• In our first blog post, you learned about the importance of exercise, both for the body and for the brain.  You also learned about neuroprotection which is the slowing, stopping, or reversing of a neurodegenerative process with exercise.  In this second blog, you will learn about the concept of neuroplasticity and how the brain can be altered by doing…and not doing.  Please remember when reading this series to keep your own personal medical history in mind and consult with your physical therapist or physician before beginning or changing your exercise program.

    What is neuroplasticity?

    Neuroplasticity is the process of brain repair and reorganization by which your brain can create new or strengthen old connections in the brain.  In other words, neuroplasticity is the way the brain adapts and the way neuron structure and function is altered.  This process happens through practice of a behavior or skill – physical therapists often refer to this as “task practice.”  There are several rules that govern this process that we will discuss below.

    What is a task or skill?

    Have you ever been told to walk bigger or talk louder?  Or maybe you’ve been told to stand up taller?  Moving big, standing tall, and talking loud are important tasks that people with Parkinson’s Disease need to work on.  Other examples of tasks or skills include getting up out of your favorite squishy chair, improving your tennis backhand, and buttoning those pesky shirtsleeve buttons (seriously, can they make them any smaller?).  Almost anything you do during your day can be considered a task.  You can learn to do a task better and maintain that improved function – a neuroplastic change in the brain – by following several rules.

    What are the neuroplastic principles?

    Kleim and Jones (2008) do a great job of describing what is involved in making a brain change to alter a person’s ability to perform a task.  The first rule you have likely heard before – Use It or Lose It! If you do not use an area of the brain, it will be used for something else.  For example, in some people who are deaf, the hearing portion of the brain will light up to visual stimuli because it is not being used for auditory stimuli.  Use it or lose it also applies to function – if you don’t do an action over time, your performance of that function will worsen.  For example, researchers have found that tube feeding leads to disuse of the swallowing brain circuits which in turn may lead to further loss of swallowing function.

    But it’s not just enough to use it…you have to use it and improve it!  Performance improves more if you train harder.  You can do this through manipulating the concepts of repetition and intensity.  Repetition, or doing a task over and over again, is required to induce a lasting neural change.  Research shows that it takes thousands of repetitions over time to make a brain change.  That’s a lot of big steps and shirt buttons!  Also, if a skill is not repeated often enough your brain pathways will decay and your skill performance will get worse (which circles back to the use it or lose it concept).  For example, if you haven’t picked up a golf club in a few years and then you suddenly decide to play a round, your score will most likely be worse than it was the last time you played.

    Intensity relates to the amount of challenge you are putting on yourself when practicing a task.  This concept is related to both repetition and use it or lose it.  To increase the intensity of a task, a physical therapist will often manipulate variables of the task to make it harder.  For example, they may have you hold weights while you are practicing getting up from a low chair or they may make you perform 20 repetitions in a row instead of 10.

    Specific practice is also important to creating a neuroplastic change in the brain.  As Kleim eloquently stated, “Learning or skill acquisition, rather than mere use, seem to be required to produce significant changes in patterns of neural connectivity.”  For example, practicing walking will not improve your ability to take big steps but practicing walking with big steps will. Another way to think about this is skilled vs. unskilled practice.  In a study by Perez in 2004, participants were divided into two groups with both groups practicing ankle movements.  The first group was required to make a cursor attached to their foot follow a series of target lines on a computer by moving their ankle.  The second group had to simply move their ankle in specified directions with and without assistance.  Perez found that the first group, who had to acquire a skill, had enhanced brain excitability and the second group that simply moved their foot around did not make cortical changes.

    It is also important to realize that there are things that can get in the way of the neuroplastic process and motor learning.  We call this interference.  For example, if you only practice performing a task the right way during your physical therapy session and then spend the rest of the day performing it incorrectly, you have just interfered with the motor learning you gained during your PT session.  Also, different types and delivery of feedback about the quality of a task can actually interfere with motor movements.  For example, sometimes if a physical therapist or family member gives too many cues to a person, this can actually get in the way of motor learning.  This is why it is important to work with a physical therapist who understands neuroplasticity and motor learning so that they can teach you and your family how to minimize interference.

    So how do you turn a task into an exercise?

    By following some of the neuroplastic principles above, such as repetition and intensity, you can turn any task into an exercise.  Try standing up and sitting down from your low couch 10 or more times in a row or walking with very big steps for 10 minutes to see what I mean.  Physical therapists are great at turning everyday tasks into exercises that can make you stronger, improve your endurance, and improve your ability to perform that task through neuroplasticity.  I recommend you consult with your physical therapist for personalized suggestions on a task based exercise program.  (Stay tuned for Part 4 to learn how a physical therapist can help people with PD move better through exercise and tips on how to find a neurologic physical therapist.)

    You have now learned about the benefits of exercise, the concepts of neuroprotection and neuroplasticity, and the importance of task practice.  Please join me next time for Part 3 which will discuss different types of exercise and our national exercise guidelines.

    Move BIG and use it or lose it!

    All the best,

    Theresa

    References:
    Adkins et al. Motor training induces experience specific patterns of plasticity across motor cortex and spinal cord. journal of applied physiology. 101(6):1776-1782, 2006.
    Boyd L, Winstein C, Explicit information interferes with implicit motor learning of both continuous and discrete movement tasks after stroke. Journal of neuralgic physical therapy. 30(2):46-57, 2006.
    Hirsch MA, Farley BG.  Exercise and neuroplasticity in persons living with Parkinson’s Disease. Eru J Phys Rehabil Med.  2009;45(2):215-29.
    Garber CE et al.  Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in aparently healthy adults: guidance for prescribing exercise.  Medicine and Science in Sports and Exercise.  43(7):1334-1359. 2011.
    Kleim JA, Jones TA.  Principles of experience-dependent neural plasticity: Implications for rehabilitation after brain damage.  Journal of Speech, Language, and Hearing Research.  S225-S239.  2008
    Lang CE et al. counting repetitions; an observational study of out-pt PT for people with hemiparesis post stroke. Journal of nerologic physical therapy. 31:1-10, 2007.
    Monfils MH et al. In search of the motor engram: motor map plasticity as a mechanism of encoding motor experience. Neuroscientist 11(5):471-483, 2005.
    “Neuroprotective Benefits of Exercise.” National Parkinson Foundation.  Accessed at: http://www.parkinson.org/Parkinson-s-Disease/Treatment/Exercise/Neuroprotective-Benefits-of-Exercise  Accessed on: 4/20/2014.
    Perez MA et al.  Motor skill training induces changes in the excitability of the leg cortical area in healthy humans.  Experimental Brain Research.159: 197-205, 2004.
    “Physical Activity.”  Centers for Disease Control and Prevention.  Accessed at:  http://www.cdc.gov/physicalactivity/  Accessed on: 4/15/2014
    Winstein, CJ et al. A randomized controlled comparison of UE rehab strategies in acute stroke: a pilot study of immediate and long term outcomes. Arches of PM&R 85(4):620-628, 2004.
    Widner, G.  Lecture.  “Neuroprotection and neuroplasticity as a basis for rehabilitation.”  March 27, 2010.
    Wolf SL et al. Effect of constraint-induced therapy on UE function 3 and 9 months after stroke. Journal of the american medical association. 296(17):2095-2104, 2006.