The importance of contextual exposure

Neil - Doctor of PhysiotherapyUncategorized0 Comments

This post comes off the back of my Facebook Live post here this morning: ‘Going full nerd’.

Classical or Pavlovian conditioning refers to a learning procedure of coupling a conditioned response to a previously neutral stimulus. It’s called associative learning; associating one thing with another. Pavlov famously conditioned a dog to start salivating at the sound of a bell ringing.

Bending forward is normally a neutral stimulus; we should be able to do it without anxiety, fear, pain or any other unwanted symptom which may adversely affect our ability to perform the task. Bending forward toward the ground to pick an object up from the floor is a fundamental human function.

Fear and pain are examples of an unconditioned stimulus; sometimes they just happen.

As with Pavlov’s dog, humans can be conditioned to associate activities, such as bending and lifting, with an unconditioned stimulus, like fear and pain.

When a Physiotherapist suggests that bending forward is the cause of harm to a disc, potentially dangerous (especially with twisting, because that’s *really* bad, right?), or likely to exacerbate symptoms attributed to a structure in the back, the act of bending forward can acquire the motivational properties of the unconditioned response – fear and pain. The very *thought* of bending forward can induce fear, anxiety and pain without even moving. Expectation is a powerful thing.

On the latest episode of the PT Matter Podcast (episode 39), Jack Chew shares with Paula Deacon a recent experience of hearing a Physiotherapist suggest that an intervertebral disc was less like the jam doughnut we so frequently hear of, and more like a vanilla slice, because that soft, squishy centre could squeeze out in any direction, not just along the path of least resistance where it went in. WTF! It’s no wonder that prominent Physios like Adam Meakins are making comments like this:

“Physio as a profession is at the bottom of the pile in most patient’s minds as being a skilled and knowledgeable profession.”

Sometimes the goal of Physiotherapy is to un-couple an unconditioned stimulus from its conditioned response; in this instance to make the thought and act of bending forward, an unconscious, asymptomatic (pain-free) behaviour.

‘Extinction’ is the act of reducing or (ideally) eliminating the conditioned response. Part of this process in what we do is having the individual repeatedly perform the behaviour in the absence of the conditioned stimulus (fear and pain).

‘Exposure Therapy’ can be used to treat, for example, a fear of spiders. Exposing oneself to spiders and grading the exposure to the stimulus over time can help reduce the fear. The size (money spider to tarantula), body location (crawling on hand or face) and duration can all be increased.

‘Extinction’ (reducing or eliminating unwanted symptom) doesn’t work the same way as simple exposure therapy. It’s a lot more complex than simply having someone feel less fearful. Anxiety for example, inhibits the processes believed to be responsible for extinction. Someone may remain fearful but feel no pain with bending forward. Nor is extinction simply a process of ‘un-coupling’ something in the brain. If extinction occurs, it is specific to a context or setting. Having someone bend forward and pick up a load in a clinic setting is not the same as doing the same thing in work or play, so exposure needs to be repeated often and in varied setting. This also needs to happen indefinitely because like memories, the conditioned response doesn’t simply stop or go away, even though it may be ‘extinct’ in terms of physical function.

The individual must understand that trauma, for example falling and hurting the same body part, can cause a rapid reacquisition of the conditioned response; it can easily come back.
One of our approaches as a Physiotherapist is to violate the expectation of the conditioned response. Here’s where it can get a little hairy though; the greater the violation of expectation (lifting 20kg off the floor would be a greater violation than lifting just 5kg), the better the effect. The cognitive mismatch is critical to the inhibitory learning process.

In a similar way to increasing someone’s tissue tolerance and physical capacity, such that everyday activities become increasingly easier relative to ‘max’, the same can be said of these cognitive process. If someone can pick up 40kg without fear or back pain, picking up a newspaper shouldn’t then be a valid cognitive trigger for either symptom. Inhibitory ‘learning’ is a cognitive process; it is not simply reducing fear through exposure-based habituation.

Clinically, it is important that we don’t discuss the how and why prior to an exposure event as that would likely diminish the violation. If I tell you that there’s going to be a loud bang, you’ll be less surprised by it than if you hadn’t been forewarned. In addition, to get the most out of the learning process, it is important that someone doesn’t just go through the motions, so to speak. As a ‘cognitive’ process, the individual needs to make sense of what’s happened. They need to actively process their thoughts and make sense of it, because disconfirmation is more effective than habituation.

The learning is consolidated by the individual articulating their experience and thoughts about what happened after the exposure event. The discrepancy between what is predicted and what actually occurred determines the degree of associative change. Linguistic processing or ‘affect labelling’ reduces activity in a part of the brain which helps to attenuate anxiety. Simply describing one’s emotional response to what happens through exposure and the inhibitory learning experience, appears to have a greater affect than trying to appraise and make sense of the situation, distraction, or the exposure alone.

Graded exposure is increasing the degree of violation. In our practice setting at PRIDE, bending forward to pick a load up off the floor can start from as little as 4kg, and increase to 48kg with a single kettlebell – it’s just a weight with a handle on it, but so is a handbag or shopping bag! The lady I mentioned in the FB Live post had a 3-tin weight limit per bag at the supermarket. She couldn’t easily put her shoes on or off and wouldn’t get down to the ground to lie down because she couldn’t get back up again; consider for a moment that level of disability and fear. That’s not a good way to be going through life.

This isn’t a one-time event. It needs to be repeated and performed in multiple contexts indefinitely. That doesn’t need to be with a Physiotherapist. Providing the individual receives the education, reassurance, guidance and correct intervention from the start, the locus of control should remain with them, with sufficient self-efficacy to be able to self-manage the process independently.

In addition, we should be promoting movement and physical activity as per the ‘movement for movement’ here. Physical activity is good for our health!

‘Why fitness actually matters’, by Mike Vacanti – “One of the main reasons people end up in assisted living is because they can’t get off a toilet; they can’t do a half rep of a single body weight squat to get off the toilet” here

This is the philosophy behind the work of Canadian Physiotherapist Christina Nowak at www.staveoff.ca, Dr Scotty Butcher (PhD) at Synergy Strength, and Dustin Jones who hosts the Senior Rehab podcast, who all work with older adults – strength training. It’s well publicised that older adults are significantly under-loaded and the kinesiophobic beliefs of a therapist influence what we have the client doing; if they’re old and fragile, they can’t possibly load them up, right? “You don’t have kinesiophobia but dammit I can give it to you!” J.W. Matheson said here and I posted the same here with a quote from Craig Liebenson “In rehab, we don’t use strengthening or loading to the best of our ability. We think our patients are more fragile than they actually are.”

So, what triggered all this was Dr Derek Griffin’s Tweet 3 days ago, about the importance of contextual exposure in cases of persistent (chronic) pain cases.

Loading is normal. Loading is healthy and a necessary part of being human. Loading increases tissue tolerance and helpful adaptation. Loading is functional and arguably helps protect from injury. Over-loading can cause pathological changes in tissues and structure. Pathological changes may act as a precursor to unwanted symptoms, and overload can be an accelerant to ignite a ‘fire’ of unwanted symptoms, in particular pain (see Greg Lehman’s post about this here – Greg was voted the best clinician in the world here, so what he says is quite frankly gospel). Loading can help modulate pain. Loading creates physical and psychological resilience (Erik Meira said that here, and he was voted No.2 so we’re not going to argue with him either).

However… with persistent pain, loading is managed differently, as Derek has pointed out.

Physiotherapy is as much art as it is science. Sometimes we can do a reasonable job with one and not the other, but in cases of persistent pain, getting an optimal outcome requires a good grasp of both the science (this stuff) and art (alliance and the 5 E’s).

As I said here this morning, if you want optimal care from a Physiotherapist, vote with your feet and don’t accept low value care from a Physiotherapist!!!!

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