They gone? Good. Now dim the lights… Turn on the Barry White and let’s get it on.

We’re going to talk about one of the sexiest topics in rehab. Learning, motor learning to be exact.

Wait, learning about learning isn’t sexy? It’s not EMG studies of the rotator cuff at differing shoulder positions, or open vs. closed chain kinematics of the knee joint, but without motor learning there would be no physical therapy, good strength and conditioning, or probably life for that matter.

After an injury, or leading up to an injury, there are typically compensations within the body. These compensations are learned by the body to allow tasks or skills to be performed, regardless of how they are performed. When re-training the body, motor patterns must be assessed, and when deficiencies are found, proper methods must be taught to retrain the body. The body must learn (or re-learn) how to properly move, and it does this through motor learning.

If you’re in Neuro-rehabiliation class, you’ll probably hear something like, “The acquisition of skills or skilled movements as a result of practice. Motor learning involves a set of internal processes associated with practice or experience leading to relatively permanent changes in motor skill [10],” as the definition of motor learning. The most important aspect of this learning process differs for everyone depending on their injury, the task, the environment, and the individual [4], but without PRACTICE, motor learning cannot occur.

The BASIC (very basic) physiological processes that occur with motor learning include creation of the idea of motion in the pre-motor cortex and basal ganglia (ideation) with transmission to the primary motor cortex for proper motor planning (organization). From here the signal travels to the spinal cord, then to the efferent nerves to tell the muscles to move (execution) [3]. From here, there is visual and tactile feedback leading to the cerebellum to either say, “yes that’s how it is done,” or “no, let’s try this a different way” (The amount that the cerebellum inputs decreases as the outcomes improve [6]). When a motion is not done correctly (wrong speed, accuracy, precision, etc), or the outcome is not as desired, the brain will attempt a different method to perform the skill; using a different neural pathway in the brain, like taking a detour to arrive at the same destination in the end.

There are really two types of learning that occur, just like short term and long term memory. There is fast learning, which usually occurs over one practice session, and slow learning, which occurs over many practice sessions [6],[7]. This slow learning is where the skill becomes “automatic” to perform.

If the motor pathways have been retained, the next time the “skill” is attempted it will be done correctly; however, many times, a person will be able to correctly perform a movement, but when asked to do so again during the next practice session they will not be able to. At this point, further practice, and differing environments must be attempted. Obviously, this is a very basic gist of what occurs during motor learning. Basically it is trial and error, until the brain can find the right “pathway” where the outcomes and performance are performed correctly. I say outcomes AND performance, because as we will see with practice, how the outcomes are achieved is as, if not more, important initially than the outcomes.

clearly i could use some motor learning for my hand writing

As stated earlier, motor learning is usually composed of three aspects; the task, the environment, and the individual.

Task: Tasks can be discrete, serial, or continuous [4], [9].

• Discrete – These tasks have a clear beginning, middle, and end, and do not continue into other tasks. An example of this would be moving a coffee mug to a target on a table.
• Serial – These are tasks composed of a series of discrete tasks such as moving that mug then standing up.
• Continuous – There is no discernible beginning, middle, or end to these tasks. The best example I can think of would be taking part in a certain sport like playing basketball, where there are many tasks taking place at the same time that have no clear-cut beginnings and ends.

Environment: This is an easy concept to grasp. They can be closed or open [5] .

• Closed – These environments are controlled. The more closed the environment, the more control of the practice the therapist has. An example would be walking up stairs in the clinic with supervision.
• Open – Obviously this is the complete opposite. If that same person is walking up the busy stairs of their work place with people coming past them up and down, the environment is less controlled.

The Individual: There are three stages of learning a skill that are internalized by the learner. These are the Cognitive, Associative, and Autonomous Phases. There are also other variables of the individual which will influence their learning such as age, injury, and preferred learning style [1],[2].

• Cognitive – This stage can last for only a couple of minutes, or it can last weeks depending on the other factors of learning discussed so far and to come. During this stage a person needs to literally think about every step of the skill or task. This stage includes many errors by the patient in velocity, accuracy, consistency, etc.
• Associative – During this stage, the person begins to make fewer errors while gaining an internal “sense” of what they need to do to perform the skill.
• Autonomous – This stage is also known as the automatic stage, because at this point, the skill becomes almost automatic. Think of Ray Allen shooting free-throws. 90% of the time he’s automatic. He has done this skill so many times that he can almost perform it without error. To some of us, the skill may be walking, and others, an RDL. Regardless of what they’re doing, a learner must get to this point before they can perform the skill without really “thinking” about it.

As we age, our brains have a more difficult time learning new skills [8] (motor and cognitive) . This is primarily because our neural pathways have been established for years, and our neurotransmitters are firing at differing rates than they used to! A perfect example of this would be learning to speak a new language. The 2 year-old raised by his bi-lingual nanny usually has no problem learning whatever other language his caretaker speaks, while the 40-year-old father who has the nanny as his mistress will have much difficulty learning her language. This difficulty with learning a language translates to motor learning as well. Also, as we age our neural firing rates decrease, making adjustments based on feedback a little tougher, resulting in less accuracy, and worse outcomes/learning.

People’s injuries also play a huge roll in motor learning. Whether or not the injury is of neural nature, or if proprioception has been disturbed, will all lead to differences in motor learning and rehabilitation. If you take one joint and compare three different injuries, you will see how learning the same skill can vary. If you compare a stroke, versus an ankle ligament reconstruction, versus a stage 2 ATFL sprain there will be significant differences in the amount of practice, duration of the stages of learning, and ease at which an open environment is introduced when (re-)learning single leg stance.

Although I focussed  on rehabilitation and learning, these same principles apply to strength and conditioning. People will have their pre-programmed movement patterns already, which can lead to undesirable motions or exercise performance. This can either lead to future injury, or an inability to progress. All the above factors must be taken into consideration when teaching a client a new exercise or concept. Someone must exhibit automatic performance of a skill prior to being able to progress to a higher level or more weights. It is always my suggestion that lower weights (like ridiculously low) be used initially to teach any exercise/movement, whether in the rehab setting or strength and conditioning setting.

Stay tuned for the future discussion on practice, but until then, always evolve.

-Mike

P.S. – You can put your pants back on now

Resources:

1. Fitts, P.M., & Posner, M.I. (1967). Learning and skilled performance in human performance. Belmont CA: Brock-Cole.

2. Gentile, A. (2000). Skill acquisition: Action, movement, and neuromotor processes. In: Carr, J., & Shepherd, R. Movement science: Foundations for physical therapy in rehabilitation . (2nd ed.). Gaithersburg, MD: Aspen.

3. http://67.80.203.99:98/spectrumcenter.net/dyspraxia.html

4. http://moon.ouhsc.edu/dthompso/mtrlrng/mtrlrng.htm

5. http://moon.ouhsc.edu/dthompso/mtrlrng/tasktype.htm

6. Karni, A, et al. Functional MRI evidence for adult motor cortex plasticity during motor skill learning. Nature. 1995 Sep 14;377(6545):155-8.

7. LG Ungerleider, J Doyon, A Karni. Imaging Brain Plasticity during Motor Skill Learning.  Neurobiology of Learning and Memory, 2002.

8. McNay, E.C., Willingham, D.B. Deficit in learning of a motor skill requiring strategy, but not of perceptuomotor recalibration, with aging. Learn. Mem. 1998. 4:411–420

9. Schmidt, R.A. (1988). Motor learning and control: A behavioral emphasis. (2nd ed.). Champaign, IL: Human Kinetics.

10. www.Answers.com – Definition of “motor learning”. 10/6/2010.