The complex phenomenological understanding of dystonia has transcended from the clinics to genetics, imaging and neurophysiology. One way in which electrophysiology will impact into the clinics are cases wherein a dystonic clinical presentation may not be typical or a "forme fruste" of the disorder. Indeed, the physiological imprints of dystonia are present regardless of its clinical manifestation. Underpinnings in the understanding of dystonia span from the peripheral, segmental and suprasegmental levels to the cortex, and various electrophysiological tests have been applied in the course of time to elucidate the origin of dystonia pathophysiology. While loss of inhibition remains to be the key finding in this regard, intricacies and variabilities exist, thus leading to a notion that perhaps dystonia should best be gleaned as network disorder. Interestingly, the complex process has now spanned towards the understanding in terms of networks related to the cerebellar circuitry and the neuroplasticity. What is evolving towards a better and cohesive view will be neurophysiology attributes combined with structural dynamic imaging. Such a sound approach will significantly lead to better therapeutic modalities in the future.

• Klíčová slova
• Brain plasticity, Dystonia, Network disorder, Neurophysiology,
• MeSH
• dystonické poruchy * MeSH
• dystonie * MeSH
• lidé MeSH
• mozeček MeSH
• mozková kůra MeSH
• neurofyziologie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

This study investigates the role of the dorsal/sensorimotor striatum in visuomotor integration (i.e., the transformation of internal visual information about letter shapes into motor output) during handwriting. Twenty healthy participants underwent fMRI scanning with tasks consisting of self-paced handwriting of alphabetically ordered single letters and simple dots, with both tasks performed without visual feedback. Functional connectivity (FC) from these two tasks was compared to demonstrate the difference between coordinated activity arising during handwriting and the activity during a simpler motor condition. Our study focused upon the writing-specific cortico-striatal network of preselected regions of interest consisting of the visual word form area (VWFA), anterior intraparietal sulcus/superior parietal lobule, striatum, premotor cortex/Exner's area, and primary and supplementary motor regions. We observed systematically increased task-induced cortico-striatal and cortico-cortical FC. This increased synchronization of neural activity between the VWFA, i.e., the visual cortical area containing information about letter shapes, and the frontoparietal motor regions is mediated by the striatum. These findings suggest the involvement of the striatum in integrating stored letter-shape information with motor planning and execution during handwriting.

• Klíčová slova
• Basal ganglia, Functional connectivity, Handwriting, Striatum, Visuomotor integration, fMRI,
• MeSH
• corpus striatum diagnostické zobrazování   fyziologie   MeSH
• dospělí MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• mladý dospělý MeSH
• mozková kůra diagnostické zobrazování   fyziologie   MeSH
• nervová síť diagnostické zobrazování   fyziologie   MeSH
• pohybová aktivita fyziologie   MeSH
• psaní rukou * MeSH
• psychomotorický výkon fyziologie   MeSH
• rozpoznávání obrazu fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We studied the appearance of cognitive event-related potentials (ERPs) and event-related de/synchronizations (ERD/S) in the subthalamic nucleus (STN) and globus pallidus internus (GPi). We particularly focused on the rare non-target (distractor) stimuli processing. ERPs and ERD/S in the alpha and beta frequency range were analyzed in seven Parkinson's disease patients and one primary dystonia patient with implanted deep brain stimulation (DBS) electrodes. A visual three-stimulus protocol was used (frequent stimulus, target stimulus, and distractor). The non-target and distractor-related waveforms manifested similar shapes. A specific positive ERP peak around 200 ms and a low alpha frequency ERS were detected from the STN as a response to the distractor stimuli in six of the patients with Parkinson's disease and also in the primary dystonia patient's GPi. This positivity probably reflects an attentional orienting response to the distractor stimuli. The STN and GPi are probably involved in attentional cerebral networks.

• MeSH
• elektroencefalografie metody   MeSH
• evokované potenciály fyziologie   MeSH
• globus pallidus fyziologie   MeSH
• hluboká mozková stimulace přístrojové vybavení   metody   MeSH
• implantované elektrody MeSH
• lidé středního věku MeSH
• lidé MeSH
• nucleus subthalamicus fyziologie   MeSH
• Parkinsonova nemoc patofyziologie   terapie   MeSH
• pozornost fyziologie   MeSH
• senioři 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
• srovnávací studie MeSH

We studied whether the cognitive event-related potentials (ERP) in the subthalamic nucleus (STN) are modified by the modulation of the inferior frontal cortex (IFC) and the dorsolateral prefrontal cortex (DLPFC) with repetitive transcranial magnetic stimulation (rTMS). Eighteen patients with Parkinson's disease who had been implanted with a deep brain stimulation (DBS) electrode were included in the study. The ERPs were recorded from the DBS electrode before and after the rTMS (1 Hz, 600 pulses) over either the right IFC (10 patients) or the right DLPFC (8 patients). The ERPs were generated by auditory stimuli. rTMS over the right IFC led to a shortening of ERP latencies from 277 +/- 14 ms (SD) to 252 +/- 19 ms in the standard protocol and from 296 +/- 17 ms to 270 +/- 20 ms in the protocol modified by a higher load of executive functions (both P < 0.01). The application of rTMS over the DLPFC and the sham stimulation over the IFC showed no significant changes. The shortening of ERP latency after rTMS over the right IFC reflected the increase in the speed of the cognitive process. The rTMS modulation of activity of the DLPFC did not influence the ERP. Connections (the IFC-STN hyperdirect pathway) with the cortex that bypass the BG-thalamocortical circuitries could explain the position of the STN in the processing of executive functions.

• MeSH
• akustická stimulace MeSH
• analýza rozptylu MeSH
• čelní lalok patofyziologie   MeSH
• elektroencefalografie MeSH
• evokované potenciály fyziologie   MeSH
• exekutivní funkce fyziologie   MeSH
• implantované elektrody MeSH
• lidé středního věku MeSH
• lidé MeSH
• mapování mozku MeSH
• nervové dráhy patofyziologie   MeSH
• nucleus subthalamicus patofyziologie   MeSH
• Parkinsonova nemoc patofyziologie   MeSH
• počítačové zpracování signálu MeSH
• psychomotorický výkon fyziologie   MeSH
• reakční čas MeSH
• sluchová percepce fyziologie   MeSH
• transkraniální magnetická stimulace metody   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH