scholarly journals Does different activation between the medial and the lateral gastrocnemius during walking translate into different fascicle behavior?

2021 ◽  
Author(s):  
Raphaël Hamard ◽  
Jeroen Aeles ◽  
Nicole Y. Kelp ◽  
Romain Feigean ◽  
François Hug ◽  
...  
Keyword(s):  
Mechanical Behavior ◽  
Surface Electromyography ◽  
Muscle Activation ◽  
Medial Gastrocnemius ◽  
Functional Difference ◽  
Group Level ◽  
Lateral Gastrocnemius ◽  
Functional Roles ◽  
Individual Level ◽  
The Individual

The functional difference between the medial gastrocnemius (MG) and lateral gastrocnemius (LG) during walking in humans has not yet been fully established. Although evidence highlights that the MG is activated more than the LG, the link with potential differences in mechanical behavior between these muscles remains unknown. In this study, we aimed to determine whether differences in activation between the MG and LG translate into different fascicle behavior during walking. Fifteen participants walked at their preferred speed under two conditions: 0% and 10% incline treadmill grade. We used surface electromyography and B-mode ultrasound to estimate muscle activation and fascicle dynamics in the MG and LG. We observed a higher normalized activation in the MG than LG during stance, which did not translate into greater MG normalized fascicle shortening. However, we observed significantly less normalized fascicle lengthening in the MG than LG during early stance, which matched with the timing of differences in activation between muscles. This resulted in more isometric behavior of the MG, which likely influences the muscle-tendon interaction and enhances the catapult-like mechanism in the MG compared to the LG. Nevertheless, this interplay between muscle activation and fascicle behavior, evident at the group level, was not observed at the individual level as revealed by the lack of correlation between the MG-LG differences in activation and MG-LG differences in fascicle behavior. The MG and LG are often considered as equivalent muscles but the neuromechanical differences between them suggest that they may have distinct functional roles during locomotion.

Reply to Connor and Evers (2020): Critique of the Bias of Crowds Model Simply Restates the Model

2020 ◽  
Author(s):  
Keith Payne ◽  
Heidi A. Vuletich ◽  
Kristjen B. Lundberg
Keyword(s):  
Implicit Bias ◽  
Group Level ◽  
Systemic Racism ◽  
Individual Level ◽  
The Core ◽  
Psychological Science ◽  
Implicit Biases ◽  
The Individual

The Bias of Crowds model (Payne, Vuletich, & Lundberg, 2017) argues that implicit bias varies across individuals and across contexts. It is unreliable and weakly associated with behavior at the individual level. But when aggregated to measure context-level effects, the scores become stable and predictive of group-level outcomes. We concluded that the statistical benefits of aggregation are so powerful that researchers should reconceptualize implicit bias as a feature of contexts, and ask new questions about how implicit biases relate to systemic racism. Connor and Evers (2020) critiqued the model, but their critique simply restates the core claims of the model. They agreed that implicit bias varies across individuals and across contexts; that it is unreliable and weakly associated with behavior at the individual level; and that aggregating scores to measure context-level effects makes them more stable and predictive of group-level outcomes. Connor and Evers concluded that implicit bias should be considered to really be noisily measured individual construct because the effects of aggregation are merely statistical. We respond to their specific arguments and then discuss what it means to really be a feature of persons versus situations, and multilevel measurement and theory in psychological science more broadly.

scholarly journals Examining the Effects of Three Group-Level Metacognitive Scaffoldings on In-Service Teachers’ Knowledge Building

2021 ◽  
pp. 073563312110308
Author(s):  
Fan Ouyang ◽  
Si Chen ◽  
Yuqin Yang ◽  
Yunqing Chen
Keyword(s):  
Small Groups ◽  
Mixed Method ◽  
Peer Interactions ◽  
Knowledge Building ◽  
Group Level ◽  
Question Asking ◽  
Individual Level ◽  
The Individual ◽  
Task Oriented ◽  
Metacognitive Scaffolding

Group-level metacognitive scaffolding is critical for productive knowledge building. However, previous research mainly focuses on the individual-level metacognitive scaffoldings in helping learners improve knowledge building, and little effort has been made to develop group-level metacognitive scaffolding (GMS) for knowledge building. This research designed three group-level metacognitive scaffoldings of general, task-oriented, and idea-oriented scaffoldings to facilitate in-service teachers’ knowledge building in small groups. A mixed method is used to examine the effects of the GMSs on groups’ knowledge building processes, performances, and perceptions. Results indicate a complication of the effects of GMSs on knowledge building. The idea-oriented scaffolding has potential to facilitate question-asking and perspective-proposing inquiry through peer interactions; the general scaffolding does not necessarily lessen teachers’ idea-centered explanation and elaboration on the individual level; the task-oriented scaffolding has the worst effect. Pedagogical and research implications are discussed to foster knowledge building with the support of GMSs.

scholarly journals Isolated individuals and groups show opposite preferences toward humidity

2018 ◽  
Author(s):  
Mariano Calvo Martín ◽  
Stamatios C. Nicolis ◽  
Isaac Planas-Sitjà ◽  
Jean-Christophe de Biseau ◽  
Jean-Louis Deneubourg
Keyword(s):  
Relative Humidity ◽  
Environmental Conditions ◽  
Group Level ◽  
Individual Level ◽  
Negative Effect ◽  
Multi Level ◽  
The Individual ◽  
Shed Light ◽  
Selection Of

AbstractCockroaches, like most social arthropods, are led to choose collectively among different alternative resting places. These decisions are modulated by different factors, such as environmental conditions (temperature, relative humidity) and sociality (groups size, nature of communications). The aim of this study is to establish the interplay between environmental conditions and the modulation of the interactions between individuals within a group leading to an inversion of preferences. We show that the preferences of isolated cockroaches and groups of 16 individuals, on the selection of the relative humidity of a shelter are inversed and shed light on the mechanisms involved. We suggest that the relative humidity has a multi-level influence on cockroaches, manifested as an attractant effect at the individual level and as a negative effect at the group level, modulating the interactions.

scholarly journals The Online Elicitation of Personal Utility Functions (OPUF) tool: a new method for valuing health states

2022 ◽  
Vol 7 ◽  
pp. 14
Author(s):  
Paul Schneider ◽  
Ben van Hout ◽  
Marike Heisen ◽  
John Brazier ◽  
Nancy Devlin
Keyword(s):  
Utility Functions ◽  
Health State ◽  
Group Level ◽  
Health States ◽  
Online Tool ◽  
Value Set ◽  
Individual Level ◽  
Personal Utility ◽  
Value Sets ◽  
The Individual

Introduction Standard valuation methods, such as TTO and DCE are inefficient. They require data from hundreds if not thousands of participants to generate value sets. Here, we present the Online elicitation of Personal Utility Functions (OPUF) tool; a new type of online survey for valuing EQ-5D-5L health states using more efficient, compositional elicitation methods, which even allow estimating value sets on the individual level. The aims of this study are to report on the development of the tool, and to test the feasibility of using it to obtain individual-level value sets for the EQ-5D-5L. Methods We applied an iterative design approach to adapt the PUF method, previously developed by Devlin et al., for use as a standalone online tool. Five rounds of qualitative interviews, and one quantitative pre-pilot were conducted to get feedback on the different tasks. After each round, the tool was refined and re-evaluated. The final version was piloted in a sample of 50 participants from the UK. A demo of the EQ-5D-5L OPUF survey is available at: https://eq5d5l.me Results On average, it took participants about seven minutes to complete the OPUF Tool. Based on the responses, we were able to construct a personal EQ-5D-5L value set for each of the 50 participants. These value sets predicted a participants' choices in a discrete choice experiment with an accuracy of 80%. Overall, the results revealed that health state preferences vary considerably on the individual-level. Nevertheless, we were able to estimate a group-level value set for all 50 participants with reasonable precision. Discussion We successfully piloted the OPUF Tool and showed that it can be used to derive a group-level as well as personal value sets for the EQ-5D-5L. Although the development of the online tool is still in an early stage, there are multiple potential avenues for further research.

scholarly journals Individual-Level and Population-Level Lateralization: Two Sides of the Same Coin

Symmetry ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 739 ◽  
Author(s):  
Elisa Frasnelli ◽  
Giorgio Vallortigara
Keyword(s):  
Evolutionarily Stable Strategy ◽  
Population Level ◽  
Point Of View ◽  
Theoretical Point ◽  
Evolutionarily Stable Strategies ◽  
Functional Roles ◽  
Individual Level ◽  
Social Species ◽  
The Individual ◽  
Evolutionarily Stable

Lateralization, i.e., the different functional roles played by the left and right sides of the brain, is expressed in two main ways: (1) in single individuals, regardless of a common direction (bias) in the population (aka individual-level lateralization); or (2) in single individuals and in the same direction in most of them, so that the population is biased (aka population-level lateralization). Indeed, lateralization often occurs at the population-level, with 60–90% of individuals showing the same direction (right or left) of bias, depending on species and tasks. It is usually maintained that lateralization can increase the brain’s efficiency. However, this may explain individual-level lateralization, but not population-level lateralization, for individual brain efficiency is unrelated to the direction of the asymmetry in other individuals. From a theoretical point of view, a possible explanation for population-level lateralization is that it may reflect an evolutionarily stable strategy (ESS) that can develop when individually asymmetrical organisms are under specific selective pressures to coordinate their behavior with that of other asymmetrical organisms. This prediction has been sometimes misunderstood as it is equated with the idea that population-level lateralization should only be present in social species. However, population-level asymmetries have been observed in aggressive and mating displays in so-called “solitary” insects, suggesting that engagement in specific inter-individual interactions rather than “sociality” per se may promote population-level lateralization. Here, we clarify that the nature of inter-individuals interaction can generate evolutionarily stable strategies of lateralization at the individual- or population-level, depending on ecological contexts, showing that individual-level and population-level lateralization should be considered as two aspects of the same continuum.

scholarly journals Counting Happiness from the Individual Level to the Group Level

2012 ◽  
Vol 114 (2) ◽  
pp. 621-637 ◽  
Author(s):  
Edsel L. Beja ◽  
David B. Yap
Keyword(s):  
Group Level ◽  
Individual Level ◽  
The Individual

scholarly journals Bearing the Weight of Imprisonment: The Relationship Between Prison Climate and Well-Being

2019 ◽  
Vol 46 (10) ◽  
pp. 1385-1404 ◽  
Author(s):  
Esther F. J. C. van Ginneken ◽  
Hanneke Palmen ◽  
Anouk Q. Bosma ◽  
Miranda Sentse
Keyword(s):  
The Netherlands ◽  
Multilevel Analysis ◽  
Well Being ◽  
Group Level ◽  
Individual Level ◽  
Unit Level ◽  
Positive Effects ◽  
Individual Perceptions ◽  
The Individual ◽  
The Relationship

Little is known about the relative influence of shared and individual perceptions of prison climate on adjustment to incarceration. This study investigated the relationship between prison climate and well-being among a sample of 4,538 adults incarcerated in the Netherlands. Prison climate dimensions were considered both as prison unit-level variables and as individual-level perceptions. Multilevel analysis results showed that most variance for well-being is found at the individual rather than the unit level. This implies that it does not make much of a difference for well-being in which prison unit someone resides. Positive effects of prison climate on well-being were primarily found for individual perceptions of prison climate, rather than for the aggregate unit measures. More research is needed to determine whether this finding holds true in other countries. The findings confirm the importance of disentangling the contribution of prison climate at the individual and group level.

scholarly journals Ain’t Too Proud to Beg! Effects of Leader’s Use of Pride on Groups

2020 ◽  
Vol 17 (19) ◽  
pp. 7146
Author(s):  
Catherine S. Daus ◽  
Stephen R. Baumgartner
Keyword(s):  
Emotional Labor ◽  
Emotion Management ◽  
Task Group ◽  
Group Level ◽  
Individual Level ◽  
Group Satisfaction ◽  
The Individual ◽  
The Impact ◽  
Authentic Pride ◽  
Generally True

Studies of discrete pride in the workplace are both few and on the rise. We examined what has, to date, been unstudied, namely the impact that a leader’s expressions of authentic and hubristic pride can have on the followers at that moment, and on their attitudes regarding their task, leader, and group. Students working in groups building Lego structures rated their perceived leader regarding expressions of pride, both authentic and hubristic. Students who perceived the leader as expressing more authentic pride rated the task, group (satisfaction and cohesion), and leader more positively, while the reverse was generally true for perceptions of expressions of hubristic pride. We found these effects both at the individual level and at the group level. We also predicted and found moderation for the type of task worked on, creative or detailed. Implications abound for leader emotional labor and emotion management.

Definiteness in written Swedish by Finnish-speaking immersion pupils at the end of immersion

2018 ◽  
Vol 6 (1) ◽  
pp. 57-84
Author(s):  
Eeva-Liisa Nyqvist
Keyword(s):  
Control Group ◽  
Group Level ◽  
Individual Level ◽  
Definite Form ◽  
Spontaneous Writing ◽  
Acquisition Order ◽  
The Individual ◽  
The Right ◽  
Better Than

Abstract There are two primary goals for this study – first, to analyse definiteness and article use in spontaneous writing in Swedish by 15-year-old Finnish immersion students (n = 162) and secondly, to compare their performance with that of non-immersion students at the same age (n = 67). Analyses at the group level show that immersion students usually perform significantly better than the control group, but they also reveal similar problems to what L2-Swedish non-immersion students have demonstrated in previous studies, such as omission of indefinite articles and difficulty in choosing the right definite form of the noun. Still, these inaccuracies occurred less often in the data from the immersion students. The studied constructions also show at the group level an acquisition order similar to that reported in previous studies, explainable by different aspects of complexity and cross-linguistic influence. Analyses on the individual level, however, show different acquisition orders depending on the criteria being used.

scholarly journals Vestibular contribution to balance control in the medial gastrocnemius and soleus

2016 ◽  
Vol 115 (3) ◽  
pp. 1289-1297 ◽  
Author(s):  
Christopher J. Dakin ◽  
Martin E. Héroux ◽  
Billy L. Luu ◽  
John Timothy Inglis ◽  
Jean-Sébastien Blouin
Keyword(s):  
Surface Electromyography ◽  
Balance Control ◽  
Motor Units ◽  
Vestibular Stimulation ◽  
Standing Balance ◽  
Medial Gastrocnemius ◽  
Functional Roles ◽  
Discharge Behavior ◽  
Balance Corrections ◽  
Biphasic Responses

The soleus (Sol) and medial gastrocnemius (mGas) muscles have different patterns of activity during standing balance and may have distinct functional roles. Using surface electromyography we previously observed larger responses to galvanic vestibular stimulation (GVS) in the mGas compared with the Sol muscle. However, it is unclear whether this difference is an artifact that reflects limitations associated with surface electromyography recordings or whether a compensatory balance response to a vestibular error signal activates the mGas to a greater extent than the Sol. In the present study, we compared the effect of GVS on the discharge behavior of 9 Sol and 21 mGas motor units from freely standing subjects. In both Sol and mGas motor units, vestibular stimulation induced biphasic responses in measures of discharge timing [11 ± 5.0 (mGas) and 5.6 ± 3.8 (Sol) counts relative to the sham (mean ± SD)], and frequency [0.86 ± 0.6 Hz (mGas), 0.34 ± 0.2 Hz (Sol) change relative to the sham]. Peak-to-trough response amplitudes were significantly larger in the mGas (62% in the probability-based measure and 160% in the frequency-based measure) compared with the Sol (multiple P < 0.05). Our results provide direct evidence that vestibular signals have a larger influence on the discharge activity of motor units in the mGas compared with the Sol. More tentatively, these results indicate the mGas plays a greater role in vestibular-driven balance corrections during standing balance.

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