Body sway and sensory motor coupling adaptation in children: Effects of distance manipulation

The purpose of this investigation was to examine coupling between visual information and body sway in children and young adults at various distances from a moving room front wall. Sixty children (from 4 to 14 years old) and 10 young adults stood upright inside a moving room that was oscillated at .2 and .5 Hz, at distances of .25, .5, 1, and 1.5 m from a front wall. Visual information induced body sway in all participants in all conditions. Young children swayed more than older participants, whether the moving room was oscillated or not. Coupling between visual information and body sway became stronger and the room movement influence became weaker with age. Up to the age of 10, coupling strength between visual information and body sway and the room movement influence were distance dependent. Postural control development appears to be dependent on how children reweight the contribution of varying sensory cues available in environment in order to control body sway. (C) 2007 Wiley Periodicals, Inc.

Analysis of the Hb(b)over-bar coupling constant and CP-violation effects at the future e(+)e(-) collider

The e(+)e(-)-->b (B) over bar nu(ν) over bar process, where nu is an electron, muon, or tau-lepton neutrino, is analyzed in detail for the general form of the coupling constant of a Higgs boson with b quarks, with the (m(b)/v)(a + igamma(5)b) parameterization of the Hb (b) over bar interaction. This process is shown to be highly sensitive to this coupling constant. Experiments at the future with roots = 500-GeV linear collider will provide limits of 2 and 20% for deviations of the parameters a and b, respectively, from their Standard Model values. Results concerning the e(+)e(-)-->b (b) over bar nu(ν) over bar process in combination with the independent measurements of the partial width Gamma(H --> b (b) over bar) can testify to the CP origin of the Higgs sector of the theory. (C) 2003 MAIK Nauka/Interperiodica.

Physical activity and postural control in the elderly: Coupling between visual information and body sway

Background: Aging is characterized by a decline in the postural control performance, which is based on a coherent and stable coupling between sensory information and motor action. Therefore, changes in postural control in elderlies can be related to changes in this coupling. In addition, it has been observed that physical activity seems to improve postural control performance in elderlies. These improvements can be due to changes in the coupling between sensory information and motor action related to postural control. Objective: the purpose of this study was to verify the coupling between visual information and body sway in active and sedentary elderlies. Methods: Sixteen sedentary elderlies ( SE), 16 active elderlies ( AE) and 16 young adults ( YA) were asked to stand upright inside a moving room in two experimental conditions: ( 1) discrete movement and ( 2) continuous movement of the room. Results: In the continuous condition, the results showed that the coupling between the movement of the room and body sway was stronger and more stable for SE and AE compared to YA. In the discrete condition, SE showed larger body displacement compared to AE and YA. Conclusions: SE have more difficulty to discriminate and to integrate sensory information than AE and YA indicating that physical activity may improve sensory integration. Copyright (C) 2005 S. Karger AG, Basel.

Coupling between muscle activities and muscle torques during horizontal-planar arm movements with direction reversal

In this study we investigated the hypothesis that the simple set of rules used to explain the modulation of muscle activities during single-joint movements could also be applied for reversal movements of the shoulder and elbow joints. The muscle torques of both joints were characterized by a triphasic impulse. The first impulse of each joint accelerated the limb to the target and was generated by an initial burst of the muscles activated first (primary mover). The second impulse decelerated the limb to the target, reversed movement direction and accelerated the limb back to the initial position, and was generated by an initial burst of the muscles activated second (secondary movers). A third impulse, in each joint, decelerated the limb to the initial position due to the generation of a second burst of the primary movers. The first burst of the primary mover decreased abruptly, and the latency between the activation of the primary and secondary movers varied in proportion with target distances for the elbow, but not for the shoulder muscles. All impulses and bursts increased with target distances and were well coupled. Therefore, as predicted, the bursts of muscle activities were modulated to generate the appropriate level of muscle torque. (C) 2005 Elsevier Ltd. All rights reserved.

The effects of anxiety on visual search, movement kinematics, and performance in table tennis: A test of Eysenck and Calvo's processing efficiency theory

Processing efficiency theory predicts that anxiety reduces the processing capacity of working memory and has detrimental effects on performance. When tasks place little demand on working memory, the negative effects of anxiety can be avoided by increasing effort. Although performance efficiency decreases, there is no change in performance effectiveness. When tasks impose a heavy demand on working memory, however, anxiety leads to decrements in efficiency and effectiveness. These presumptions were tested using a modified table tennis task that placed low (LWM) and high (HWM) demands on working memory. Cognitive anxiety was manipulated through a competitive ranking structure and prize money. Participants' accuracy in hitting concentric circle targets in predetermined sequences was taken as a measure of performance effectiveness, while probe reaction time (PRT), perceived mental effort (RSME), visual search data, and arm kinematics were recorded as measures of efficiency. Anxiety had a negative effect on performance effectiveness in both LWM and HWM tasks. There was an increase in frequency of gaze and in PRT and RSME values in both tasks under high vs. low anxiety conditions, implying decrements in performance efficiency. However, participants spent more time tracking the ball in the HWM task and employed a shorter tau margin when anxious. Although anxiety impaired performance effectiveness and efficiency, decrements in efficiency were more pronounced in the HWM task than in the LWM task, providing support for processing efficiency theory.

Perception-action coupling in infants with down syndrome: Effects of experience and practice

This study examined the effects of experience and practice on the coupling between visual information and trunk sway in infants with Down syndrome (DS). Five experienced and five novice sitters were exposed to a moving room, which was oscillated at 0.2 and 0.5 Hz. Infants remained in a sitting position and data were collected on the first, fourth, and seventh days. On the first day, experienced sitters were more influenced by room oscillation than were novices. On the following days, however, the influence of room oscillation decreased for experienced but increased for novice sitters. These results suggest that the relationship between sensory information and motor action in infants with DS can be changed with experience and practice.

Social movement, public policy changes and partnerships building for local development

O artigo discute a influência do movimento social rural sobre as mudanças na política de apoio ao pequeno produtor rural e para a criação de parcerias entre o Governo e as Organizações Locais para o desenvolvimento local na Amazônia, em particular no estado do Pará. O objetivo do artigo é examinar a parceria como um resultado de um processo interativo entre as mudanças nas políticas públicas e as demandas dos movimentos sociais. O artigo mostra que embora os movimentos sociais façam parte de uma relação conflituosa entre o Estado e a sociedade civil, tais movimentos no estado do Pará foram uma pré-condição para mudanças na política pública, estrutura de financiamento e prioridades das agencias regionais que resultaram em proposições para cooperação entre o Governo e as Organizações Locais em nível municipal.

Sleep deprivation affects sensorimotor coupling in postural control of young adults

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Adaptation of sensorimotor coupling in postural control Is impaired by sleep deprivation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Functional coupling of sensorimotor and associative areas during a catching ball task: a qEEG coherence study

Abstract Background Catching an object is a complex movement that involves not only programming but also effective motor coordination. Such behavior is related to the activation and recruitment of cortical regions that participates in the sensorimotor integration process. This study aimed to elucidate the cortical mechanisms involved in anticipatory actions when performing a task of catching an object in free fall. Methods Quantitative electroencephalography (qEEG) was recorded using a 20-channel EEG system in 20 healthy right-handed participants performed the catching ball task. We used the EEG coherence analysis to investigate subdivisions of alpha (8-12 Hz) and beta (12-30 Hz) bands, which are related to cognitive processing and sensory-motor integration. Results Notwithstanding, we found the main effects for the factor block; for alpha-1, coherence decreased from the first to sixth block, and the opposite effect occurred for alpha-2 and beta-2, with coherence increasing along the blocks. Conclusion It was concluded that to perform successfully our task, which involved anticipatory processes (i.e. feedback mechanisms), subjects exhibited a great involvement of sensory-motor and associative areas, possibly due to organization of information to process visuospatial parameters and further catch the falling object.

Conservation of the RNA Transport Machineries and Their Coupling to Translation Control across Eukaryotes

Restriction of proteins to discrete subcellular regions is a common mechanism to establish cellular asymmetries and depends on a coordinated program of mRNA localization and translation control. Many processes from the budding of a yeast to the establishment of metazoan embryonic axes and the migration of human neurons, depend on this type of cell polarization. How factors controlling transport and translation assemble to regulate at the same time the movement and translation of transported mRNAs, and whether these mechanisms are conserved across kingdoms is not yet entirely understood. In this review we will focus on some of the best characterized examples of mRNA transport machineries, the "yeast locasome" as an example of RNA transport and translation control in unicellular eukaryotes, and on the Drosophila Bic-D/Egl/Dyn RNA localization machinery as an example of RNA transport in higher eukaryotes. This focus is motivated by the relatively advanced knowledge about the proteins that connect the localizing mRNAs to the transport motors and the many well studied proteins involved in translational control of specific transcripts that are moved by these machineries. We will also discuss whether the core of these RNA transport machineries and factors regulating mRNA localization and translation are conserved across eukaryotes.

A New Approach for Automatic Removal of Movement Artifacts in Near-Infrared Spectroscopy Time Series by Means of Acceleration Data

Abstract: Near-infrared spectroscopy (NIRS) enables the non-invasive measurement of changes in hemodynamics and oxygenation in tissue. Changes in light-coupling due to movement of the subject can cause movement artifacts (MAs) in the recorded signals. Several methods have been developed so far that facilitate the detection and reduction of MAs in the data. However, due to fixed parameter values (e.g., global threshold) none of these methods are perfectly suitable for long-term (i.e., hours) recordings or were not time-effective when applied to large datasets. We aimed to overcome these limitations by automation, i.e., data adaptive thresholding specifically designed for long-term measurements, and by introducing a stable long-term signal reconstruction. Our new technique (“acceleration-based movement artifact reduction algorithm”, AMARA) is based on combining two methods: the “movement artifact reduction algorithm” (MARA, Scholkmann et al. Phys. Meas. 2010, 31, 649–662), and the “accelerometer-based motion artifact removal” (ABAMAR, Virtanen et al. J. Biomed. Opt. 2011, 16, 087005). We describe AMARA in detail and report about successful validation of the algorithm using empirical NIRS data, measured over the prefrontal cortex in adolescents during sleep. In addition, we compared the performance of AMARA to that of MARA and ABAMAR based on validation data.

Perfil del jugador de rugby a partir de un screening de movimiento funcional como herramienta de prevención

En la última década numerosos trabajos de investigación científica han logrado dejar en claro la ventajas generadas a partir del entrenamiento de las capacidades condicionales de manera funcional, dejando atrás las tendencias en donde los patrones fundamentales de movimiento humano quedaban fuera del análisis del rendimiento deportivo. El interés que ha despertado en nuestro equipo de trabajo, como readaptadores del movimiento, nos lleva a indagar bajo esta perspectiva y las metodologías implementadas para su programación. El presente artículo intenta dar una perspectiva de trabajo a partir del desarrollo de un perfil preventivo, desarrollado en base a un screening funcional de movimiento. Utilizamos para ello, una matriz de datos diseñada a partir del análisis del movimiento su correcta y eficiente ejecución. Como contrapartida esto nos facilita la detección de patrones de movimiento afuncionales, patrones que no supongan una ejecución eficaz, que devendrá en puntos débiles para nuestros deportistas. Nuestro Universo de investigación son jugadores del Plantel Superior de clubes de Rugby de la ciudad de La Plata, que se desempeñan en la Primera División de la Unión de Rugby de Buenos Aires. La matriz de datos presentada utiliza como bases el Functional Movement Screen, diseñado por el fisioterapeuta Gray Cook y el Dr. Lee Burton, con adaptaciones desarrolladas, para objetivar datos en el análisis de los patrones biomecánicos humanos, con respecto al desempeño funcional y la prevención de lesiones deportivas

Perfil del jugador de rugby a partir de un screening de movimiento funcional como herramienta de prevención

En la última década numerosos trabajos de investigación científica han logrado dejar en claro la ventajas generadas a partir del entrenamiento de las capacidades condicionales de manera funcional, dejando atrás las tendencias en donde los patrones fundamentales de movimiento humano quedaban fuera del análisis del rendimiento deportivo. El interés que ha despertado en nuestro equipo de trabajo, como readaptadores del movimiento, nos lleva a indagar bajo esta perspectiva y las metodologías implementadas para su programación. El presente artículo intenta dar una perspectiva de trabajo a partir del desarrollo de un perfil preventivo, desarrollado en base a un screening funcional de movimiento. Utilizamos para ello, una matriz de datos diseñada a partir del análisis del movimiento su correcta y eficiente ejecución. Como contrapartida esto nos facilita la detección de patrones de movimiento afuncionales, patrones que no supongan una ejecución eficaz, que devendrá en puntos débiles para nuestros deportistas. Nuestro Universo de investigación son jugadores del Plantel Superior de clubes de Rugby de la ciudad de La Plata, que se desempeñan en la Primera División de la Unión de Rugby de Buenos Aires. La matriz de datos presentada utiliza como bases el Functional Movement Screen, diseñado por el fisioterapeuta Gray Cook y el Dr. Lee Burton, con adaptaciones desarrolladas, para objetivar datos en el análisis de los patrones biomecánicos humanos, con respecto al desempeño funcional y la prevención de lesiones deportivas

Perfil del jugador de rugby a partir de un screening de movimiento funcional como herramienta de prevención

En la última década numerosos trabajos de investigación científica han logrado dejar en claro la ventajas generadas a partir del entrenamiento de las capacidades condicionales de manera funcional, dejando atrás las tendencias en donde los patrones fundamentales de movimiento humano quedaban fuera del análisis del rendimiento deportivo. El interés que ha despertado en nuestro equipo de trabajo, como readaptadores del movimiento, nos lleva a indagar bajo esta perspectiva y las metodologías implementadas para su programación. El presente artículo intenta dar una perspectiva de trabajo a partir del desarrollo de un perfil preventivo, desarrollado en base a un screening funcional de movimiento. Utilizamos para ello, una matriz de datos diseñada a partir del análisis del movimiento su correcta y eficiente ejecución. Como contrapartida esto nos facilita la detección de patrones de movimiento afuncionales, patrones que no supongan una ejecución eficaz, que devendrá en puntos débiles para nuestros deportistas. Nuestro Universo de investigación son jugadores del Plantel Superior de clubes de Rugby de la ciudad de La Plata, que se desempeñan en la Primera División de la Unión de Rugby de Buenos Aires. La matriz de datos presentada utiliza como bases el Functional Movement Screen, diseñado por el fisioterapeuta Gray Cook y el Dr. Lee Burton, con adaptaciones desarrolladas, para objetivar datos en el análisis de los patrones biomecánicos humanos, con respecto al desempeño funcional y la prevención de lesiones deportivas