Friday, February 29, 2008

What's in a Name

I stumbled upon a blog this week that has engulfed me. It is the science based medicine blog. It's authors include some of the various skeptic circles including Harriet Hall and Steven Novella among others. These are so many great conversations on this blog. But, I wanted to explore the name Science based medicine.

What is the difference between this and Evidence Based Medicine? Well, I believe little if you look at Sackett's discussion of what he meant by Evidence Based Medicine. EBM describes the use of research, clinical experience, and patient preference in clinical decision making.

All too often, however, EBM takes on an Evidence Only Medicine (as described by Nicholas Lucas) characteristic. This is where no decisions can be made without outcome based research to back it up. Of course this is a very narrow view and is impractical in the clinic.

I believe Sackett's ideas are better described by the term Science Based Medicine. This implies a decision making process consistent with the scientific method. Doesn't that sound more consistent with Sackett's aims?

Wednesday, February 27, 2008

Cory's new blog

Just a quick post to point readers in the direction of Cory's new blog and webpage, Forward Motion (see permanent link to the right). Very nice site!

Monday, February 18, 2008

Getting past fear

In reference to FABQ and physical therapy:

Cory, I have to confess up front that I've never used this questionnaire with any of my patients.

I completely concur with your conclusion:
Bottom line, change the belief about pain and you change the way a person behaves in response to pain. Change the behavior in response to pain and you can change the pain itself.
This post by Matthias also references Waddell's book and the biopsychosocial model, here.

The brain seems to be attracted to novelty, even if only the novelty of a new idea (it must find the "new idea" nonthreatening of course..). This ties in with Melzack's pain model, where the neuromatrix constantly folds in cognitive evaluative, sensory-discriminative, and motivational-affective inputs, to produce its outputs, one of which might be pain perception.

The other thing the brain finds convincing, possibly even more so, is illusion, whether visual (as with mirror therapy a la Ramachandran, or with videos a la Ehrsson and Lenggenhager and Blanke) or kinesthetic ("movement illusion" as per Collins et al) or perhaps both. (Here's a little study idea I had late last year..)

If the illusion is convincing enough to the brain, it doesn't seem to matter if the "mind" is convinced or not - people seem overwhelmingly capable of suspending any disbelief they may have. The mirror therapy is sufficient proof of that - the amputee patient is fully aware they are looking at their remaining limb move in a mirror image, yet the illusion still works. A large-scale trial of mirror therapy is currently underway at Walter Reed army hospital.

It looks to me like our PT work will just keep on evolving and get easier and easier, the more the brain/ nervous system comes to be understood and appreciated, the more we learn to understand how it perceives and constructs a reality for itself and the human body it is meshed with.

Sunday, February 17, 2008

FABQ and physical therapy

Another study on the FABQ (fear avoidance behavior questionnaire) in physical therapy was published in this month's JOSPT. The purpose of the study was to more specifically delineate the significance of the 2 portions of the test, look at predictive ability of each, and determine the score at which the test became predictive. Very exciting, I know.

The FABQ was developed by Gordon Waddell, of biopsychosocial model fame, and is as a test to determine the fear based pain behavior of patients. It is built on the premise that people in pain exist on a spectrum from "confronters" to "avoiders" when it comes to pain. Avoiders are more likely to continue to be in pain. It has been shown to be one of the better tools at identifying who is more and less likely to have their pain become long standing.

What I find missing from these studies, and this one is no different, is a lack of a description of what this actually means. Why would a person avoid pain and another confront it? The descriptions are usually left under the vague nature of "psychological issues."

One need only look toward Lorimer Moseley and Dr. Waddell for more. Dr. Moseley has shown us that beliefs about the nature of pain were discriminative in a group of people with experimentally induced pain of whose pain would continue. This adds to his research showing that educating the patient on pain physiology and thus giving them a more accurate understanding of pain, decreased their pain.

Waddell has shown that even the explanatory model of the clinician plays a role the persistence of pain.

Bottom line, change the belief about pain and you change the way a person behaves in response to pain. Change the behavior in response to pain and you can change the pain itself.

Friday, February 15, 2008

More Smartness II

In reference to Smart Prosthetics, Smart Nerves, Smart Brains
In reference to More Smartness:

This morning I happened to see this on Deric Bownd's Mindblog: A non-invasive brain-machine interface?

In it he blogs about a study that used magneto- and electro-encephalographic recordings only, to differentiate out signals for moving hands, with up to 67% accuracy. Here is the abstract of Hand Movement Direction Decoded from MEG and EEG by Waldert et al:
"Brain activity can be used as a control signal for brain–machine interfaces (BMIs). A powerful and widely acknowledged BMI approach, so far only applied in invasive recording techniques, uses neuronal signals related to limb movements for equivalent, multidimensional control of an external effector. Here, we investigated whether this approach is also applicable for noninvasive recording techniques. To this end, we recorded whole-head MEG during center-out movements with the hand and found significant power modulation of MEG activity between rest and movement in three frequency bands: an increase for 7 Hz (low-frequency band) and 62–87 Hz (high- band) and a decrease for 10–30 Hz (β band) during movement. Movement directions could be inferred on a single-trial basis from the low-pass filtered MEG activity as well as from power modulations in the low-frequency band, but not from the β and high- bands. Using sensors above the motor area, we obtained a surprisingly high decoding accuracy of 67% on average across subjects. Decoding accuracy started to rise significantly above chance level before movement onset. Based on simultaneous MEG and EEG recordings, we show that the inference of movement direction works equally well for both recording techniques. In summary, our results show that neuronal activity associated with different movements of the same effector can be distinguished by means of noninvasive recordings and might, thus, be used to drive a noninvasive BMI."

Brain-machine interface research looks to be a red-hot field of endeavor. Anything that doesn't involve having to plug actual wires into actual brains is likely to have a higher chance of catching on as a widespread innovation. I am truly amazed at this kind of work. I look forward to finding out how much easier life may become for those who have had spinal cord injuries, stroke etc., and for the caregivers of these people, including those in my own profession involved in neurorehabilitation.

This paper was from last year; the link does not appear to have citations listed. The Nicolelis monkey/treadmill research was conducted this year. Here are more papers on Brain-Machine interface, from the wikipedia link to Miguel Nicolelis:

Lebedev, M.A., Carmena, J.M., O’Doherty, J.E., Zacksenhouse, M., Henriquez, C.S., Principe, J.C., Nicolelis, M.A.L. (2005) Cortical ensemble adaptation to represent actuators controlled by a brain machine interface. J. Neurosci. 25: 4681-4693.

Santucci, D.M., Kralik, J.D., Lebedev , M.A., Nicolelis, M.A.L. (2005) Frontal and parietal cortical ensembles predict single-trial muscle activity during reaching movements. Eur. J. Neurosci., 22: 1529-1540.

Carmena, J.M., Lebedev, M.A., Crist, R.E., O’Doherty, J.E., Santucci, D.M., Dimitrov, D.F., Patil, P.G., Henriquez, C.S., Nicolelis, M.A.L. (2003) Learning to control a brain-machine interface for reaching and grasping by primates. PLoS Biology, 1: 193-208.

Nicolelis MA (2003) Brain-machine interfaces to restore motor function and probe neural circuits. Nat Rev Neurosci. 4: 417-422.

Wessberg J, Stambaugh CR, Kralik JD, Beck PD, Laubach M, Chapin JK, Kim J, Biggs SJ, Srinivasan MA, Nicolelis MA. (2000) Real-time prediction of hand trajectory by ensembles of cortical neurons in primates. Nature 16: 361-365.

Thursday, February 14, 2008

Hi Cory!

Response to: New Neurotonics Team Member

Hi Cory!

Welcome to the family. ;-)
Glad you agreed to join our blog.

As I've just announced on my blog I have to take a little break from contributing - my brain just doesn't let me write meaningful stuff at the moment.

And since I don't want to compromise quality I will just relax for a few weeks. I will however be reading everything you two write in the meantime! ;-)

Wednesday, February 13, 2008

Glad to be here

In reference to New Neurotonics Team Member:

Thanks Diane. I'm excited to be able to contribute and hope I am up to the standards of excellence that you and Matthias have established.

New Neurotonics Team Member

In reference to New PT Team Blog:

I'm pleased to announce that Cory Blickenstaff, a PT in the state of Washington, owner of a new, thriving solo PT practice and dad of a new baby boy, will be joining us here at Neurotonics presently, our third author. A link will be up soon.

Cory is a longtime member and moderator at SomaSimple, the one and only public neuroscientific PT discussion forum in existence so far, to my knowledge.

Welcome Cory. We look forward to conversing and posting with you here.

Sunday, February 10, 2008

More Smartness

In reference to Smart Prosthetics, Smart Nerves, Smart Brains:

From the wikipedia link on haptic technology, check out the virtual back that gives osteopathic students feedback on their handling. Hopefully it will help them learn to have lighter touch. I see the virtual back has no nerves associated with it. There is also a link to a site about a robotic hand which looks promising.

I found some more links that have to do with the bionic arm:

1. Here is Todd Kuiken, the surgeon who performed the nerve transplant.
2. Here is Claudia Mitchell, the girl with a new left arm.
3. Here is Jesse Sullivan, the man who had nerve transplantation, with Dr. Kuiken.
4. Here is more about Jesse Sullivan, and we are also introduced to the work of Miguel Nicolelis, a Brazilian researcher.
"Some of the most innovative research is being done by Miguel Nicolelis, a neurologist at Duke. He has bypassed the muscle system entirely. His experiments are based on directly reading the firing of neurons in the brains of monkeys. Neurosurgeons implanted an electrode with tiny wires into the surface of an animal's brain, and then connected them to a computer."

5. He was able to train a monkey to walk on a treadmill, put implants in her brain, which picked up her intent to walk, to send signals to a robot in Japan, which in turn walked on a treadmill. All in real time. Check it out. This is quite amazing to me.

Smart Prosthetics, Smart Nerves, Smart Brains

In reference to Learning (Dec 12/ 2007):

Matthias said:
If you look at a genius like Dean Kamen - a great inventor - you will see what I mean.
He is creative and simply doesn't give up.

I watched his 5 minute TED talk and was impressed.

Lately a reader, Kent, sent me this Nov 07 article from BBC news on a parallel development in the UK. It explains how a bionic arm can "feel" - it can't really; there is no way to literally hook a brain up to a device that can be put on and taken off, despite innovations in haptic technology (see here for an old post called Haptic Vest). In this case the amputees "learned" to "feel" their prosthetic arm through sensory nerve transplant from arm to chest wall. They learned to discriminate sensation of their chest skin from that of their "hand".

Fortunately the (very very cool!) original paper by Todd Kuiken et al. is open access. Take a look at the graphics depicting the amazing amount of sensory discrimination the two subjects were able to attain. They relearned their way out of numbness, essentially. The male subject had lost both upper limbs and the female subject had lost her left upper limb. It took awhile, but the sensory nerves to arm/hand transplanted into the chest skin eventually turned back on and their brains rewired for appropriate data collection. Interesting about subcutaneous fat being removed - this moved skin closer to muscle, stimulating the nerves more with underlying muscle movement.


Amputees cannot feel what they touch with their artificial hands, which severely limits usefulness of those hands. We have developed a technique that transfers remaining arm nerves to residual chest muscles after an amputation. This technique allows some sensory nerves from the amputated limb to reinnervate overlying chest skin. When this reinnervated skin is touched, the amputees perceive that they are being touched on their missing limb. We found that touch thresholds of the reinnervated chest skin fall within near-normal ranges, indicating the regeneration of large-fiber afferents. The perceptual identity of the limb and chest was maintained separately even though they shared a common skin surface. A cutaneous expression of proprioception also occurred in one reinnervated individual. Experiments with peltier temperature probes and surface electrical stimulation of the reinnervated skin indicate the regeneration of small diameter temperature and pain afferents. The perception of an amputated limb arising from stimulation of reinnervated chest skin may allow useful sensory feedback from prosthetic devices and provides insight into the mechanisms of neural plasticity and peripheral regeneration in humans.

This is yet another example of how profound neuroplasticity can be, quite apart from how capable the human brain is of incorporating objects into its brain maps (see Place Cells and Grid Cells Part I and Part II).

Wednesday, February 6, 2008

Stopping Disc Spin

Paul Mintken gathered together a lot of articles to support his statement that imaging of funny looking discs and pain do not correlate particularly well. You can read his post here.

A good post, but I have a wee issue with this first statement:
"I just don’t know if we are ever going to be able to isolate the pain generator in the majority of patients with low back pain."

Um, how about the nervous system Paul?