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Damage to the motor cortex induced by stroke or traumatic brain injury (TBI) can result in chronic motor deficits. For the development and improvement of therapies, animal models which possess symptoms comparable to the clinical population are used. However, the use of experimental animals raises valid ethical and methodological concerns. To decrease discomfort by experimental procedures and to increase the quality of results, non-invasive and sensitive rodent motor tests are needed. A broad variety of rodent motor tests are available to determine deficits after stroke or TBI. The current review describes and evaluates motor tests that fall into three categories: Tests to evaluate fine motor skills and grip strength, tests for gait and inter-limb coordination and neurological deficit scores. In this review, we share our thoughts on standardized data presentation to increase data comparability between studies. We also critically evaluate current methods and provide recommendations for choosing the best behavioral test for a new research line. [ABSTRACT FROM AUTHOR]

Objective Stroke is one of the leading causes of physical disability due to damage of the motor cortex or the corticospinal tract. In the present study we set out to investigate the role of adaptations in the corticospinal pathway for motor recovery during the subacute phase after stroke. Methods We examined 19 patients with clinically diagnosed stroke and 18 controls. The patients had unilateral mild to moderate weakness of the hand. Each patient attended two sessions at approximately 3 days (acute) and 38 days post stroke (subacute). Task-related changes in the communication between motor cortex and muscles were evaluated from coupling in the frequency domain between EEG and EMG during movement of the paretic hand. Results Corticomuscular coherence (CMC) and intermuscular coherence (IMC) were reduced in patients as compared to controls. Paretic hand motor performance improved within 4–6 weeks after stroke, but no change was observed in CMC or IMC. Conclusions CMC and IMC were reduced in patients in the early phase after stroke. However, changes in coherence do not appear to be an efficient marker for early recovery of hand function following stroke. Significance This is the first study to demonstrate sustained reduced coherence in acute and subacute stroke. [ABSTRACT FROM AUTHOR]

Objectives Trigeminal neuralgia (TN) is the most common cranial neuralgia in adults, with a slight prevalence in women. Antiepileptic drugs represent the mainstay of the medical treatment, whereas microvascular decompression is the best option in case of neurovascular conflict. Although these treatments showed a good rate of efficacy, they can be contraindicated in some patients and >50% of patients undergoing these treatments will present recurrence of pain in the following months. In this majority of patients, pain becomes chronic and can severely affect their quality of life and cause cognitive disturbances, such as anxiety and depression. Methods The purpose of this study was to review the efficacy and safety of current treatment modalities for TN, as well as to propose a multimodal approach for those patients presenting with a chronic form of TN. Results Current treatment modalities have been reviewed. Actual pain evaluation systems and the neuropsychologic features of TN have been analyzed in order to propose an alternative treatment algorithm. Discussion Chronic pain can also lead to the misperception of patients' own selves leading to enhanced pain perception and altering therapeutic outcomes. Thus, there is the need to define a personalized multimodal approach of treatment, taking into account other available TN therapies and the neuropsychologic aspect of chronic pain. [ABSTRACT FROM AUTHOR]

Highlights: [•] We induced a severe frontal motor cortex ablation in adult rats. [•] We examined the effects of GH treatment and rehabilitation on brain recovery. [•] Early administration of GH led to significant motor recovery. [•] Nestin immunoreactivity appeared in the contralateral motor cortex of GH-treated injured rats. [•] GH plus rehabilitation increased neurogenesis and brain plasticity in injured rats. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The individual motor elements presumed to be essential for motor development were determined from spontaneous movements involving the entire body of normal term and preterm infants. Then, diagnostic items for motor abnormality in infants with periventricular leukomalacia (PVL) were investigated. Methods: Video recordings of 24 healthy term infants, 21 normal preterm infants (8 males, 13 females; median gestational age 30weeks; median birth weight 1216g) and 14 preterm infants with PVL (6 males, 8 females; median gestational age 30weeks; median birth weight 1360g) were analyzed. Results: In healthy term infants, predominant shoulder rotation was noticed until 1month of age. After 2months of age, isolated movements of the shoulder, elbow, hip, knee, and ankle frequently emerged. In preterm infants with PVL at the corrected age of 2months, startle response and predominant shoulder rotation were more frequently seen and isolated neck, shoulder, elbow, hip, knee, and ankle movements were less frequently seen than in the normal preterm infants (Fisher’s exact test, p <0.025). Interpretation: At 2months of age, isolated movements evolve, and their failure to occur is suggested to be a useful sign for the diagnosis of cerebral motor disorders. [Copyright &y& Elsevier]

Abstract: Restoring movement control after central nervous system injury requires reconnecting the brain and spinal motoneurons, and doing so with sufficient precision and strength to enable robust voluntary muscle recruitment. Whereas the connection between the upper motoneuron in motor cortex and alpha-motoneurons was thought to be the only important connection for normal motor function in humans, we know that a multiplicity of motor circuits are recruited during normal motor control. Multiplicity of functionally important motor circuits points to the myriad possibilities of intervention that restorative neurology can turn to for repairing motor systems connections to recover movement control after injury. New motor systems repair strategies in animal models and humans are tapping into distributed motor control functions of the spinal cord; neural activity-based approaches, especially for corticospinal tract repair; and circuit-selective activation approaches. I focus on studies harnessing activity-based therapeutic approaches to promote sprouting of spared corticospinal tract axons after injury and redirecting potentially maladaptive plasticity. I discuss that we can see on the near horizon, many different strategies for repairing motor systems connections after injury. [Copyright &y& Elsevier]

Abstract: Motor cortex injuries in adulthood lead to poor performance in behavioral tasks sensitive to limb movements in the rat. We have shown previously that motor cortex injury on day 10 or day 55 allow significant spontaneous recovery but not injury in early adolescence (postnatal day 35 “P35”). Previous studies have indicated that injection of basic fibroblast growth factor (FGF-2) enhances behavioral recovery after neonatal cortical injury but such effect has not been studied following motor cortex lesions in early adolescence. The present study undertook to investigate the possibility of such behavioral recovery. Rats with unilateral motor cortex lesions were assigned to two groups in which they received FGF-2 or bovine serum albumin (BSA) and were tested in a number of behavioral tests (postural asymmetry, skilled reaching, sunflower seed manipulation, forepaw inhibition in swimming). Golgi–Cox analysis was used to examine the dendritic structure of pyramidal cells in the animals’ parietal (layer III) and forelimb (layer V) area of the cortex. The results indicated that rats injected with FGF-2 (but not BSA) showed significant behavioral recovery that was associated with increased dendritic length and spine density. The present study suggests a role for FGF-2 in the recovery of function following injury during early adolescence. [Copyright &y& Elsevier]

Abstract: Functional reorganization of brain cortical areas occurs following stroke in humans, and many instances of this plasticity are associated with recovery of function. Rodent studies have shown that following a cortical stroke, neurons in uninjured areas of the brain are capable of sprouting new axons into areas previously innervated by injured cortex. The pattern and extent of structural plasticity depend on the species, experimental model, and lesion localization. In this study, we examined the pattern of axon sprouting in spinal cord after a localized lesion which selectively targeted the primary motor cortex in adult mice. We subjected mice to a stereotaxic-guided photothrombotic stroke of the left motor cortex, followed 2 weeks later by an injection of the neuronal tracer biotinylated dextran amine (BDA) into the uninjured right motor cortex. BDA-positive axons originating from the uninjured motor cortex were increased in the gray matter of the right cervical spinal cord in stroke mice, compared to sham control mice. These results show that axon sprouting can occur in the spinal cord of adult wild-type mice after a localized stroke in motor cortex. [Copyright &y& Elsevier]

Photothrombotic lesions were produced in the rat primary motor cortex, and the brain excitability was assessed in a paired-pulse stimulation protocol by transcranial recording, in parallel at 16 points of the frontal cortex, including the insulted and the surrounding areas. The cortical lesion reduced the inhibition in the extended frontal cortex, with a delay of a few minutes. Unilateral facial nerve transection, however, accelerated the widespread disinhibition. Although the mechanism is not clear in detail, both peripheral and central injury-induced disinhibition may have a significant impact on the recovery of the function. [Copyright &y& Elsevier]