Searching for Rene?

We stumbled across this video on YouTube. It has some terrific graphics and is well worth a look. It also has a spectacularly deep voiced star-trek type talking us through some of the neurochemical processes that occur when tissue is injured or inflamed. It touches on descending modulation, although attributes that to only one brainstem nucleus, and it does not touch on brain processing in any detailed way.  It gets onto substance P and CGRP.

Some of you might recall a quasi game called Searching for Rene, which forces us to carefully monitor what we are saying to people in pain, because they are often searching for any piece of evidence in what we say or how we say it that would support a Rene Descartes-like understanding of pain. Well as flash as this video is, it still commits some faux pas in this way. We found Rene. Can you?

Comments

  1. Type 3 and 4 muscle fibers – what are they?
    Stew Wild

  2. Frédéric Wellens,pht says:

    nociceptive pain originates in the tissues only to be perceived by the brain. That sounds cartesianly Rene to me!

  3. Jerry Draper-Rodi says:

    Is it one of the Rene?
    “The signal is then relate via ascending nociceptor pathways to higher centres in the brain where it is perceived as pain”

  4. Vegard Ølstørn says:

    Is it the last sentence which points back to nociceptive signals but they term it pain?

  5. ‘Nociceptive pain originates in the nociceptors’ – isn’t this line labelled and ignoring that the reign of pain lies mainly in the brain or is an emergent property ? Can someone please clear something up for me. I still have trouble understanding why the gate control theory is still used even now (by some Professors, Pain presenters, and more) as an ascending system in which large fibre afferents ‘block’ small (unmyelinated or myelinated) nociceptive afferents. The modulation part (unless I am confused) happens for the most part centrally and is top down (and obviously not just from one area). Facilitation does not only happen as a result of protection against tissue damage – it happens because of perception/context of danger to the person (with resultant output) just like inhibition (Lorimer’s snakebite bit and the boring talker is really helpful). Is the dorsal horn really the only playing field for facilitation and inhibition ? Is the dorsal horn really the only gate to the house of pain or are there many gates (centrally) to awareness ? Really appreciated the cool special effects. Would appreciate help in better understanding of a very complex system. Please help correct some of my misperceptions.

  6. Lorimer Moseley says:

    Smashing work folks – i think there is one more……

  7. Maree Jones says:

    Rene would of loved this video! He would feel vindicated by modern science. Leaving aside the science though and looking at it from a lay perspective (our patients are generally not scientists or therapists) I felt that the last sentence was worrying. ” Inhibition may serve to provide analgesia at times of danger so that pain may not compromise function”. This statement may well have some truth in it but it leaves the reader with the idea that pain indicates danger and compromises function. It divorces pain from the self and encourages the idea that pain means tissue damage indicates danger. Great presentation though.

  8. Maree Jones says:

    Oops excuse the typo above. There should be an ‘and’ between ’tissue damage’ and ‘indicates danger’

  9. Hey Lorimer,
    What should I say to the young physical therapists who are still taught that by grading their manual therapy that they are somehow directly blocking the ‘gate’of afferent input from nociceptors centrally? I get a bit lost when talking about what happens in different modes of transmission in the dorsal horn (suppressed, facilitated and structurally reorganized) especially when you are also trying to understand synaptic transmission of different transmitters (pre-synaptic and post-synaptic effects). I am ok with substance P and NK1 receptors and leaving it at that. It’s enough to have ‘Explain Pain’ or a simple video when dealing with a patient with severe pain and trying to provide education to patient as well as student. I usually just get them to read one of your articles (the student not the patient) but this video could be used (I guess) as a teaching tool even with some challenges. Again, is it critically important to understand what happens at the dorsal horn to explain concepts of hyperalgesia (primary and secondary) and allodynia to patients ? Is there AB-fibre sprouting into lamina 1/2 with interneuron degeneration as Woolf and others propose with persistent allodynia (or should it be explained via descending facilitation with structural reorganization at higher level and/or both)? Luckily this video just talks of the brain in terms of perception without too many details and a little about descending input. It would be nice to hear from the spinal neuromodulation group about their beliefs on treating CRPS with spinal cord stimulators. I appreciate the comments from Maree about not linking pain with tissue damage. I still appreciate the reconceptualization of pain as a conscious correlate of the implicit perception that tissue is in danger. After that, the more I read, the more I consider and struggle to understand and wait for clarity. Any help ?

  10. Erik Ouellet says:

    Just the fact that that throughout the whole presentation, you can replace the term “nociception” or “nociceptors” with “pain” just doesn’t sound right. The two are just not the same and seem to get conflated at different moments in the video. Also, when the nociceptive signal reaches the brain, it doesn’t get perceived as pain, it’s the brain that decides if the nociceptive signal deserves to be addressed with a pain output. Is there even such a thing as a “nociceptor axon” ? It just sounds like Rene replaced pain with nociception just so he doesn’t feel left out.

  11. I would like to play this Searching for Rene game… where do I find it?

    Heidi Allen Reply:

    Hi Michael. Searching for Rene refers to an older blog post – I’ve put the link in there now so you can find it

  12. Hi everyone,

    I appreciate reading all of your above perspectives. May I just add my own take on this video…if pain was that simple I would think that pharmacology would have found a cure, and we know that NNT of neuropathic pain drugs are poor, so I am fearful of this explanation to patients and to myself. I think we need to go broader not narrower and remember that nociception is an alarm system and it is how the brain decides to interpret this is key, and multifactorial- sometimes justified and sometimes a little too efficient. i feel we need to take care of translating our nerdy passions with patients and discuss in language that is meaningful to them and relevant to their subjective experience of pain. The absence in this video of alternate cortical pathways concerns me. I much prefer the understanding pain clip in 5 mins, and of course using particular pages of your awesome book! Cheers, Rach