Recovery of walking in nonambulatory children with chronic spinal cord injuries: Case series.

The immature central nervous system is recognized as having substantial neuroplastic capacity. In this study, we explored the hypothesis that rehabilitation can exploit that potential and elicit reciprocal walking in nonambulatory children with chronic, severe (i.e.

Tongue Force Training Induces Plasticity of the Lingual Motor Cortex in Young Adult and Aged Rats.

Tongue exercise programs are used clinically for dysphagia in aged individuals and have been shown to improve lingual strength. However, the neural mechanisms of age-related decline in swallowing function and its association with lingual strength are not well understood. Using an established rat model of aging and tongue exercise, we hypothesized that the motor cortex of aged rats would have a smaller lingual motor map area than young adult rats and would increase in size as a function of tongue exercise.

Coordinated Plasticity of Synapses and Astrocytes Underlies Practice-Driven Functional Vicariation in Peri-Infarct Motor Cortex.

Motor rehabilitative training after stroke can improve motor function and promote topographical reorganization of remaining motor cortical movement representations, but this reorganization follows behavioral improvements. A more detailed understanding of the neural bases of rehabilitation efficacy is needed to inform therapeutic efforts to improve it. Using a rat model of upper extremity impairments after ischemic stroke, we examined effects of motor rehabilitative training at the ultrastructural level in peri-infarct motor cortex.

Comparison of Electrical and Ultrasound Neurostimulation in Rat Motor Cortex.

Ultrasound (US) is known to non-invasively stimulate and modulate brain function; however, the mechanism of action is poorly understood. This study tested US stimulation of rat motor cortex (100 W/cm, 200 kHz) in combination with epidural cortical stimulation. US directly evoked hindlimb movement.

Translating Genomic Advances to Physical Therapist Practice: A Closer Look at the Nature and Nurture of Common Diseases.

The Human Genome Project and the International HapMap Project have yielded new understanding of the influence of the human genome on health and disease, advancing health care in significant ways. In personalized medicine, genetic factors are used to identify disease risk and tailor preventive and therapeutic regimens. Insight into the genetic bases of cellular processes is revealing the causes of disease and effects of exercise.

Experience with the "good" limb induces aberrant synaptic plasticity in the perilesion cortex after stroke.

Following unilateral stroke, the contralateral (paretic) body side is often severely impaired, and individuals naturally learn to rely more on the nonparetic body side, which involves learning new skills with it. Such compensatory hyper-reliance on the "good" body side, however, can limit functional improvements of the paretic side. In rats, motor skill training with the nonparetic forelimb (NPT) following a unilateral infarct lessens the efficacy of rehabilitative training, and reduces neuronal activation in perilesion motor cortex.

Linking genes to neurological clinical practice: the genomic basis for neurorehabilitation.

Large-scale genomics projects such as the Human Genome Project and the International HapMap Project promise significant advances in the ability to diagnose and treat many conditions, including those with a neurological basis. A major focus of research has emerged in the neurological sciences to elucidate the molecular and genetic basis of various neurological diseases. Indeed, genetic factors are implicated in susceptibility for many neurological disorders, with family history studies providing strong evidence of familial risk for conditions such as stroke, Parkinson's, Alzheimer's, and Huntington's diseases.

Age-dependent reorganization of peri-infarct "premotor" cortex with task-specific rehabilitative training in mice.

Background: The incidence of stroke in adulthood increases with advancing age, but there is little understanding of how poststroke treatment should be tailored by age.

Objective: The goal of this study was to determine if age and task specificity of rehabilitative training affect behavioral improvement and motor cortical organization after stroke.

Methods: Young and aged mice were trained to proficiency on the Pasta Matrix Reaching Task prior to lesion induction in primary motor cortex with endothelin-1.

Effects of aerobic fitness on aging-related changes of interhemispheric inhibition and motor performance.

Physical fitness has been long associated with maintenance and improvement of motor performance as we age. In particular, measures of psychomotor speed and motor dexterity tend to be higher in physically fit aging adults as compared to their sedentary counterparts. Using functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS), we explored the patterns of neural activity that may, in part, account for differences between individuals of varying physical fitness levels.

Targeted motor rehabilitation dissociates corticobulbar versus corticospinal dysfunction in an animal model of Parkinson's disease.

Background: Recent evidence suggests that motor training may be beneficial for slowing the onset of motor impairments in Parkinson's disease (PD).

Objective: To examine the impact of targeted rehabilitation on limb motor and cranial motor function and the corresponding corticospinal and corticobulbar circuits in a rodent model of PD.

Methods: Baseline performance of limb (reaching) and cranial (licking) motor function were established prior to and 6 weeks following unilateral intrastriatal 6-hydroxydopamine (6-OHDA) infusions.

Differential sensitivity of cranial and limb motor function to nigrostriatal dopamine depletion.

The present study determined the differential effects of unilateral striatal dopamine depletion on cranial motor versus limb motor function. Forty male Long Evans rats were first trained on a comprehensive motor testing battery that dissociated cranial versus limb motor function and included: cylinder forepaw placement, single pellet reaching, vermicelli pasta handling; sunflower seed opening, pasta biting acoustics, and a licking task. Following baseline testing, animals were randomized to either a 6-hydroxydopamine (6-OHDA) (n=20) or control (n=20) group.

Behavioral and neurophysiological correlates of striatal dopamine depletion: a rodent model of Parkinson's disease.

Unlabelled: Both limb and cranial motor functions are adversely impacted by Parkinson's disease (PD). While current pharmacological and surgical interventions are effective in alleviating general limb motor symptoms of PD, they have failed to provide significant benefit for cranial motor functions. This suggests that the neuropathologies mediating limb and cranial motor impairments in PD may differ.

Neural plasticity and neurorehabilitation: teaching the new brain old tricks.

Unlabelled: Following brain injury or disease there are widespread biochemical, anatomical and physiological changes that result in what might be considered a new, very different brain. This adapted brain is forced to reacquire behaviors lost as a result of the injury or disease and relies on neural plasticity within the residual neural circuits. The same fundamental neural and behavioral signals driving plasticity during learning in the intact brain are engaged during relearning in the damaged/diseased brain.

Neural plasticity: the biological substrate for neurorehabilitation.

Decades of basic science have clearly demonstrated the capacity of the central nervous system (CNS) to structurally and functionally adapt in response to experience. The field of neurorehabilitation has begun to use this body of work to develop neurobiologically informed therapies that harness the key behavioral and neural signals that drive neural plasticity. The present review describes how neural plasticity supports both learning in the intact CNS and functional improvement in the damaged or diseased CNS.

Striatal dopamine depletion induces forelimb motor impairments and disrupts forelimb movement representations within the motor cortex.

While limb motor deficits of Parkinson's disease are well characterized, the effects of striatal dopamine depletion on the motor cortex is poorly understood. We therefore aimed to 1) examine the effects of striatal dopamine depletion on forelimb function and cortical motor map topography and 2) explore potential relationships between forelimb function and cortical movement representations in an animal model of PD. Twenty-four male Long Evans rats were randomized to control or 6-hydroxydopamine (6-OHDA) groups.

Distributed versus focal cortical stimulation to enhance motor function and motor map plasticity in a rodent model of ischemia.

Background: Motor rehabilitation after cerebral ischemia can enhance motor performance and induce motor map reorganization. Electrical stimulation of the cortex (CS) during rehabilitative training (CS/RT) augments motor map plasticity and confers gains in motor function beyond those observed with motor rehabilitation alone. However, it is unclear how the distribution of electrical stimulation across the cortex accomplishes these changes.

The organization of the forelimb representation of the C57BL/6 mouse motor cortex as defined by intracortical microstimulation and cytoarchitecture.

The organization of forelimb representation areas of the monkey, cat, and rat motor cortices has been studied in depth, but its characterization in the mouse lags far behind. We used intracortical microstimulation (ICMS) and cytoarchitectonics to characterize the general organization of the C57BL/6 mouse motor cortex, and the forelimb representation in more detail. We found that the forelimb region spans a large area of frontal cortex, bordered primarily by vibrissa, neck, shoulder, and hindlimb representations.

The vermicelli and capellini handling tests: simple quantitative measures of dexterous forepaw function in rats and mice.

Previous characterizations of rodent eating behavior have revealed that they use coordinated forepaw movements to manipulate food pieces. We have extended upon this work to develop a simple quantitative measure of forepaw dexterity that is sensitive to lateralized impairments and age-dependent changes. Rodents learn skillful forepaw and digit movements to manage thin pasta pieces, which they eagerly consume.

Motor cortex reorganization across the lifespan.

Unlabelled: The brain is a highly dynamic structure with the capacity for profound structural and functional change. Such neural plasticity has been well characterized within motor cortex and is believed to represent one of the neural mechanisms for acquiring and modifying motor behaviors. A number of behavioral and neural signals have been identified that modulate motor cortex plasticity throughout the lifespan in both the intact and damaged brain.

BDNF val66met polymorphism influences motor system function in the human brain.

Brain-derived neurotrophic factor (BDNF) is important to brain functions such as plasticity and repair. A single nucleotide polymorphism for this growth factor, val(66)met, is common and associated with decreased activity-dependent BDNF release. The current study evaluated the effects of this polymorphism in relation to human brain motor system function, short-term plasticity, and learning.

Brain plasticity and genetic factors.

Brain plasticity refers to changes in brain function and structure that arise in a number of contexts. One area in which brain plasticity is of considerable interest is recovery from stroke, both spontaneous and treatment-induced. A number of factors influence these poststroke brain events.

What do motor "recovery" and "compensation" mean in patients following stroke?

There is a lack of consistency among researchers and clinicians in the use of terminology that describes changes in motor ability following neurological injury. Specifically, the terms and definitions of motor compensation and motor recovery have been used in different ways, which is a potential barrier to interdisciplinary communication. This Point of View describes the problem and offers a solution in the form of definitions of compensation and recovery at the neuronal, motor performance, and functional levels within the framework of the International Classification of Functioning model.