Pain and the mind
Latest
May 2008
More pain for the poorer, the less-educated and the solitary
A 24-hour diary survey of
4,000 Americans has found that over a quarter (28%) were in pain at any given
moment and those with less education and lower income spent more of their time
in pain. The average pain rating was twice as high for those in households with
annual incomes below $30,000 as for those in households with incomes above
$100,000, and those in the lower-income households spent almost 20% of their
time in moderate to severe pain, compared with less than 8% for those in the
higher-income households. Workers in blue collar jobs reported higher
occurrences and more severe pain than did those in white collar jobs. For blue
collar workers, pain was lower when they were off work than when they were
working. People were more likely to feel pain when they were alone compared with
when they were with friends or a spouse. In addition, those in pain spent a
disproportionate amount of their time -- almost 25% -- watching television,
compared with 16% for others.
http://www.sciencedaily.com/releases/2008/05/080502081604.htm
Treating pain
February 2008
Patients with larger social networks may fare better after an operation
A study of over 600 patients undergoing major thoracic or abdominal
operations has found that patients with a large support network of family
and friends report feeling less pain and anxiety prior to having a surgical
procedure, which can have a substantially positive impact on their
postoperative recovery.
http://www.physorg.com/news122039294.html
June 2007
Hope for sufferers of chronic pain
Why does chronic pain sometimes linger long after the
precipitating injuries have healed? A study has now found a key cause
appears to be an old memory trace that essentially gets stuck in the
prefrontal cortex. Identifying this has led to identifying a drug that may
be effective against such chronic pain. The drug controls persistent nerve
pain by targeting the part of the brain that experiences the emotional
suffering of pain, and has been used to treat phobic behavior. Animal
studies appear to show animals pain free 30 days after the last dose of a
30-day regime. The research also found that the longer a person has been
suffering from chronic pain, the more activity in the prefrontal cortex — to
such a degree that the researcher could predict with 90% accuracy how many
years a person had been living in that pain without even asking them the
question.
http://www.eurekalert.org/pub_releases/2007-06/nu-omt060407.php
November 2006
Virtual reality system combats phantom-limb pain
Amputees who experience
"phantom limb pain" could find relief with a 3D virtual reality system that
creates the illusion that they can once again control their missing limb.
The idea follows the discovery by Vilayanur Ramachandran that a "mirror box"
that creates the visual illusion of two hands for people who actually only have
one reduced phantom limb pain. Phantom limb pain is thought to relate to a
"rewiring" of different parts of the brain associated with physical stimulus.
Signals from other parts of the body may inadvertently be fed into parts of the
brain that relate to a missing limb. These techniques may work by somehow
activating nerve pathways in the brain that were linked to the missing limb, but
that became dormant after its loss.
http://www.newscientisttech.com/article/dn10579?DCMP=NLC-nletter&nsref=dn10579
October 2006
Why trying to control pain can be a double-edged sword
An imaging study
reveals why a feeling of control helps us reduce pain: when people feel that
they can control their pain, the anterolateral prefrontal cortex, which is
associated with successful coping with feelings of anxiety. is activated.
Moreover, when faced with pain beyond their control, people who tend to feel
more in control of their own lives show a lower response in this area,
indicating that they are less effective in coping with pain than those who don't
expect to have control. The findings support the practice of "acceptance-based
therapy" whereby doctors focus on training patients to cope with the pain rather
than attempting to make the pain go away.
http://www.sciencedaily.com/releases/2006/10/061031191327.htm
August 2006
Guided imagery helps chronic pain
A small study of
chronic pain sufferers has found that a technique that involved listening to a
seven-minute audio tape to help them relax, then focusing on the sensory images
their pain evoked, then being guided to change the sensory images, made the pain
more tolerable or easier to control.
http://www.sciencedaily.com/releases/2006/08/060828211705.htm
June 2006
Music helps pain
A review of 51 clinical
studies has concluded that patients exposed to music
rate their pain as less intense and even use lower doses of painkillers. The
average was only a .5 drop on a 0-10 scale, but the effect varies between
individuals, and after all there are no side effects to playing music.
http://www.sciencentral.com/articles/view.php3?article_id=218392834
Music helps those with chronic pain
A study involving 60 people with chronic pain has found that listening to music could reduce the pain by up to 21% and depression by up to 25%, as well as helping people feel more in control of their pain and less disabled by their condition. Participants listened to music for an hour every day for a week.
Technique for teaching people to control chronic pain
ScienCentral have an interesting article about a new technique for teaching people to control their pain. Several people with chronic pain who were able to watch their own brain activity while in a MRI gained a certain control over their perception of pain. Not all were able to learn this, and the technique is currently far too expensive and involved for general use, but it does highlight the fact that pain is a product of our brain, and offer promise for those who suffer from chronic pain.
Controlling chronic pain mentally
And Nature reports on a recent study demonstrating that many people with chronic pain can be taught to markedly reduce their own discomfort simply by controlling their thoughts.
The complexity of our experience of pain
And if you're interested in the complexity of our experience of pain (and it is a complex issue), check out this article on what imaging studies have shown us.
August 2004
Friends Makes Wounds Heal Faster
A hamster study has found that
skin wounds healed nearly twice as fast in hamsters paired with a sibling. These
animals also produced less of the stress hormone cortisol than unpaired
hamsters. Socially isolated hamsters treated with oxytocin (the ‘bonding’
hormone) also healed faster than untreated lone animals, but not as fast as
those who had social support. However, lone animals who had their adrenal
glands removed (this is the main source of cortisol) healed at the same rate as
paired hamsters, indicating that it’s the reduction on stress that is the
benefit in social support. A further experiment also revealed that paired
hamsters who were treated with something that blocked oxytocin production showed
delayed healing, suggesting that the production of oxytocin is also a benefit of
social support.
http://www.sciencedaily.com/releases/2004/08/040804083847.htm
Virtual reality changes how the brain physically registers pain
Virtual reality appears to dramatically change how the brain physically registers pain, not just how people subjected to pain perceive the incoming signals, according to a new study by a group of University of Washington researchers.
Treatment of chronic pain
Researchers have shown how the brain subconsciously remembers details around past dangers. While lying in a functional magnetic resonance brain scanner 14 patients were shown a series of abstract pictures followed by a one-second electric shock - equivalent to a pin-prick. Afterwards many of the volunteers could not consciously recall the sequence of images, but the scanner revealed that two key areas, the ventral striatum and part of the cerebral cortex, were working together to figure out what was coming next. The researchers think blocking this system could help treat chronic pain by interrupting such a brain process.
Individual differences
May 2008
More pain for the poorer, the less-educated and the solitary
A 24-hour diary survey of
4,000 Americans has found that over a quarter (28%) were in pain at any given
moment and those with less education and lower income spent more of their time
in pain. The average pain rating was twice as high for those in households with
annual incomes below $30,000 as for those in households with incomes above
$100,000, and those in the lower-income households spent almost 20% of their
time in moderate to severe pain, compared with less than 8% for those in the
higher-income households. Workers in blue collar jobs reported higher
occurrences and more severe pain than did those in white collar jobs. For blue
collar workers, pain was lower when they were off work than when they were
working. People were more likely to feel pain when they were alone compared with
when they were with friends or a spouse. In addition, those in pain spent a
disproportionate amount of their time -- almost 25% -- watching television,
compared with 16% for others.
http://www.sciencedaily.com/releases/2008/05/080502081604.htm
May 2006
Anticipation worsens pain
A brain scanning study
has looked at brain activity when people were informed that a shock to their
feet was coming and how big it would be, compared to being given a choice
between a big shock with a short time delay, or a smaller shock that they had to
wait longer to experience. While almost everyone, given a choice, wanted to get
the shock over with straight away, only 9 of the 32 subjects dreaded the shock
so much that they chose a stronger blast sooner over a milder one later on.
These nine showed heightened activity in the area of the brain responsible for
perceiving pain, especially in the part linked to attention, but not in the part
involving fear and anxiety. In other words, the more dread bothered someone, the
more attention the pain-sensing parts of the brain were paying to the wait.
http://www.nature.com/news/2006/060501/full/060501-9.html
Individual differences in how we anticipate pain
Another study in neuroeconomics -- using brain scans to investigate how people make decisions -- has revealed that some people react to the anticipation of pain as if it was the pain itself. These people would sooner have a stronger shock immediately than wait a while for a milder shock -- a choice that is more understandable now we've seen that there is increased brain activity in the area of the brain that perceives pain. (yahoo report; Nature report)
What's happening in the brain
March 2008
Similarities and differences between experiencing and observing pain
A number of studies have found that perceiving others in pain and experiencing pain oneself involve overlapping neural systems. A new study reported online March 15 in Social Cognitive and Affective Neuroscience shows that while both experiencing heat pain and watching videos of other individuals experiencing injuries activated the anterior cingulate cortex and anterior insula, pain to oneself also involved anterior and mid insula regions implicated in interoception and nociception, while observed pain activated frontal, premotor, parietal and amygdala regions implicated in emotional learning and processing social cues. Also, levels of anxiety correlated with activity in the rostral lateral prefrontal cortex when observing others, but not when experiencing pain oneself. http://scan.oxfordjournals.org/cgi/content/abstract/3/2/144
October 2007
Why pain commands your attention
Imaging research has now
explained why it’s so hard to concentrate when you’ve got a splitting
headache: the rostral anterior cingulate cortex, part of the anterior
cingulate cortex, which plays an important role in “executive” functions
such as attentional control, is involved in the brain’s processing of pain.
In the case of visual recognition of objects, which is impaired when you’re
experiencing pain, the rostral anterior cingulate influences the lateral
occipital complex, which is involved in the processing of images.
http://www.eurekalert.org/pub_releases/2007-07/cp-hpd062807.php
Brain's 'pleasure chemical' also involved in response to pain
Dopamine is thought of as the brain's "pleasure chemical," sending signals
between brain cells in a way that rewards a person or animal for one activity or
another. It’s also been implicated in drug addiction. An imaging study has now
revealed that the brain's dopamine system is also highly active when someone
experiences pain -- and that this response varies between individuals in a way
that relates directly to how the pain makes them feel. The action of dopamine in
the basal ganglia had different effects in different sub-regions. In the nucleus
accumbens (the same region implicated in drug addiction), higher dopamine was
associated with higher ratings of distress and fear — the emotional correlates
of pain. In the putamen and caudate nucleus, dopamine level was strongly
correlated with the rating of how intense and unpleasant the pain itself was.
The finding may help explain why people are more likely to acquire a drug
addiction during times of intense stress, and why some, but not other chronic
pain patients may be prone to developing addictions to certain pain medications.
http://www.sciencedaily.com/releases/2006/10/061019094148.htm
July 2006
On-off switch for chronic pain found
In an exciting
new discovery, researchers have discovered a protein in nerve cells that acts as
a switch for chronic pain, and have applied for a patent to develop a new class
of drugs that will block chronic pain by turning this switch off. While it's
been known for years that for chronic pain to persist, a master switch must be
turned on inside the peripheral neurons, until now the identity of this switch
has remained a mystery. The switch has now been identified as an enzyme called
protein kinase G (PKG).
http://www.sciencedaily.com/releases/2006/07/060720095621.htm
