S16-3 Praxis movements: the role of the beta band in higher-order motor control

2010 ◽  
Vol 121 ◽  
pp. S29
Author(s):  
L.A. Wheaton
Keyword(s):  
1995 ◽  
Vol 8 (1) ◽  
pp. 27-49 ◽  
Author(s):  
Dana M. Schneider ◽  
Richard A. Schmidt
Keyword(s):  

2021 ◽  
pp. 1-18
Author(s):  
Sicong Liu ◽  
Jillian M. Clements ◽  
Elayna P. Kirsch ◽  
Hrishikesh M. Rao ◽  
David J. Zielinski ◽  
...  

Abstract The fusion of immersive virtual reality, kinematic movement tracking, and EEG offers a powerful test bed for naturalistic neuroscience research. Here, we combined these elements to investigate the neuro-behavioral mechanisms underlying precision visual–motor control as 20 participants completed a three-visit, visual–motor, coincidence-anticipation task, modeled after Olympic Trap Shooting and performed in immersive and interactive virtual reality. Analyses of the kinematic metrics demonstrated learning of more efficient movements with significantly faster hand RTs, earlier trigger response times, and higher spatial precision, leading to an average of 13% improvement in shot scores across the visits. As revealed through spectral and time-locked analyses of the EEG beta band (13–30 Hz), power measured prior to target launch and visual-evoked potential amplitudes measured immediately after the target launch correlate with subsequent reactive kinematic performance in the shooting task. Moreover, both launch-locked and shot/feedback-locked visual-evoked potentials became earlier and more negative with practice, pointing to neural mechanisms that may contribute to the development of visual–motor proficiency. Collectively, these findings illustrate EEG and kinematic biomarkers of precision motor control and changes in the neurophysiological substrates that may underlie motor learning.


2018 ◽  
Vol 75 (10) ◽  
pp. 3521-3540 ◽  
Author(s):  
Etienne Dunn-Sigouin ◽  
Tiffany Shaw

Recent work has shown that extreme stratospheric wave-1 negative heat flux events couple with the troposphere via an anomalous wave-1 signal. Here, a dry dynamical core model is used to investigate the dynamical mechanisms underlying the events. Ensemble spectral nudging experiments are used to isolate the role of specific dynamical components: 1) the wave-1 precursor, 2) the stratospheric zonal-mean flow, and 3) the higher-order wavenumbers. The negative events are partially reproduced when nudging the wave-1 precursor and the zonal-mean flow whereas they are not reproduced when nudging either separately. Nudging the wave-1 precursor and the higher-order wavenumbers reproduces the events, including the evolution of the stratospheric zonal-mean flow. Mechanism denial experiments, whereby one component is fixed to the climatology and others are nudged to the event evolution, suggest higher-order wavenumbers play a role by modifying the zonal-mean flow and through stratospheric wave–wave interaction. Nudging all tropospheric wave precursors (wave-1 and higher-order wavenumbers) confirms they are the source of the stratospheric waves. Nudging all stratospheric waves reproduces the tropospheric wave-1 signal. Taken together, the experiments suggest the events are consistent with downward wave propagation from the stratosphere to the troposphere and highlight the key role of higher-order wavenumbers.


1983 ◽  
Vol 50 (3) ◽  
pp. 658-670 ◽  
Author(s):  
A. D. McClellan

The buccal mass of the gastropod Pleurobranchaea is used during a regurgitation response that consists of a writhing phase interrupted by brief periodic bouts of a vomiting phase (17, 20). During transitions from writhing to vomiting, specific changes occur in the motor pattern (19, 20). Evidence is presented suggesting that at least some of the initiation or "command" neurons for vomiting reside in the buccal ganglia. The present paper examines the role of two candidate vomiting-initiation cells, the ventral white cells (VWC) and midganglionic cells (MC), in the buccal ganglia of isolated nervous systems. Stimulation of single VWCs activates a vomiting motor pattern, consisting in part of alternating buccal root activity. Furthermore, the VWCs fire in high-frequency bursts during episodes (i.e., bouts) of this same vomiting pattern. Mutual reexcitation between the VWCs and motor pattern generator (MPG) appears to produce the accelerated buildup and maintenance of vomiting rhythms. Brief stimulation of single MCs "triggers" bouts of a vomiting motor pattern, but the membrane potential of this cell is only modulated during this same pattern, at least in the isolated nervous system. It is proposed that in intact animals the MCs are activated by sensory inputs and briefly excite the VWC-MPG network, thereby turning on the mutual reexcitatory mechanism mentioned above and switching the output pattern. A general implication for gastropod research is that higher order neurons that activate buccal root activity cannot automatically be given the function of "feeding command neuron," as some cells clearly control other responses, such as vomiting.


2015 ◽  
Vol 25 (6) ◽  
pp. 744-776 ◽  
Author(s):  
Apostolos Giovanis ◽  
Pinelopi Athanasopoulou ◽  
Evangelos Tsoukatos

Purpose – The purpose of this paper is to extend the well-established nomological network of service quality-relationship quality-customer loyalty by introducing service fairness – a distinct service evaluation concept. Specifically, the study aims to investigate the impact of service fairness on relationship quality as a complementary to service quality driver, and the direct and indirect effect of service fairness on customer loyalty in the presence of service quality and relationship quality in a no failure/recovery effort service context. Design/methodology/approach – A telephone survey of a random sample of 408 customers of auto repair and maintenance services was implemented using a structured questionnaire with established scales. Data were analyzed with partial least squares path methodology, a structural equation modeling methodology. Findings – Interactional fairness is the most important formative determinant of customers’ overall fairness perception, followed by procedural and distributive fairness. Relationship quality measured as a higher order construct, made of satisfaction; trust; affective and calculative commitment, is the main determinant of customer loyalty. Also, it partially mediates, along with service quality, the relationship between service fairness and customer loyalty and fully mediates the effect of service quality on customer loyalty. Finally, service fairness has the highest overall effect on customer loyalty. Research limitations/implications – The sample is industry-specific and this may affect generalizability of findings. Also, the cross-sectional design adopted does not reflect temporal changes. Practical implications – Interactional fairness is of utmost importance to customers of the investigated industry. So, customers should be fairly treated at every point of contact. Also, service quality is heavily affected by service fairness. Thus, fair service leads to high-perceived service quality. Third, service quality affects customer loyalty only through relationship quality. Only when service quality is coupled by long-term quality relationships, signs of customer loyalty appear. Finally, service fairness influences customer loyalty mainly through service and relationship quality and has the highest overall effect on customer loyalty. So, fairly treating customers is crucial for developing long-term relationships that lead to customer loyalty. Originality/value – The role of service fairness in the service quality-relationship quality-customer loyalty chain is investigated and using a higher order construct for relationship quality.


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