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1.
Neuroimage ; 74: 37-44, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23454048

RESUMEN

Musicians show a remarkable ability to interconnect motor patterns and sensory processing in the somatosensory and auditory domains. Many of these processes are specific for the instrument used. We were interested in the cerebral and cerebellar representations of these instrument-specific changes and therefore applied functional magnetic resonance imaging (fMRI) in two groups of instrumentalists with different instrumental training for comparable periods (approximately 15 years). The first group (trumpet players) uses tight finger and lip interaction; the second (pianists as control group) uses only the extremities for performance. fMRI tasks were balanced for instructions (piano and trumpet notes), sensory feedback (keypad and trumpet), and hand-lip interaction on the trumpet. During fMRI, both groups switched between different devices (trumpet or keypad) and performance was combined with or without auditory feedback. Playing the trumpet without any tone emission or using the mouthpiece showed an instrument training-specific activation increase in trumpet players. This was evident for the posterior-superior cerebellar hemisphere, the dominant primary sensorimotor cortex, and the left Heschl's gyrus. Additionally, trumpet players showed increased activity in the bilateral Heschl's gyrus during actual trumpet playing, although they showed significantly decreased loudness while playing with the mouthpiece in the scanner compared to pianists.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiología , Destreza Motora/fisiología , Música , Plasticidad Neuronal/fisiología , Estimulación Acústica , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
2.
Behav Brain Res ; 278: 393-403, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25194587

RESUMEN

We were interested in motor performance gain after unilateral hand motor training and associated changes of cerebral and cerebellar movement representation tested with functional magnetic resonance imaging (fMRI) before and after training. Therefore, we trained the left hand of strongly right-handed healthy participants with a comprehensive training (arm ability training, AAT) over two weeks. Motor performance was tested for the trained and non-trained hand before and after the training period. Functional imaging was performed for the trained and the non-trained hand separately and comprised force modulation with the fist, sequential finger movements and a fast writing task. After the training period the performance gain of tapping movements was comparable for both hand sides, whereas the motor performance for writing showed a higher training effect for the trained hand. fMRI showed a reduction of activation in supplementary motor, dorsolateral prefrontal cortex, parietal cortical areas and lateral cerebellar areas during sequential finger movements over time. During left hand writing lateral cerebellar hemisphere also showed reduced activation, while activation of the anterior cerebellar hemisphere was increased. An initially high anterior cerebellar activation magnitude was a predictive value for high training outcome of finger tapping and visual guided movements. During the force modulation task we found increased activation in the striate. Overall, a comprehensive long-term training of the less skillful hand in healthy participants resulted in relevant motor performance improvements, as well as an intermanual learning transfer differently pronounced for the type of movement tested. Whereas cortical motor area activation decreased over time, cerebellar anterior hemisphere and striatum activity seem to represent increasing resources after long-term motor training.


Asunto(s)
Encéfalo/fisiología , Lateralidad Funcional/fisiología , Mano/fisiología , Aprendizaje/fisiología , Desempeño Psicomotor/fisiología , Adulto , Análisis de Varianza , Ganglios Basales/irrigación sanguínea , Ganglios Basales/fisiología , Encéfalo/irrigación sanguínea , Mapeo Encefálico , Cerebelo/irrigación sanguínea , Cerebelo/fisiología , Corteza Cerebral/irrigación sanguínea , Corteza Cerebral/fisiología , Femenino , Fuerza de la Mano , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Estadística como Asunto , Adulto Joven
3.
Phys Med Biol ; 60(4): 1681-96, 2015 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-25633183

RESUMEN

A commercial active breathing coordinator (ABC) device, employed to hold respiration at a specific level for a predefined duration, was successfully adapted for magnetic resonance imaging (MRI) use for the first time. Potential effects of the necessary modifications were assessed and taken into account. Automatic MR acquisition during ABC breath holding was achieved. The feasibility of MR-ABC thoracic and abdominal examinations together with the advantages of imaging in repeated ABC-controlled breath holds were demonstrated on healthy volunteers. Five lung cancer patients were imaged under MR-ABC, visually confirming the very good intra-session reproducibility of organ position in images acquired with the same patient positioning as used for computed tomography (CT). Using identical ABC settings, good MR-CT inter-modality registration was achieved. This demonstrates the value of ABC, since application of T1, T2 and diffusion weighted MR sequences provides a wider range of contrast mechanisms and additional diagnostic information compared to CT, thus improving radiotherapy treatment planning and assessment.


Asunto(s)
Contencion de la Respiración , Imagen por Resonancia Magnética/métodos , Técnicas de Imagen Sincronizada Respiratorias/métodos , Humanos , Imagen por Resonancia Magnética/instrumentación , Masculino , Posicionamiento del Paciente , Técnicas de Imagen Sincronizada Respiratorias/instrumentación , Transductores
4.
Behav Brain Res ; 223(2): 280-6, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21569800

RESUMEN

Motor performance declines with increasing age and it has been proposed that elder people might compensate for these deficits with increased cerebral activation. However, it is not known, whether increased activation - especially in motor areas of the contralateral and the ipsilateral cerebral hemisphere - might effectively contribute to motor performance or whether it is an ineffective way to counteract age related deficits in the motor system. We tested this question by mapping brain activation during performance of differentially demanding motor tasks in 18 young (mean 25.39 years) and 17 elderly (mean 66.65 years) healthy individuals. We tested a wide range of hand motor tasks from passive wrist movements, fist clenching at different frequencies, to a somatosensory-guided finger pinch task. In the elderly group functional activation was generally increased for all tasks with comparable motor performance for ipsilateral primary and secondary motor areas. The young group showed increased contralateral primary motor cortex activation for the more difficult somatosensory guided precision grip task. We correlated motor performance of the task with high difficulty and comparable performance with fMRI-activation. Elder participants showed a negative correlation for the ipsilateral supplementary motor area (SMA) and for the ipsilateral sensorimotor cortex (SM1). Young participants showed a positive correlation for contralateral SMA and SM1. Our data suggest an increased cerebral recruitment reflects an inefficient response to an age-related higher difficulty of task and is not an effective way to counteract age-related deficits in the motor system.


Asunto(s)
Envejecimiento/fisiología , Envejecimiento/psicología , Desempeño Psicomotor/fisiología , Adulto , Anciano , Encéfalo/fisiología , Femenino , Lateralidad Funcional/fisiología , Fuerza de la Mano/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Motora/fisiología , Destreza Motora , Movimiento/fisiología , Reclutamiento Neurofisiológico/fisiología , Muñeca/fisiología , Adulto Joven
5.
Phys Rev Lett ; 95(5): 052501, 2005 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-16090870

RESUMEN

We report the first measurement of a ratio lambda(beta(b))/lambda(beta(c)) of bound-state ((lambda(beta(b))) and continuum-state (lambda(beta(c))) beta(-)-decay rates for the case of bare 207Tl81+ ions. These ions were produced at the GSI fragment separator FRS by projectile fragmentation of a 208Pb beam. After in-flight separation with the Brho-deltaE-Brho method, they were injected into the experimental storage-ring ESR at an energy of 400.5A MeV, stored, and electron cooled. The number of both the 207Tl81+ ions and their bound-state beta(-)-decay daughters, hydrogen-like 207Pb81+ ions, were measured as a function of storage time by recording their Schottky-noise intensities. The experimental result, lambda(beta(b))/lambda(beta(c)) = 0.188(18), is in very good agreement with the value of 0.171(1) obtained from theory employing spectra of allowed transitions.

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