one involved in cognitive processing interference due to a distracting memory task.

Ulrike Bingel and colleagues at the University Medical Center Hamburg-Eppendorf published their discovery in the July 5, 2007 issue of the journal Neuron, published by Cell Press.

To search for the region responsible for pain’s ability to usurp attention, the researchers asked volunteers to perform a cognitive task involving distinguishing images, as well as a working memory task involving remembering images. The researchers asked the volunteers to perform the tasks as they experienced different levels of pain caused by the zapping of their hands by a harmless laser beam.

During these tests, the volunteers’ brains were scanned using functional magnetic resonance imaging (fMRI). In this widely used analytical technique, harmless magnetic fields and radio waves are used to scan the brain to determine blood flow across regions, which reflects brain activity.

The researchers’ experiments identified a brain region called the lateral occipital complex (LOC) as the cognitive-related area affected by both “working memory load” and pain. This finding was expected, since the LOC is known to be involved in processing images.

The researchers next sought to identify the brain region by which pain affects the functioning of the LOC. They theorized that the best candidate for this region was one called the rostral anterior cingulate cortex (rACC). This region is known to be involved in the brain’s processing of pain, and it is part of the anterior cingulate cortex, which plays an important role in “executive” functions such as attentional control. These structures are located deep in the brain in the region of connection between the two hemispheres.

Indeed, the researchers’ fMRI scans indicated that the rACC is, indeed, the brain center through which pain influences the LOC. By contrast, they found a working memory load affects the LOC through a different region, the inferior parietal cortex.

The researchers noted that the modulation of visual processing by pain that they observed in their fMRI studies is behaviorally relevant, because as their fMRI scans showed pain affecting the LOC, they also observed a parallel impairment of accuracy in subjects’ recognition of the images.

Source: Cell Press

Explore further: Ultrasound and algorithms to diagnose bacterial meningitis in babies

Related Stories

What is the best way to kill a cane toad?

May 26, 2015

Like many pests, cane toads are killed in their thousands in Australia every year, especially by community-based 'toad-busting' groups. New research has now revealed the most humane way to do it.

Snakes in evolutionary arms race with poisonous newt

November 17, 2014

The rough-skinned newt is easily one of the most toxic animals on the planet, yet the common garter snake routinely eats it. How does a newt which produces enough toxin to kill several grown humans almost immediately manage ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

(PhysOrg.com) -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.