ABSTRACT: In dystonic and spastic movement disorders, abnormalities of motor control and somatosensory processing as well as cortical modulations associated with clinical improvement after botulinum toxin A (BoNT-A) treatment have been reported, but electrophysiological evidence remains controversial. In the present observational study, we aimed to uncover central correlates of post-stroke spasticity (PSS) and BoNT-A-related changes in the sensorimotor cortex by investigating the cortical components of somatosensory evoked potentials (SEPs). Thirty-one chronic stroke patients with PSS of the upper limb were treated with BoNT-A application into the affected muscles and physiotherapy. Clinical and electrophysiological evaluations were performed just before BoNT-A application (W0), then 4 weeks (W4) and 11 weeks (W11) later. PSS was evaluated with the modified Ashworth scale (MAS). Median nerve SEPs were examined in both upper limbs with subsequent statistical analysis of the peak-to-peak amplitudes of precentral P22/N30 and postcentral N20/P23 components. At baseline (W0), postcentral SEPs were significantly lower over the affected cortex. At follow up, cortical SEPs did not show any significant changes attributable to BoNT-A and/or physiotherapy, despite clear clinical improvement. Our results imply that conventional SEPs are of limited value in evaluating cortical changes after BoNT-A treatment and further studies are needed to elucidate its central actions.

• MeSH
• botulotoxiny typ A aplikace a dávkování   MeSH
• cévní mozková příhoda komplikace   patofyziologie   MeSH
• dospělí MeSH
• horní končetina inervace   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• následné studie MeSH
• nervosvalové látky aplikace a dávkování   MeSH
• nervus medianus účinky léků   patofyziologie   MeSH
• rehabilitace po cévní mozkové příhodě metody   MeSH
• senioři MeSH
• somatosenzorické evokované potenciály účinky léků   MeSH
• somatosenzorické korové centrum účinky léků   patofyziologie   MeSH
• svalová spasticita diagnóza   farmakoterapie   etiologie   patofyziologie   MeSH
• terapie cvičením metody   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• pozorovací studie MeSH

OBJECTIVE: The restless legs syndrome (RLS) is characterized by sensory-motor symptoms which usually occur predominantly at rest in the evening and at night. It is assumed that this circadian rhythm is caused by low dopamine levels in the evening. Yet, it has never been investigated whether RLS patients show diurnal variations in cognitive functions modulated by dopamine and what neurophysiological and functional neuroanatomical processes underlie such modulations. METHODS: We used a Simon task combined with EEG and source localization to investigate whether top-down response selection and/or automatic visuo-motor priming are subject to diurnal changes in RLS patients, as compared to matched healthy controls. RESULTS: We found that RLS patients showed better task performance due to reduced visuo-motor priming in the evening, as reflected by smaller early lateralized readiness potential (e-LRP) amplitudes and decreased activation of the superior parietal cortex and premotor cortex. Top-down response selection and early attentional processing were unaffected by RLS. CONCLUSIONS: Counterintuitively, RLS patients show enhanced task performance in the evening, i.e. when experiencing dopaminergic deficiency. Yet, this may be explained by deficits in visuo-motor priming that lead to reduced false response tendencies. SIGNIFICANCE: This study reveals a counterintuitive circadian variation of cognitive functions in RLS patients.

• MeSH
• cirkadiánní rytmus * MeSH
• dopamin metabolismus   MeSH
• elektroencefalografie MeSH
• kognice MeSH
• lidé středního věku MeSH
• lidé MeSH
• opakované seznamování se skutečností * MeSH
• psychomotorický výkon * MeSH
• senioři MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• studie případů a kontrol MeSH
• syndrom neklidných nohou metabolismus   patofyziologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Converging data on focal dystonias suggest a widespread disorder of somatosensory processing. The aims of our study were, first, to assess somatosensory activation patterns in cervical dystonia (CD) beyond the representation of the affected body parts and, second, to search for task-related activation changes induced by botulinum toxin type-A (BoNT-A) therapy. Functional magnetic resonance imaging (MRI) during electrical median nerve stimulation was employed in seven CD patients and nine controls; the examination was repeated 4 weeks after BoNT-A application to dystonic neck muscles. The pretreatment activation map of patients showed activation in the contralateral primary somatosensory cortex, but missing activation in the secondary somatosensory cortex and insula, in contrast to controls and patients after treatment. Clinically significant effect of BoNT-A therapy was associated with a significant increase of BOLD response in the contralateral secondary somatosensory, insular, and inferior parietal cortices. The posttreatment somatosensory maps of patients did not significantly differ from controls. This study has brought evidence of widespread disruption of somatosensory processing in CD and its modification with BoNT-A therapy.

• MeSH
• botulotoxiny typ A farmakologie   terapeutické užití   MeSH
• dospělí MeSH
• injekce intramuskulární metody   MeSH
• krční svaly účinky léků   inervace   patofyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nervosvalové látky farmakologie   terapeutické užití   MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• somatosenzorické poruchy farmakoterapie   patofyziologie   MeSH
• tortikolis farmakoterapie   patofyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVE: Patients with writer's cramp (WC) were studied for differences in cortical activation during movements likely to induce WC (complex movements) and movements which rarely lead to dystonia (simple movements). METHODS: Eleven WC patients (10F, 1M, mean age 41.5 ± (SD)7.2 years) and eleven age matched controls were examined for Blood oxygenation-level dependent (BOLD) 1.5 T fMRI. The complex task consisted of writing a single letter or random drawing using an especially adapted joystick with the line of trajectory visualized or hidden. The simple task consisted of self-initiated fingers flexion/extension using the affected hand. RESULTS: Unlike the controls, WC patients performing complex movements exhibited a lower BOLD signal in the primary sensorimotor cortex and in the posterior parietal cortex bilaterally. A hypoactivation was also observed in the right secondary somatosensory area, in the right anterior insula and in the left premotor cortex (p < 0.05 corrected). No significant inter-group differences were found for simple movements. CONCLUSIONS: Although WC patients' complex movements during fMRI were never associated with dystonic cramp, they exhibited an abnormally low cortical activity. This phenomenon was not observed in simple movements and was unrelated to the character of handwriting or to visual feedback. SIGNIFICANCE: Our results support the dualistic behavior in the sensorimotor system in WC.

• MeSH
• algoritmy MeSH
• antidyskinetické látky terapeutické užití   MeSH
• biomechanika MeSH
• botulotoxiny terapeutické užití   MeSH
• dospělí MeSH
• dystonické poruchy farmakoterapie   patofyziologie   MeSH
• feedback psychologický MeSH
• kyslík krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• motorické korové centrum patofyziologie   MeSH
• mozková kůra patofyziologie   MeSH
• počítačové zpracování obrazu MeSH
• pohyb fyziologie   MeSH
• psaní rukou MeSH
• psychomotorický výkon fyziologie   MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• světelná stimulace MeSH
• temenní lalok patofyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Since the somatosensory system is believed to be affected in focal dystonia, we focused on the modulation of the primary somatosensory cortex (SI) induced by repetitive transcranial magnetic stimulation (rTMS) in order to improve symptoms of writer's cramp. Patients with writer's cramp (N=9 in the pilot study and N=11 in the advanced study) were treated with 30-minute 1 Hz real- or sham-rTMS of the SI cortex every day for 5 days. Before and after rTMS, 1.5 T fMRI was examined during simple hand movements. While in the pilot study the rTMS coil was navigated over the SI cortex with a maximum of blood oxygenation-level dependent (BOLD) signal induced by passive movement, patients in the advanced study had the coil above the postcentral sulcus. After real-rTMS, 4 pilot study patients and 10 advanced study patients experienced subjective and objective improvement in writing, while only minimal changes were observed after sham-rTMS. Patients involved in the active movement task exhibited a rTMS-induced BOLD signal increase bilaterally in the SI cortex, posterior parietal cortex and in the supplementary motor area (P<0.001 corrected). After sham-rTMS, no BOLD signal changes were observed. In conclusion, 1 Hz rTMS of the SI cortex can improve writer's cramp while increasing the cortical activity in both hemispheres. Handwriting improved in most patients, as well as the subjective benefit, and lasted for 2-3 weeks. The beneficial effects of rTMS paralleled the functional reorganization in the SI cortex and connected areas, reflecting the impact of somatosensory system on active motion control.

• MeSH
• biologické modely MeSH
• dospělí MeSH
• dystonické poruchy terapie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• mapování mozku MeSH
• mozková kůra patofyziologie   účinky záření   MeSH
• pilotní projekty MeSH
• placeba MeSH
• psaní rukou MeSH
• somatosenzorické korové centrum patofyziologie   účinky záření   MeSH
• transkraniální magnetická stimulace MeSH
• záření MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH

Spinal cord stimulation (SCS) consisting of electrical stimulation of the dorsal spinal cord using epidural electrodes has been shown to relieve chronic neuropathic pain. To analyze the cerebral activation patterns related to SCS, and to evaluate the effects of SCS on the processing of acute experimental pain, we performed functional magnetic resonance imaging (fMRI) on eight patients suffering from failed back surgery syndrome who were also being treated with SCS for severe pain in their legs and lower back. Three types of stimulation were used, each lasting 36s: (i) SCS, (ii) heat pain (HP) applied to the leg affected by neuropathic pain, and (iii) simultaneous HP and SCS. During SCS, we found increased activation of the medial primary sensorimotor cortex somatotopically corresponding to the foot and/or perineal region, contralateral posterior insula, and the ipsilateral secondary somatosensory cortex (S2). Decreased activation was seen in the bilateral primary motor cortices and the ipsilateral primary somatosensory cortex corresponding to the shoulder, elbow and hand. Compared to separately presented HP and SCS, simultaneous HP and SCS showed statistically significant activation of the bilateral inferior temporal cortex and the ipsilateral cerebellar cortex. The activation of the primary motor cortex, insula and S2 during SCS may directly interfere with the processing of neuropathic pain. When SCS is associated with heat pain, the paralimbic association cortex and cerebellum show activation exceeding the sum of activations resulting from separate SCS and heat pain stimulation. The explanation of this could possibly rest with the continuous comparisons of simultaneous pain and somatosensory sensations occurring in a single dermatome.

• MeSH
• bérec MeSH
• bolest etiologie   MeSH
• dospělí MeSH
• elektrostimulační terapie škodlivé účinky   metody   MeSH
• financování organizované MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• mícha patofyziologie   MeSH
• motorické korové centrum patofyziologie   MeSH
• mozek patofyziologie   MeSH
• neuralgie terapie   MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• vysoká teplota škodlivé účinky   MeSH
• záda chirurgie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH

Parkinson's disease (PD) affects speech, including respiration, phonation, and articulation. We measured the blood oxygen level-dependent (BOLD) response to overt sentence reading in: (1) 9 treated female patients with mild to moderate PD (age; mean 66.0 +/- 11.6 years, mean levodopa equivalent 583.3 +/- 397.9 mg) and (2) 8 age-matched healthy female controls (age; mean 62.2 years +/- 12.3). Speech was recorded in the scanner to assess which brain regions underlie variations in the initiation and paralinguistic aspects (e.g., pitch, loudness, and rate) of speech production in the two groups. There were no differences in paralinguistic aspects of speech except for speech loudness; it was lower in PD patients compared with that in controls, when age was used as a covariate. In both groups, we observed increases in the BOLD response (reading-baseline) in brain regions involved in speech production and perception. In PD patients, as compared with controls, we found significantly higher BOLD signal in the right primary orofacial sensorimotor cortex and more robust correlations between the measured speech parameters and the BOLD response to reading, particularly, in the left primary orofacial sensorimotor cortex. These results might reflect compensatory mechanisms and/or treatment effects that take place in mild to moderately ill PD patients with quality of speech yet comparable with that of age-matched controls. (c) 2007 Movement Disorder Society.

• MeSH
• akustická stimulace metody   MeSH
• akustika řeči MeSH
• financování organizované MeSH
• kyslík krev   MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie metody   MeSH
• mapování mozku MeSH
• Parkinsonova nemoc patologie   patofyziologie   MeSH
• počítačové zpracování obrazu metody   MeSH
• řeč fyziologie   MeSH
• senioři MeSH
• somatosenzorické korové centrum krevní zásobení   patofyziologie   MeSH
• statistika jako téma MeSH
• studie případů a kontrol MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH

BACKGROUND: The exact origin of focal dystonias has not been elucidated so far. Aberrant plasticity of the brain cortex is suspected to be a crucial factor in the development of this group of movement disorders. The aim of this article is to summarize recent findings on the etiopathogenesis of focal hand dystonias with a focus on the role of abnormal cortical plasticity. METHODS AND RESULTS: A search of the literature mainly from 1995 to 2005 was done using the PubMed and Ovid search engines. English-language articles were identified using the following keywords: focal hand dystonia or writer's cramp and cortical plasticity, sensorimotor, imaging. Additional references were found through bibliography reviews of relevant articles. The data from neurophysiological and imaging studies, as well as clinical observation, in focal hand dystonia suggest multiple failures at different levels of the somatosensory and motor systems, particularly in the brain cortex. This disorders lead to attenuation of inhibitory and fortification of excitatory processes. CONCLUSIONS: The emerging theory presumes that a maladaptive plasticity of brain cortex with abnormal sensorimotor intergration can evolve in predisposed individuals. Consequent methods of management of focal hand dystonias are outlined.

• MeSH
• dystonické poruchy patofyziologie   MeSH
• lidé MeSH
• mozková kůra patofyziologie   MeSH
• neuroplasticita MeSH
• ruka MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

• MeSH
• dystonie diagnóza   patofyziologie   MeSH
• finanční podpora výzkumu jako téma MeSH
• kosterní svaly zranění   MeSH
• lidé MeSH
• motorické neurony fyziologie   MeSH
• mozková kůra patofyziologie   MeSH
• nervosvalová vřeténka parazitologie   MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• Check Tag
• lidé MeSH

• MeSH
• somatosenzorické korové centrum patofyziologie   MeSH
• vestibulární funkční testy metody   MeSH
• závrať diagnóza   terapie   MeSH