APS conference--2008

[Jon Newman]

Information about the upcoming APS conference is becoming available and registration is open. I'll post again when I notice that they have posted their courses and descriptions.

APS Annual Scientific Meeting--2008 (http://www.ampainsoc.org/meeting/)

[Jon Newman]

The course descriptions are available to read now. There are some very intriguing titles and speakers as usual.

Thursday (http://www.ampainsoc.org/meeting/annual_08/prog_desc_thurs.htm)

Friday (http://www.ampainsoc.org/meeting/annual_08/prog_desc_fri.htm)

Saturday (http://www.ampainsoc.org/meeting/annual_08/prog_desc_sat.htm)

These courses are always well done.

[Jon Newman]

The registration list of conference attendees is confusing in that many of the registrants don't have any title listed after their names, including me. I'm not sure what you have to do to get your title to appear (I checked the "physical therapist" box when I registered.) Regardless, there are at least 8 PTs at the conference this year which is encouraging.

If there are any SomaSimple readers at the conference that would like to chime in here, I'm sure you'll find an audience interested in your thoughts. I'll add my own as I'm inspired.

[Jon Newman]

The keynote address, The Neurobiology of Pain, was given by Allan Basbaum (http://anatomy.ucsf.edu/BasbaumFaculty6.html) this year.

Here (http://www.pnas.org/cgi/reprint/99/23/15148.pdf?ck=nck) is a link to one of the papers referenced in his talk. It was a great talk and very exciting. I'll share some of the findings, as I understood them, in a later post.

[Jon Newman]

Basically these researchers have figured out a way of tracing nerve pathways. Additionally, they were able (in mice) to demonstrate that different nerve pathways go to different areas of the brain which in turn has behavioral implications. For example, neurons in lamina I of the spinal cord project to the thalamus (not only, but not to the amygdala) while lamina II neurons project to the amygdala (not only, but not to the thalamus). The former are peptide specific neurons while those in lamina II are not.

It seems, in mice, the thalamus can be considered to be associated with peptide specific neurons and sensory discrimination while the amygdala is associated with non-peptide specific neurons and affective/motivational processing. Thus there is some pathway specificity similar to the boy near the fire as depicted by Descartes.

Allan wove the story together with anecdotes about Ron Melzack and Patrick Wall and pondered what Patrick Wall might think of these findings. I think he'd be excited about this line of work as well as to see what they can discover about primates.

If anyone else attended the keynote address and wants to clarify anything I wrote (i.e. correct any misinterpretation), please do.

[Diane]

Thanks for posting about this Jon. A.D. (Bud) Craig is one of the biggest proponents of labelled line "specificity" theory, testing its limits, checking out where different paths converge in the insula. It definitely is exciting.

I still think though, (along the lines of neuromatrix theory) that if Descartes' boy with the foot in the fire were trying to fight off an attacking mountain lion at the same time, he might not feel the foot until later.

[Jon Newman]

Hi Diane,

I think that beside simply increasing our understanding of the neurobiology of pain the implications of the research are more important for pharmacology and possibly gene therapy.
You're probably correct about the fighting off the lion thing but once the lion is gone and the boy is back to roasting marshmallows, the pain will be back. On the other hand, the researchers were able to destroy the lamina two pathways (in mice) and they had no response to heated paws, lion or not.

[Jon Newman]

I can't find that the following guidelines have been posted or discussed anyplace. It seems to me that they probably have and I just missed it. I attended one of the three talks about these guidelines before heading over to hear about biofeedback.

Diagnosis and Treatment of Low Back Pain: A Joint Clinical Practice Guideline from the American College of Physicians and the American Pain Society (http://www.annals.org/cgi/content/full/147/7/478)


People interested in the above may also be interested in this (http://www.somasimple.com/forums/showthread.php?t=4711) and this (http://www.somasimple.com/forums/showthread.php?t=4715&highlight=guidelines)

[Jon Newman]

One of symposia today was Effects of Aging and Comorbidity on Pain Processing: Clinical and Preclinical Studies. Debra Weiner's (http://www.upmc.com/Communications/MediaRelations/UPMCExperts/BySubject/A/Aging/WeinerDebra.htm) talk was very interesting. She introduced a concept that isn't so new as much as the term used to describe it. Actually, the term isn't new either but it was new to me.

Pain homeostenosis = constriction of an organism’s ability to effectively respond to pain-associated stress (Resnick NM. In: Harrison’s Principles of Internal Medicine, 1994
Karp et al. British J Anaesth 2008, in press)

This is how I interpret "adaptive potential" of an organism. She discussed that a bit but then went on to discuss dementia-associated changes in pain processing and expression. I'll write more about it a bit later. My wife is coming in and she just got stung by a Stingray (http://en.wikipedia.org/wiki/Stingray) so I'm off to attend.

[EricM]

Ouch! I'm assuming that might be painful. Hope she's OK.
Thanks for bringing us updates from the conference Jon.
Here's a visual description of homeostenosis (http://www.ouhsc.edu/geriatricmedicine/Education/Homeostenosis/HomeostenosisNew_Interpretation_of_Homeosteno.htm).

[Jon Newman]

Michelle is fine except for a puncture wound in her ankle and some brush evoked allodynia; temporary we hope/expect. And we thought ticks were bad.

Back to the conference--Following a short discussion about homeostenosis and some discouraging statistics about the prevalence of dementia Debra covered a variety of research findings about pain in people with dementia.

Research Data

– Dementia is associated with increased cerebral and facial activity in acute experimental pain.

– Physiological parameters of “distress” may be blunted in those with dementia

– Some traditional “pain” behaviors lack validity in older adults with dementia.

Clinical Implications

– Individual pain signatures should be identified and documented in those with dementia in order to afford assessment of meaningful response to pain treatment.

The idea of a "pain signature" is interesting.

On the topic of facial activity, Debra cited this study (http://www.psichiatria24x7.it/news/detail.jhtml;jsessionid=1DR3M2BG0OKHSCUCERDBXCQ?itemname=c0221371.7wh0&parentSite=www.psychiatry24x7.com). I also found this one (http://www.ingentaconnect.com/content/bsc/pme/2007/00000008/00000008/art00010).

[Jon Newman]

Another talk in that symposium was by Robert Yezierski (http://www.painresearch.ufl.edu/html/yezierski__robert_p_.html). He's doing some interesting research with rats. It's important to understand the basic experiment before understanding the aging bit. So consider a look at this study (http://www.ncbi.nlm.nih.gov/pubmed/18378404?dopt=AbstractPlus&holding=f1000,f1000m,isrctn)(abstract). Or at least consider this bit from the abstract:

Skin temperature recordings from the forepaws and contralateral hind paw during 44.5 degrees C stimulation of the left hind paw provided an indirect measure of cutaneous blood flow in formalin- and saline-injected animals. Normal reductions in skin temperature during thermal stimulation were attenuated (nearly eliminated) at 1 and 2 weeks after formalin injection and partially recovered by 10 weeks. Thus, formalin-induced tissue injury produced a long-term secondary hyperalgesia, accompanied by a reduced sympathetic responsivity. The similar time-course for these phenomena suggests that there are mechanistic linkages between focal injury, autonomic dysregulation and enhanced pain sensitivity.

Subsequent studies with normal (no formalin injection) older rats show a response profile similar to that of the younger formalin injected rats (especially those 2 weeks after injection.) This suggest that the baseline response of older rats is different than that of younger rat. One implication of this is that most rat/mouse research is done on younger rodents and perhaps a more diverse population is important to study.

[Jon Newman]

Some random notes I took.

Dennis Turk has a new study (http://www.ncbi.nlm.nih.gov/pubmed/18417291) that looks interesting.

Steven Cohen had a Haper's Index type statistic stating that 1:1:2 is the ratio of good guys:bad guys:innocent bystanders harmed in the Iraq War (or OIF officially.)

From Roger Chou: the best predictor of cancer in people presenting with low back pain is a previous history of cancer and an elevated ESR.

From Joseph Riley--a quote from Mark Twain: "Age is in the mind. The trick is not to let it creep down into the body."

From Mitchell Max whose lecture was so far over my head that I'm surprised I wrote anything down at all: The p-value necessary to impress researchers of genome wide associations is 1 x 10-7!

From Sean Mackey: I learned about Granger causality mapping (http://www.scholarpedia.org/article/Granger_causality) and to consider the difference between distraction and emotional reappraisal. (http://www.columbia.edu/%7Eko2132/pdf/Ochsner_Better_or_Worse.pdf)