1,720,992 research outputs found
Passive cycling in neurorehabilitation after spinal cord injury: a review
No full textPassive cycling (PC) may represent a potential alternative neurorehabilitation program for patients who are too weak or medically unstable to repeatedly practice active movements. We review here the most important animal and human studies addressing PC after spinal cord injury (SCI)
Transcranial magnetic stimulation and bladder function: a systematic review
No full textOBJECTIVE: We aimed at assessing the usefulness of motor evoked potentials (MEPs) for exploring the integrity of striated sphincters and pelvic floor motor innervation in normal subjects and of repetitive transcranial magnetic stimulation TMS (rTMS) in patients with neurogenic bladder dysfunction. METHODS: A systematic literature search was conducted using PubMed and Embase. RESULTS: We identified, reviewed and discussed 11 articles matching the inclusion criteria. CONCLUSIONS: The assessment of MEPs could represent a useful tool in the investigation of patients with urologic disorders. High frequency rTMS can improve detrusor contraction and/or urethral sphincter relaxation in patients with multiple sclerosis and bladder dysfunction. Low frequency (LF) rTMS seems to be an effective treatment of neurogenic lower urinary tract dysfunctions in subjects with Parkinson's disease and possibly other neurodegenerative disorders. Furthermore, rTMS might have the potential to restore bladder and bowel sphincter function after incomplete spinal cord injury. LF rTMS could also relieve some symptoms of bladder pain syndrome and chronic pelvic pain. SIGNIFICANCE: The clinical applicability of MEPs appears to be questionable, since a poor reproducibility was detected for all pelvic floor muscles. The use of rTMS in this field is emerging and the results of a few preliminary studies should be replicated in controlled, randomized studies with larger sample sizes
Altered response to repetitive transcranial magnetic stimulation in patients with chronic primary insomnia
No full textBackground: We aimed at evaluating the amplitude changes of the motor evoked potentials (MEPs) induced by of low-frequency (LF) repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (M1) in10 patients with primary insomnia (PI) and in 10 age-matched healthy controls. Methods: Median peak-to-peak MEP amplitudes were assessed in all subjects at three times: at baseline (T0), after the first train of a single rTMS session (T1), and after the whole rTMS procedure (T2). This consists of 20 trains of 1 Hz stimulation with 50 stimuli per train and an intertrain interval of 30 s. Results: Resting motor threshold (RMT) and MEPs amplitude did not differ between the two groups at T0. A reduction of MEP size was observed at both T1 and T2 in all subjects, but this was significantly less pronounced in patients than in control subjects. Conclusions: The lack of MEP inhibition reflects an altered response to LF rTMS in patients with PI. These rTMS findings are indicative of an altered cortical plasticity in inhibitory circuits within M1 in PI. Subjects with PI exhibited an impairment of the LTD-like mechanisms induced by inhibitory rTMS, thus providing further support to the involvement of GABA neurotransmission in the pathophysiology of PI
Motor cortex plasticity in subjects with mild cognitive impairment
No full text[no abstract available
Abnormal short-latency synaptic plasticity in the motor cortex of subjects with Becker muscular dystrophy: a rTMS study
No full textWe used repetitive transcranial magnetic stimulation (rTMS) to further investigate motor cortex excitability in 13 patients with Becker muscular dystrophy (BMD), six of them with slight mental retardation. RTMS delivered at 5Hz frequency and suprathreshold intensity progressively increases the size of motor evoked potentials (MEPs) in healthy subjects; the rTMS-induced facilitation of MEPs was significantly reduced in the BMD patients mentally retarded or classified as borderline when compared with age-matched control subjects and the BMD patients with normal intelligence. The increase in the duration of the cortical silent period was similar in both patient groups and controls. These findings suggest an altered cortical short-term synaptic plasticity in glutamate-dependent excitatory circuits within the motor cortex in BMD patients with intellectual disabilities. RTMS studies may shed new light on the physiological mechanisms of cortical involvement in dystrophinopathies
Transcranial magnetic stimulation and gait disturbances in Parkinson's disease: A systematic review
No full textTranscranial magnetic stimulation (TMS) may offer a reliable means of characterizing important pathophysiologic aspects of motor impairments in Parkinson's disease (PD). Moreover, high-frequency repetitive TMS (rTMS), especially if delivered bilaterally over motor cortical regions, can have beneficial effects on parkinsonian motor symptoms. However, only a few studies have investigated the effects of rTMS on freezing of gait (FOG) and other gait disturbances in PD. We aimed at investigating in this narrative review the usefulness of TMS for exploring the pathophysiology of gait impairment and at evaluating the therapeutic effects of rTMS in this context. The combination of rTMS and treadmill training was found to enhance the effect of physical therapy. Use of an H-coil enables stimulation of deep regions of the brain (for example medial prefrontal cortex) and may be used as a target for add-on therapy in the future. In contrast, theta burst stimulation has proven to be ineffective in treating gait disturbances in PD patients. Dual-mode NIBS, in particular preconditioning motor cortex rTMS by transcranial direct current stimulation, might also represent a novel therapeutic approach for patients with gait disturbances. Recent studies suggest that the supplementary motor area could be an appropriate target for brain stimulation when treating PD patients with FOG. Further large sample and well-designed clinical studies are required to evaluate how the possible positive effects of rTMS can be sustained over time and to determine the optimal stimulation protocols including target, stimulation intensity/duration and number of sessions
Repetitive transcranial magnetic stimulation in traumatic brain injury: evidence from animal and human studies
Full text linkWe provide here the first systematic review on the studies dealing with repetitive transcranial magnetic stimulation (rTMS) for traumatic brain injury (TBI) in animals and humans. Several experimental studies in animal models have explored with promising results the use of rTMS to enhance neuroprotection and recovery after TBI. However, there are surprisingly few studies that have obtained substantial evidence regarding effects of rTMS in humans with TBI, many of them are case reports investigating the heterogeneous conditions linked to TBI. The most studies have investigated the effects of rTMS in subjects with post-traumatic depression and variable effects have been observed. rTMS has been proposed as an experimental approach for the treatment of disorders of consciousness (DOC), but in subjects with TBI therapeutic effects on DOC have also been variously documented. Beneficial effects have been reported in subjects with cognitive/emotional disturbances and auditory dysfunction (tinnitus and hallucinations), although the results are somewhat conflicting. rTMS applied over the left prefrontal cortex may relieve, at least transiently, post-traumatic headache. Isolated rTMS studies have been performed in TBI patients with motor impairment, chronic dizziness or pain. Especially whether provided in combination, rTMS and neurorehabilitation may be synergistic in the potential to translate experimental findings in the clinical practice. In order to reach definitive conclusions, well-designed randomized controlled studies with larger patient samples, improved design and optimized rTMS setup, are warranted to verify and corroborate the initial promising findings
Disinhibition of sensory cortex in patients with amyotrophic lateral sclerosis
No full textIn patients with amyotrophic lateral sclerosis (ALS) a motor cortical hyperexcitability has been reported in transcranial magnetic stimulation studies, but little is known about the neuronal excitability in other cortical areas. The aim of the present study was the functional evaluation of the sensory cortex in subjects with ALS by assessing the high-frequency somatosensory evoked potentials (HF-SEP). No significant HF-SEP abnormalities were observed in ALS patients with disease duration of < 2 years, while the patients with a disease duration of > 2 years we found a large amplitude reduction of post-synaptic HF-SEP burst. Since post-synaptic burst of HF-SEP is thought to reflect the activity of cortical inhibitory interneurons, our findings provide further evidence that disinhibition is a primary characteristic of ALS that also involves the somatosensory cortex
Abnormal cortical synaptic plasticity in minimal hepatic encephalopathy
No full textMinimal hepatic encephalopathy (MHE) represents the earliest stage of hepatic encephalopathy (HE). MHE is characterized by cognitive function impairment in the domains of attention, vigilance and integrative function, while obvious clinical manifestations are lacking. In the present study, we aimed at assessing whether subjects with MHE showed alterations in synaptic plasticity within the motor cortex. Previous findings suggest that learning in human motor cortex occurs through long-term potentiation (LTP)-like mechanisms. We employed therefore the paired associative stimulation (PAS) protocol by transcranial magnetic stimulation (TMS), which is able to induce LTP-like effects in the motor cortex of normal subjects. Fifteen patients with MHE and 15 age- and sex-matched cirrhotic patients without MHE were recruited. PAS consisted of 180 electrical stimuli of the right median nerve paired with a single TMS over the hotspot of right abductor pollicis brevis (APB) at an ISI of 25ms (PAS25). We measured motor evoked potentials (MEPs) before and after each intervention for up to 30min. In healthy subjects the PAS25 protocol was followed by a significant increase of the MEP amplitude. On the contrary, in patients with MHE the MEP amplitude was slightly reduced after PAS. These findings demonstrated that associative sensorimotor plasticity, an indirect probe for motor learning, is impaired in MHE patients
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