I recently attended another great course through the NOI Group called “Graded Motor Imagery” (GMI) taught by Bob Johnson. These guys are the industry leaders in all things pain so please check them out. It was great connecting with Bob and learning what I think will be an excellent adjunct to what I am currently doing. So here is the run down on GMI.
Table of Contents
GMI is a three-pronged sequential process of establishing early, nonpainful motor programming. Johnson calls this synaptic exercise to limit negative peripheral pain expression. GMI is a 3 step process:
1) Laterality reconstruction (Implicit Motor Imagery).
2) Motor imagery (Explicit Motor Imagery).
3) Mirror Therapy.
The Neuromatrix Paradigm & Pain States
Before delving into the neuromatrix, we first must define pain. Pain is a multiple system output or expression by an individual-specific pain neuromatrix that activates when the brain concludes that body tissues are in danger and action is required.
The neuromatrix, like I talk about in this post here, is the nervous system’s coding space and network. It is first and foremost affected by genetics, sculpted by experience, and constantly evolving. It is the entity that makes us who we are—the self.
The neurosignature, or neurotag, is an output’s representation in the brain. For example, regions in the brain will activate in response to produce the pain output. This sequence is the neurosignature. Some common activated areas when pain is expressed include both primary and secondary somatosensory cortices, insula cortex, anterior cingulgate cortex, thalamus, basal ganglia, and the cerebellum. However, areas activated differ among individuals.
A way to akin the neurotag is that of several movies occurring throughout the brain that represent past, present, and future. The United Airlines map is another example.
Neurotags have an activation threshold which can be modified by various ways. Some examples are the context of injury, beliefs, perceptions, feelings, and sensory input. Previous injury can also activate this neurotag and increase nervous system sensitivity.
If pain persists because the brain perceives the body as threatened, the pain neurotag becomes sensitized and disinhibited. These changes result in smaller inputs creating painful outputs and pain locations spreading.
There are several of these representations in the brain—motor, endocrine, immune, limbic, etc—but most famous is the somatosensory homunculus.
There are several key features of this homunculus
- Somatotopically organized – meaning different body parts are represented next to one another.
- Areas that require more sensation are larger, such as the hands
- These representations are dynamic throughout the day.
- They can be fooled.
What can be problematic is that in certain pain states smudging can occur, in which the representation is not seen as well in the brain. This change occurs in both acute and chronic pain states, though the brain activity is different. Areas can also become smudged depending on which parts a person may use more. The hand representation of a musician will likely be larger than a non-musician. It can also take on nonorganic parts, such as a wedding ring or a watch.
Graded Exposure & the Pain Neurotag
Graded exposure is a way to expose the brain to painful activity without activating the pain systems. This tactic can be performed by breaking down movements or changing the movement context.
To begin graded exposure, the patient’s baseline for each task must be found first. The baseline is the amount of activity that one can do without flaring up. A flare-up is when a certain amount of activity is performed that maintains the pain neurotag sensitization with the corresponding activity. This is a line we would ideally like to avoid, but is not something to freak out about if we hit.
There are three strategies in which people approach graded exposure.
- Fear-Aviodance (bad): Do less and less and not move toward the baseline.
- Boom-bust (bad): Ignore flare line and push through the pain barrier.
- Graded Exposure (good): Knock on the door where pain resides and slowly push farther and farther. Do not do too much or too little.
In order to perform graded exposure, the first step is to identify both physical and contextual fear-related challenges based on the painful movements. Physical challenges include performing the activity through a larger range of motion or for a longer duration. The activity can also be broken down into parts. Contextually, the activity can be changed several different ways.
- Threat and threatening equipment.
- Changing vision.
- Changing emotion.
- Changing meaning (kicking a ball instead of a straight leg raise).
- Non-contaminated representations.
- Change neighboring tissues.
But what if you try all of these ways and still get a pain response? Use your imagination…Literally. This is where GMI comes in, as it has the ability to fly under the radar of the pain neurotag yet still activate motor receptors.
If utilizing GMI, the above order must be performed, as research has shown that if you perform mirror therapy after laterality retraining there are negative benefits.
Implicit Motor Imagery (IMI)
IMI, or laterality retraining, is the ability to determine whether a presented image is left or right. Performing IMI disengages the primary motor cortex while simultaneously activating premotor cells. This activity may lead to decreased pain neurotag activity while still activating motor areas.
Left/right discrimination appears to be delayed in acute, expected, and chronic pain states. Some of the below conditions are affected per research.
- Complex regional pain syndrome (CRPS).
- Spatial neglect.
- Back pain.
- Neck pain.
- Knee pain.
- Carpal tunnel syndrome.
- Cervical dystonia.
- Focal dystonia.
- Congenitally absent hand.
Here are some normative values for IMI, though Bob suggested that normal will be very much patient-specific.
- Accuracy of 80% or above.
- Speed of 1.6 ± 0.5 s for necks and back. 2 ± 0.5 s for hands and feet.
- Accuracy and response time should be fairly symmetrical.
- Patient results should be stable for at least one week; should not fade out with stress.
- Personal relevance of responses should take precedence.
Other rules of thumb, typically reaction time increases with age, males are faster than females, and left handed people are faster than right handed (score).
Here are some potential indicators that would indicate a possible trial of using IMI.
- Ongoing pain.
- Some less obvious pain states.
- Variable diagnoses.
- Cold sensitivity.
- Tender away from injured site.
- Bilateral pain.
- Unpredictable treatment responses.
- Chasing pain.
- Everything hurts.
- Immune imbalances.
- Disembodiment metaphors.
- Two-point discrimination changes.
There are several ways to train IMI. The use of flashcards in various positions, finding body parts in magazines, digital cameras, basically any activity which challenges left and right discrimination is useful. The challenge of the pictures can also be increased depending on orientation.
You can also change the context of the pictures to further increase difficulty.
- Image number
- Image context (hand on plain background versus hand in patterned background).
- Different/abstract body parts (Painted or animal hand).
- With distraction.
If performing laterality retraining of the affected body region is painful, then adjacent or distal areas
The most important thing when training IMI is that accuracy is emphasized before speed and that the activity is relatively pain-free.
Explicit Motor Imagery (EMI)
EMI is imagining moving your own body without actually moving it. This activity leads to movement neurotags, namely the preparatory and initiating ones, to activate.
Intention → preparation→ carrying out→ evaluating
Observed, imagined, and performed movements activate many of the same brain regions albeit to varying degrees. Working from observation all the way to performance is essentially graded exposure from a top-down approach.
Research has actually demonstrated that imagining movement has been shown to increase pain and swelling in patients with CRPS type I. Therefore, sometimes this activity can be too much for patients. If you activate the pain neurotag, you may have to take a step back. Even if IMI is too much, then watching someone move is likely the most ideal.
To perform EMI, it is very important to imagine all movements in the first person. Imagining in first person makes the activity more kinesthetic than visual. It is very important to make the task individualized to facilitate best outcomes. Here are some ways to make EMI more effective.
- Have the eyes open/closed
- Imagine the affected body part in the starting position.
- Describe the environment.
- Demonstrate the movement.
- Use words to describe the process.
- Use cues from the 5 senses.
- Recall memories.
- Prior relaxation techniques.
- The activity should be imagined as long as it takes to do in reality.
Typically, here is the EMI progression that can be utilized.
Watch the activity –> Hold affected body part in static position –> dynamic imagery –> manipulate an object.
Mirror therapy is a novel way to trick the brain into thinking the moving limb is the hidden limb. When the limb is viewed in a mirror, the motor cortices in both brain areas are activated. This activation is more than in EMI, but less than actual movement. Mirror therapy is another step in graded exposure.
Sometimes with mirror therapy dysynchiria may occur, which is when the person feels pain or pins and needles in their hidden limb. This phenomenon most often occurs in patients with CRPS. If this does occur, it is important to advocate to the patient that nothing is being damaged because the hand is not even moving.
Here are some general guidelines to utilizing mirror therapy.
- No jewelry or cover tattoos on the affected side.
- The more severe the problem, the less movement amplitude and increased frequency may be needed.
- The patient cannot see the other side.
- Feel comfortable with the movement before progressing to a more challenging movement.
- Once you feel comfortable with a movement, change the context.
Here is a way to progress/regress mirror therapy.
|Threat value||Hand inside box||Hand outside box|
|Less threatening||Hand resting.||Hand resting. Just observe.|
|Hand resting.||Rotate the hand.|
|Hand resting.||Finger opposition.|
|Hand resting with a slight bend in the fingers.||Slow fists.|
|More threatening||Bend the wrist up/down within pain limits.||Bend the wrist up/down through full mobility.|
|Finger opposition gently touching together.||Forceful finger opposition.|
|Make a fist into some discomfort in time with outside hand.||Fist for repetitions.|
|Full mobility.||Copy hand in box.|
|Most threatening||Tool manipulation.||Copy hand in box.|
The Clinical Reality
Before GMI is implemented, the patient must first be educated on pain. Educating patients on pain physiology has been shown to have many benefits including decreased pain thresholds, improved pain beliefs and attitudes, and improving outcomes of therapeutic approaches.
The big keys that must be advocated include that the brain changes undergone with pain experiences do not equal brain damage. The nervous system is just unhealthy. These effects are reversible and take time. It is similar to learning to play a musical instrument. Jimmy Page didn’t become a great guitarist practicing two times a week for 4 weeks.
Many times patients may get the feeling that you are suggesting the pain is in the head which is not the case. However, the brain decides whether or not you will experience pain. A good example is an ankle sprain. Say you sprain your ankle on the street when all the sudden you notice a bus coming your way. Does the ankle sprain hurt at that moment? Not likely because your brain is going to be focused on you moving out of the bus’ way. Changing the patient’s mindset is key to having the most successful outcome.
Great Bob Johnson Quotes
- “The goal is pain freedom. Even if it hurts, I am less threatened.”
- “Ask with every patient how the nervous system is involved.”
- “If you say the neurodynamic tests involves only the median nerve you are lost.”
- “50% of people have joint noises. It is just the way your body protects you.”
- “The [nervous] system will do what it needs to survive.”
- “Get the patient to think they can get better and they will get better.”
- “One cannot have pain with just physical damage.”
- “Pain holds on because the patient is misunderstood, not broken.”
- “Just because the police are at the scene doesn’t mean they committed the crime.”
- “The motor homunculus doesn’t think muscles, it thinks movements.”
- “Glia are immune cells for the CNS. They are gates that turn the system on and off.
- “Movement is an antigen.”
- “Ask patients how stressed they were when they hurt themselves.”
- “Our goal is to get the patient moving without turning on the system.”
- “The two biggest factors for chronic pain development are work and home satisfaction.”
- “Two point discrimination treatment changes brain sensitivity and cortical reorganization.”
- “Emotion is lotion.”
- “I don’t take medical histories; I need to find out who the patient is.”
- “Imagining impossible movements are possible with phantom limbs.”
- “25% of premotor neurons are mirror neurons” This is why watching movement works.
Overall, I thought this was a fantastic course, and put more skills into my clinical skillset. It may take some time for me to implement GMI into my practice (I need to make a lot of laterality cards), but I bet this will be very useful.
I also wonder if there are potential for using this modality in a performance aspect. Imagery has been used with great outcomes in athletes, but laterality retraining and mirror boxes have not. Could this be another way to increase performance? Only time will tell.
To sign up for more NOI courses, check out www.noigroup.com