A stroke occurs when there is a disruption of blood flow to the brain which starves the brain tissue of oxygen and nutrients, and causes that part of the brain to die. A disruption can be caused by either a rupture of the blood vessel (an aneurism) or a blockage within the vessel. The larger the blood vessel that is involved, the larger the area of the brain that is affected. Strokes cause speech impediments, paralysis, unconsciousness and even death. Because the left side of the brain controls the right side of the body and vice versa, dysfunction as a result of a stroke occurs on the opposite side of the body. A heart attack is essentially the same thing, but the blood vessel that is blocked is in the heart, causing a part of the heart to die.
Before the discovery and understanding of the implications of neuroplasticity, the belief was that recovery from a major stroke or other brain lesion would only be minimal, since it was believed that certain parts of the brain controlled certain functions, and once a control centre for a particular function was disabled, nothing much could be done about it. Now we know that the brain is capable of reorganizing itself to such a great extent that remarkable recovery of movement as well as speech function is possible with the right therapy.
Edward Taub, a behavioural neuroscientist pioneered a method of stroke rehabilitation called “Constraint Induced Movement Therapy”, and thousands of stroke patients have recovered function to the point of being able to care for themselves and continue their careers.
Taub believes that part of the problem post stroke is learned; the patient quickly learns to stop using the limb which has lost function and relies instead on the “good” limb to do everything. If the brain is not challenged to try to use the affected limb, it will not change in order to learn to use it again. So Constraint-Induced Therapy involves immobilizing the “good” limb by using large, stiff mittens and slings so the patient is forced to use the limb affected by the stroke.
People go into therapy for two intensive weeks, and they are given simple tasks that mimic life activities starting with large motor movements, and with success moving gradually to fine motor skills. A patient may come into therapy with some ability to move an arm and extend a hand, and leave with the ability to do up buttons on a shirt. Absolutely astounding progress in just two weeks! Even people that had strokes many years ago can benefit from this kind of
Patients wear their mitts and slings on their unaffected limbs 90% of the day while in therapy, and may start with exercises like wiping pots (the pot constrains the hand initially and helps teach the circular movement), wiping a table, putting large pegs into peg boards, picking up large balls, and later they put pennies into piggy banks for example. They learn to use a fork to pick up food and bring it to their mouths. Eventually skills are timed, so patients learn to be accurate and fast. By doing intensive work over two weeks, they get mass practice with incremental increases in difficulty which causes enormous brain (cortical) reorganization or plastic change. Function may not be quite what it was before the stroke, as neurons that are learning to take over a task may not be as effective as the ones that they are replacing, but all the same, it is possible to regain function to the point of giving someone back their life.
About 40% of those that have a left hemisphere stroke have damage to Broca’s area and therefore have speech deficits. How does one put a mitten on a tongue and jaw to help those who have lost speech function? Language rules are implemented into card games. As language skills improve, the rules become more stringent. The game is something like "Go Fish" with pictures of objects on them, where each in turn asks for the card they are seeking from a particular person. They would request the card with the rock on it, for example. Initially the only rule is they cannot use hand signals but must verbally request the card somehow. If they can't think of the name of the object they want, they can describe it instead. Once they have the pair they can discard it, and the person that gets rid of all their cards first wins.
More advanced versions of the game involve precisely naming the object they are looking for, or cards including colours and numbers so more
description is required. The participants that obeyed the rules of the game 3 hours a day for 10 consecutive days had a 30% improvement in
communication compared to the control group which got conventional therapy that involved repeating words.
This therapy works best if it is done all at once – mass practice over 2 weeks – rather than less frequent therapy over a longer duration. It seems the brain needs to be deprived of the alternatives in order to be forced to rewire itself.
This kind of therapy is useful not only for strokes, but also for those with movement and speech problems caused by cerebral palsy, spinal cord injuries, brain tumours, Parkinson's, and multiple sclerosis.
I think the concept of forcing the brain to learn to move the body differently would be useful in physiotherapy and exercise rehabilitation as
well, since poor movement patterns lead to joint problems and pain. By finding a way to completely block the unwanted movement pattern and forcing the brain to use a better movement strategy, perhaps we can more quickly and more effectively break bad habits, rehabilitate injuries and possibly prevent some from occurring in the first place. I have figured out a way to block a quadricep strategy in a lunge pattern, but still need to work out how to block other poor movement strategies and force good ones in other movement patterns like the squat, bend, upward scapular rotation and gait.
The information in this post is from the fabulous book by Norman Doidge, M.D. entitled The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science. I absolutely loved this book, as it provides so much hope for those suffering from a huge variety of problems ranging from depression and cognitive issues to balance problems, to sight impairments to motor control impairments. One learns about the scientists at the forefront of neuroplasticity research, and the patients they have helped.
If you want to subscribe or search for other posts by title or by topic, go to www.wellnesstips.ca.
Gauthier LV et al. Improvement After Constraint-Induced Movement Therapy Is Independent of Infarct Location in Chronic Stroke Patients Stroke. 2009;40:2468.
Smania N et al. A modified constraint-induced movement therapy (CIT) program improves paretic arm use and function in children with cerebral palsy (Europa Medicophysica) 2009 December;45(4):493-500
Morris DM et al. A method for standardizing procedures in rehabilitation: use in the extremity constraint induced therapy evaluation multisite randomized controlled trial. Arch Phys Med Rehabil. 2009 Apr;90(4):663-8.
Mark VW et al. Constraint-Induced Movement therapy can improve hemiparetic progressive multiple sclerosis. Preliminary findings. Mult Scler. 2008 Aug;14(7):992-4. Epub 2008 Jun 23.
Mark VW et al. MRI infarction load and CI therapy outcomes for chronic post-stroke hemiparesis. Restor Neurol Neurosci. 2008;26(1):13-33.
Gauthier LV et al. Remodeling the Brain: Plastic Structural Brain Changes Produced by Different Motor Therapies After Stroke (Stroke. 2008;39:1520.)
Wolf SL et al. Retention of upper limb function in stroke survivors who have received constraint-induced movement therapy: the EXCITE randomised trial. Lancet Neurol. 2008 Jan;7(1):33-40.
Mark VW et al. Poststroke cerebral peduncular atrophy correlates with a measure of corticospinal tract injury in the cerebral hemisphere. AJNR Am J Neuroradiol. 2008 Feb;29(2):354-8. Epub 2007 Nov 16.
Meinzer M et al. Extending the Constraint-Induced Movement Therapy (CIMT) approach to cognitive functions: Constraint-Induced Aphasia Therapy (CIAT) of chronic aphasia. NeuroRehabilitation. 2007;22(4):311-8.
Taub E et al. Pediatric CI therapy for stroke-induced hemiparesis in young children. Dev Neurorehabil. 2007 Jan-Mar;10(1):3-18.
Boake C et al. Constraint-induced movement therapy during early stroke rehabilitation. Neurorehabil Neural Repair. 2007 Jan-Feb;21(1):14-24.
Wolf SL et al. Effect of constraint-induced movement therapy on upper extremity function 3 to 9 months after stroke: the EXCITE randomized clinical trial. JAMA. 2006 Nov 1;296(17):2095-104.
Lum PS et al. A telerehabilitation approach to delivery of constraint-induced movement therapy. J Rehabil Res Dev. 2006 May-Jun;43(3):391-400.
Mark VW et al. Neuroplasticity and constraint-induced movement therapy.Eura Medicophys. 2006 Sep;42(3):269-84.
Morris DM, et al. Constraint-induced movement therapy: characterizing the intervention protocol. Eura Medicophys. 2006 Sep;42(3):257-68.
Taub E et al. The learned nonuse phenomenon: implications for rehabilitation. Eura Medicophys. 2006 Sep;42(3):241-56.
Taub, E. et al.(2006). A placebo controlled trial of Constraint-Induced Movement therapy for upper extremity after stroke. Stroke, 37, 1045-1049.
Copyright 2010 Vreni Gurd
To subscribe go to www.wellnesstips.ca