Sunday, October 17, 2010
The four lobes (frontal, temporal, parietal and occipital) of the brain are each responsible for different functions of the body. The right and left hemispheres of the brain control opposite sides of the body. Sensory information travels up to the brain via the spinal cord where it is processed. The thalamus relays this sensory information (except smell) to the cerebral cortex, this information is then send to different parts of the brain. When sensory information gets process a motor response is given to specific body parts.
Neuroplasticity is the brain’s ability to change within the environment and to store information in memory associated with learning. Plasticity is a part of normal functional development in the brain from the time of birth to maturity. Neuroplasticity happens by learning new skills or past experiences throughout the lifespan.
“Neuroplasticity occurs in the brain under two primary conditions:
1. During normal brain development when the immature brain first begins to process sensory information through adulthood. In stages of normal development the brain goes through a transition from childhood when it is able to learn and make new connections easily, to adulthood when it is a bit more settled in its structure, but can focus on a single problem for longer and carry out more complex thought processes this is called “synaptic pruning”. This synaptic pruning happens in adolescence when the body is making the transition from childhood to adulthood.
2. As an adaptive mechanism to compensate for lost function and/or to maximize remaining functions in the event of brain injury. These mechanisms that are involved in neuroplasticity stand out as important contributors to the developing brain’s ability to acquire new information, change in response to environmental stimulation, and recover from injury [Johnston et al., 2009].”
If a child receives an injury to the left frontal lobe of the brain before adolescence, the right frontal lobe which is undamaged takes over the function of the left frontal lobe which is now damaged and lost its functions. On the other hand, if an adult where to receive the same injury in the same area of the brain, the lost of function may be more severe because the brain has lost the plasticity to transfer the functions of that part of the brain to the other.
Neuroplasticity is the brain trying to reorganize itself. This reorganization is due to local changes in that area of the brain and is dependent on stimulation in areas where information is processed. “Synapses are specialized junctions between multiple neurons or between neurons and other cells they interact with. Synapse formation, strength, and modulation are all dependent on... electrical activity generated by release of chemical neurotransmitters.”(Moskowitz,C. 2009).
Information is processed in 3 ways:
1) Selecting neurons (nerve cells). Neurons make new or different connections with other neurons.
2) Changing connections could happen by the brain using other areas to compensate for the lost of one area.
3) Releasing more neurotransmitter which leads to increasing the firing rate of neurons.
``Activity based restorative therapy (ABRT) is ... evidence-based rehabilitative interventions utilized under the premise that impairment repair leads to improvement in disability and handicap `` (Moskowitz,C. 2009) . ABRT is a therapy that can be used in both OT and PT for improving normal functional movement using neuroplasticity. `` ABRTs tools can simply be described as follows: (a) patterned motor activation (i.e., locomotor training, functional electrical stimulated (FES) ergometry), (b) nonpatterned motor activation (i.e., recruitment and strengthening, task specific training), and (c) sensory stimulation (i.e., sensorimotor therapy) (Moskowitz,C. 2009).``
The following interventions were used in the rehabilitation of the patient who the inspiration for this blog. As a result of him sustaining an injury the left side of his brain, he was left with abnormal tone and muscle weakness in his right upper and lower extremity. The goal of rehabilitation for this patient in physical and occupational therapy was to maximize and/or regain functional movement as a result of neuroplasticity.
1)`` Constraint-induced movement therapy (CIMT) is an intervention for patients with hemiplegia in which they wear are straining mitt on the less-affected hand while engaging in repetitive task practice and behavioural shaping with the hemiplegic hand.”(Johnson 2009) CIMT requires the patients to have some functions of the affected hand which is placed a sling for at 6 hours a day. The idea is to encourage use of the weaker hand to do daily activities; this therapy uses neuroplasticity by making new connections in the brain, releasing neuroplasticity and using new or different neurons within the brain. In using the affected hand to perform daily tasks such as picking up a cup, filling it with water and taking a drink the part of the brain responsible for motor functions, memory and sequencing which may have been affected is now been stimulated. Not only is CIMT used to improve function of the weaker but it is also dependent on the environment where activities are done because it can enhance neuroplasticity. Repetitive stimulation is the basis of neuroplasticity.
2) “Motor impairments following stroke ... leading cause of disability in adults. Motor therapies involve ... motor functions by minimising impairment or developing suitable adaptation strategies skill learning must be present to promote... plasticity when using motor learning as an activity most of the recovery of function after a stroke may represent actual relearning of the skills with the injured brain (Moskowitz,C. 2009).”
Neuromuscular Electrical Stimulation (NMES) is used in both PT and OT to recover motor function. NMES is the application of electrical stimuli to a group of muscles by passing an electrical impulse through electrodes placed on the skin over the targeted muscle or muscles. This therapy can be used on both the upper and lower extremity. NMES is to activate muscles in early rehabilitation but can later be progressed with repetitive functional activity. NMES promote neuroplasticity in the early stages of rehab using electricity to recruit new neurons within the affect area of the brain. Plasticity using NMES is a means to achieve active, repetitive movement.
For this patient with right side weakness in both his shoulder and ankle NMES was used to regain normal functional movement such as picking up a cup or walking.
The goal of rehab was to improve the patient’s capabilities by achieving functional goals. The potential to regain functional movement is due to neuroplasticity. This plasticity was achieved by using repetitive daily activities in a stimulating environment.
Chudler E. H., (No date). Brain Plasticity: what is it? In Neuroscience for kids. Retrieved Monday, October 4, 2010, from http://faculty.washington.edu/chudler/plast.html#fact
Moskowitz C. ,(March 23, 2009). Teen Brains Clear Out Childhood Thoughts. In Live Science. Retrieved October 2, 2010, from http://www.livescience.com/health/090323-adolescent-brain.html
Beam J.,(2008) What is Neuromuscular Electrical Stimulation? Retrieved Monday, October 4,2010 from http://www.wisegeek.com/what-is-neuromuscular-electrical-stimulation.htm
Articles and Databases
Sadowsky, Cristina L., 2009, Activity-based restorative therapies: Concepts and applications in spinal cord injury-related neurorehabilitation. Developmental disabilities research review, volume 15 issue number2 pages 112-116. Retrieved October 1st from Academic Search Complete
Johnston, Michael V., 2009, Plasticity in the developing brain: Implications for rehabilitation. Developmental disabilities research reviews, volume 15 issue 2 pages 94-101 Retrieved October 1st from Academic Search Complete
Bolognini, Nadia, 2009, Using non-invasive brain stimulation to augment motor training-induced plasticity. Journal of neuroengineering and rehabilitation volume 6 pages 1-13 Retrieved October 1st from Academic Search Complete
Pitts D.G., O'Brien S.P., 2008, Splinting the hand to enhance motor control and brain plasticity, Topics in stroke rehabilitation, pages 446-467 Retrieved October 1st from Academic Search Complete
Dobkin H.B., 1993 Neuroplasticity
Key to Recovery After Central Nervous System Injury, the Western Journal of Medicine, pages 56-60
Pictures and videos
Video courtesy of Youtube.com
Images courtesy of Google.ca