Motor priming in neurorehabilitation

Only 6 pages and 4.5 years old and I am absolutely positive that your doctor knows nothing about this.  So you are on your own to figure out how this might help you recover. Our fucking failures of stroke associations are doing nothing with this, they do nothing for survivors.

Motor priming in neurorehabilitation

 Mary Ellen Stoykov, PhD, OTR/L, and Sangeetha Madhavan, PT, PhD
Priming is a type of implicit learning wherein a stimulus prompts achange in behavior. Priming has been long studied in the field of psychology. More recently, rehabilitation researchers have studied motor  priming as a possible way to facilitate motor learning. For example, priming of the motor cortex is associated with changes in neuroplasticity that are associated with improvements in motor performance.Of the numerous motor priming paradigms under investigation, only a few are practical for the current clinical environment, and the optimal priming modalities for specific clinical presentations are not known.Accordingly, developing an understanding of the various types of motor priming paradigms and their underlying neural mechanisms is an important step for therapists in neurorehabilitation.  Most importantly,an understanding of the methods and their underlying mechanisms is essential for optimizing rehabilitation outcomes. The future of neurorehabilitation is likely to include these priming methods, which aredelivered prior to or in conjunction with primary neurorehabilitation therapies. In this Special Interest article, we discuss those priming paradigms that are supported by the greatest amount of evidence, including (i) stimulation-based priming, (ii) motor imagery and action observation,(iii)sensory priming,(iv)movement based priming,and (v) pharmacological priming.
VideoAbstractavailable.
(seeSupplementalDigitalContent1,http://links.lww.com/JNPT/A86) for more insights from the authors.
Key words:
 Motor cortex, priming, brain stimulation, Bilateral movement, Sensory stimulation
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INTRODUCTION
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riming is defined as a change in behavior based on previous stimuli. Priming, which may occur after a single learning episode, is a type of implicit learning. The role of implicit learning in physical therapy (PT) has been the subject of recent investigation.
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Priming-induced learning is
Department of Occupational Therapy, Rush University Medical Center,Chicago,Illinois(M.E.S.);and Department of PhysicalTherapy, University of Illinois in Chicago (S.M.).This manuscript was funded, in part, by a training award from a Multi-Center K12 Award funded by NIH (K12 HD055931) for the first author.The authors declare no conflicts of interest.Supplemental digital content is available for this article. Direct URL citation appears in the printed text and is provided in the HTML and PDF versionsof this article on the journal’s Web site (www.jnpt.org).
Correspondence:
 Mary Ellen Stoykov, PhD, OTR/L, Department of Occupational Therapy, Rush University Medical Center,600SPaulinaSt,Chicago,IL 60612 (mary_stoykov@rush.edu).Copyright
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2015 Neurology Section, APTA.ISSN: 1557-0576/15/3901-0033DOI: 10.1097/NPT.0000000000000065
different from other types of implicit learning because skill-learning requires repetition.
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Studies of priming originated in psychology, but have since been investigated in neuroscience,neurorehabilitation, and cognitive neuroscience using behav-ioral and brain mapping techniques. These studies, both translational and clinical, have been examining motor priming asa tool for inducing neuroplasticity and enhancing the effects of rehabilitation. Priming can be categorized as a restorative intervention that reduces impairment by targeting underlying neural mechanisms in neurological disorders.
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Priming stimuli can be from the same modality as the accompanying task(modal-specific) or from a different modality(cross-modal). An example of modal-specific priming is bilat-eralmirrorsymmetricalmovement(aformofmovement-based  priming) that is performed prior to a motor task practice and has been found to increase the rate of motor learning in neuro-logically healthy subjects.
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Cross-modal priming can also beused to enhance motor learning. For example, semantic priming, reading relevant words describing an action, can produce more efficient movements in young, neurologically healthy adults compared with a control condition.
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Although there are examples of cross-modal priming producing positive results,results from studies in the psychology literature have reported that the effects of priming are smaller with cross-modal prim-ing as compared with priming using the same modality.
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Initial interest in priming was fueled by popular psychology research completed several decades ago that included the isolation of memory subtypes and examination of individuals with amnesia.
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Priming is an action that generates a type of implicit memory; therefore, researchers were surprised when individuals with amnesia had intact priming as this indicates that priming, unlike explicit memory, is not controlled by the medial temporal lobe. In contrast to explicit memory, priming is believed to arise from facilitated neural processing in a variety of cortical regions that are specific to the stimulus and the accompanying task. For example, the posterior cortex (extratriatal area) is implicated in perceptual priming, whereas the prefrontal cortex is implicated in conceptually based semantic priming.
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The general theory underlying priming is that the brain,that has been primed by prior activation is generally more responsive to the accompanying or subsequent training. Priming presupposes that enhanced neural activity before or during training can facilitate the activation of long-term potentiation-(LTP) or long-term depression-(LTD) like mechanisms.
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Two proposed neural mechanisms for priming include
 gating
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homeostatic plasticity
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Gating occurs by disinhibition of intracortical inhibitory circuits as a result of an increase in
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calcium in the targeted cortical neurons. Gating occurs instan-taneously and is achieved
 concurrently with
 motor training.
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Homeostatic plasticity is the ability of neurons to increaseexcitability after a period of low synaptic activity (and con-versely, to decrease excitability after a period of high synapticactivity) and is related to changes in postsynaptic glutamatereceptors.
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The time scale of homeostatic metaplasticity,in comparison to gating, is protracted, and hence the resting state of neurons is modulated
 prior to
 motor training to induce synaptic plasticity. Neural mechanisms mediating motor priming varyaccording to priming method. However, they may produce similar effects that may include increased excitability or normalization of inhibition, which coincide with improvements in motor behavior.
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Methodsofprimingthemotorcortexthataremost relevant to rehabilitation include (1) stimulation-based  priming
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; (2) motor imagery and action observation
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;(3) manipulation of sensory input
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; (4) movement-based  priming
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; and (5) pharmacology-based priming.
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Studies examining priming for the primary motor cortex (M1) are increasing in number. Hence, it is important for neurorehabilitation professionals to be aware of the basic principles of  priming and how they influence motor training (Table 1).A search of the literature through December 2013 was performed using the search engines: PubMed, Web of Science, and Ovid. Key words used were “priming” combined with one of the following terms: “brain plasticity,” “motor recovery,” “TMS,” “rTMS,” “tDCS,” “PAS,” “PNS,” “motor imagery,” “action observation,” “movement based,” “bilateral movements,” unilateral movements, “aerobic exercise,”“pharmacology based,” “sensory priming,” “peripheral nerve stimulation,” “temporary functional deafferentation,” and “vibration.” Peer-reviewed articles were selected if they met the following criteria: (1) written in English, (2) involved more than 1 human participant, and (3) included at least 1 motor performance-based outcome measure, and (4) fit the defini-tion of “priming” as described in the “Introduction” section.Papers that were cited in the selected articles, such as mechanistic or studies using animal models, were also included for  background information. We also included studies that cited the selected articles. The 5 priming paradigms are described later.