TY - JOUR A1 - Schaefer, Laura A1 - Bittmann, Frank T1 - Are there two forms of isometric muscle action? BT - Results of the experimental study support a distinction between a holding and a pushing isometric muscle function JF - BMC sports science, medicine & rehabilitation N2 - Background In isometric muscle function, there are subjectively two different modes of performance: one can either hold isometrically – thus resist an impacting force – or push isometrically – therefore work against a stable resistance. The purpose of this study is to investigate whether or not two different isometric muscle actions – the holding vs. pushing one (HIMA vs PIMA) – can be distinguished by objective parameters. Methods Ten subjects performed two different measuring modes at 80% of MVC realized by a special pneumatic system. During HIMA the subject had to resist the defined impacting force of the pneumatic system in an isometric position, whereby the force of the cylinder works in direction of elbow flexion against the subject. During PIMA the subject worked isometrically in direction of elbow extension against a stable position of the system. The signals of pressure, force, acceleration and mechanomyography/-tendography (MMG/MTG) of the elbow extensor (MMGtri/MTGtri) and the abdominal muscle (MMGobl) were recorded and evaluated concerning the duration of maintaining the force level (force endurance) and the characteristics of MMG-/MTG-signals. Statistical group differences comparing HIMA vs. PIMA were estimated using SPSS. Results Significant differences between HIMA and PIMA were especially apparent regarding the force endurance: During HIMA the subjects showed a decisively shorter time of stable isometric position (19 ± 8 s) in comparison with PIMA (41 ± 24 s; p = .005). In addition, during PIMA the longest isometric plateau amounted to 59.4% of the overall duration time of isometric measuring, during HIMA it lasted 31.6% (p = .000). The frequency of MMG/MTG did not show significant differences. The power in the frequency ranges of 8–15 Hz and 10–29 Hz was significantly higher in the MTGtri performing HIMA compared to PIMA (but not for the MMGs). The amplitude of MMG/MTG did not show any significant difference considering the whole measurement. However, looking only at the last 10% of duration time (exhaustion), the MMGtri showed significantly higher amplitudes during PIMA. Conclusion The results suggest that under holding isometric conditions muscles exhaust earlier. That means that there are probably two forms of isometric muscle action. We hypothesize two potential reasons for faster yielding during HIMA: (1) earlier metabolic fatigue of the muscle fibers and (2) the complexity of neural control strategies. KW - Two forms of isometric muscle action KW - Holding isometric muscle action KW - Pushing isometric muscle action KW - Mechanomyography KW - Mechanotendography Y1 - 2017 U6 - https://doi.org/10.1186/s13102-017-0075-z VL - 9 PB - BioMed Central CY - London ER - TY - JOUR A1 - Schaefer, Laura A1 - Hoff, Marco A1 - Bittmann, Frank T1 - Measuring system and method of determining the Adaptive Force JF - European journal of translational myology N2 - The term Adaptive Force (AF) describes the capability of adaptation of the nerve-muscle-system to externally applied forces during isometric and eccentric muscle action. This ability plays an important role in real life motions as well as in sports. The focus of this paper is on the specific measurement method of this neuromuscular action, which can be seen as innovative. A measuring system based on the use of compressed air was constructed and evaluated for this neuromuscular function. It depends on the physical conditions of the subject, at which force level it deviates from the quasi isometric position and merges into eccentric muscle action. The device enables – in contrast to the isokinetic systems – a measure of strength without forced motion. Evaluation of the scientific quality criteria of the devices was done by measurements regarding the intra- and interrater-, the test-retest-reliability and fatiguing measurements. Comparisons of the pneumatic device with a dynamometer were also done. Looking at the mechanical evaluation, the results show a high level of consistency (r²=0.94 to 0.96). The parallel test reliability delivers a very high and significant correlation (ρ=0.976; p=0.000). Including the biological system, the concordance of three different raters is very high (p=0.001, Cronbachs alpha α=0.987). The test retest with 4 subjects over five weeks speaks for the reliability of the device in showing no statistically significant differences. These evaluations indicate that the scientific evaluation criteria are fulfilled. The specific feature of this system is that an isometric position can be maintained while the externally impacting force rises. Moreover, the device can capture concentric, static and eccentric strength values. Fields of application are performance diagnostics in sports and medicine. KW - Adaptive Force KW - isometric eccentric force KW - muscle action KW - motor control KW - strength measurement system Y1 - 2017 U6 - https://doi.org/10.4081/ejtm.2017.6479 SN - 2037-7460 VL - 27 IS - 3 SP - 152 EP - 159 PB - Unipress CY - Padova ER - TY - JOUR A1 - Scheepers, Christoph A1 - Mohr, Sibylle A1 - Fischer, Martin H. A1 - Roberts, Andrew M. T1 - Listening to Limericks - A Pupillometry Investigation of Perceivers' Expectancy JF - PLoS one N2 - What features of a poem make it captivating, and which cognitive mechanisms are sensitive to these features? We addressed these questions experimentally by measuring pupillary responses of 40 participants who listened to a series of Limericks. The Limericks ended with either a semantic, syntactic, rhyme or metric violation. Compared to a control condition without violations, only the rhyme violation condition induced a reliable pupillary response. An anomaly-rating study on the same stimuli showed that all violations were reliably detectable relative to the control condition, but the anomaly induced by rhyme violations was perceived as most severe. Together, our data suggest that rhyme violations in Limericks may induce an emotional response beyond mere anomaly detection. Y1 - 2013 U6 - https://doi.org/10.1371/journal.pone.0074986 SN - 1932-6203 VL - 8 IS - 9 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Schwarzenthal, Miriam A1 - Juang, Linda P. A1 - Schachner, Maja Katharina A1 - van de Vijver, Fons J. R. T1 - A multimodal measure of cultural intelligence for adolescents growing up in culturally diverse societies JF - International Journal of Intercultural Relations N2 - Adolescents growing up in culturally diverse societies need to develop intercultural competence. To better understand how to develop intercultural competence we need measures specifically relating to the everyday intercultural experiences of adolescents. However, few measures of intercultural competence are available for this target group. Based on the cultural intelligence (CQ) model (Earley & Ang, 2003), we developed a measure that combines a self-report questionnaire and situational judgment tests (SJTs). The latter comprise a brief description of intercultural situations, followed by questions asking the adolescents to interpret and provide a reaction to the situations. The reliability, factor structure, measurement equivalence, and validity of the new measure was tested in two samples of adolescents in culturally diverse regions in North Rhine-Westphalia (N = 631, 48% female, M-a(ge) = 13.69 years, SDage = 1.83) and Berlin (N = 1,335, 48% female, M-age = 14.69 years, SDage, = 0.74) in Germany. The self-report CQ scale showed good reliability and a four-dimensional factor structure with a higher-order CQ factor. The responses to the SJTs were coded based on a coding manual and the ratings loaded onto one factor. The measurement models showed metric to scalar measurement equivalence across immigrant background, gender, and grade. The CQ factor and the SJT factor were positively correlated with each other, as well as with related constructs such as openness, perspective-taking, and diversity beliefs. We conclude that the new measure offers a reliable and valid method to assess the intercultural competence of adolescents growing up in culturally diverse societies. KW - Cultural intelligence KW - Intercultural competence KW - Adolescents Y1 - 2019 U6 - https://doi.org/10.1016/j.ijintrel.2019.07.007 SN - 0147-1767 SN - 1873-7552 VL - 72 SP - 109 EP - 121 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Sellaro, Roberta A1 - Dolk, Thomas A1 - Colzato, Lorenza S. A1 - Liepelt, Roman A1 - Hommel, Bernhard T1 - Referential Coding Does Not Rely on Location Features: Evidence for a Nonspatial Joint Simon Effect JF - Journal of experimental psychology : Human perception and performance N2 - The joint Simon effect (JSE) shows that the presence of another agent can change one's representation of one's task and/or action. According to the spatial response coding approach, this is because another person in one's peri-personal space automatically induces the spatial coding of one's own action, which in turn invites spatial stimulus-response priming. According to the referential coding approach, the presence of another person or event creates response conflict, which the actor is assumed to solve by emphasizing response features that discriminate between one's own response and that of the other. The 2 approaches often make the same predictions, but the spatial response coding approach considers spatial location as the only dimension that can drive response coding, whereas the referential coding approach allows for other dimensions as well. To compare these approaches, the authors ran 2 experiments to see whether a nonspatial JSE can be demonstrated. Participants responded to the geometrical shape of a central colored stimulus by pressing a left or right button, while wearing gloves of the same or different color as the stimuli. Participants performed the task individually, either by responding to either stimulus shapes (Experiment 1) or by responding to only 1 of the 2 shapes (Experiment 2), and in the presence of a coactor. Congruence between stimulus and glove color affected performance in the 2-choice and the joint tasks but not in the individual go/no-go task. This demonstration of a nonspatial JSE is inconsistent with the spatial response coding approach but supports the referential coding approach. KW - joint Simon effect KW - referential coding KW - spatial response coding KW - dimensional overlap KW - compatibility effect Y1 - 2015 U6 - https://doi.org/10.1037/a0038548 SN - 0096-1523 SN - 1939-1277 VL - 41 IS - 1 SP - 186 EP - 195 PB - American Psychological Association CY - Washington ER - TY - JOUR A1 - Shaki, Samuel A1 - Fischer, Martin H. T1 - Competing Biases in Mental Arithmetic BT - When Division Is More and Multiplication Is Less JF - Frontiers in human neuroscience N2 - Mental arithmetic exhibits various biases. Among those is a tendency to overestimate addition and to underestimate subtraction outcomes. Does such “operational momentum” (OM) also affect multiplication and division? Twenty-six adults produced lines whose lengths corresponded to the correct outcomes of multiplication and division problems shown in symbolic format. We found a reliable tendency to over-estimate division outcomes, i.e., reverse OM. We suggest that anchoring on the first operand (a tendency to use this number as a reference for further quantitative reasoning) contributes to cognitive biases in mental arithmetic. KW - heuristics and biases KW - numerical cognition KW - mental arithmetic KW - mental number line KW - operational momentum Y1 - 2017 U6 - https://doi.org/10.3389/fnhum.2017.00037 SN - 1662-5161 VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Sidiropoulos, Kyriakos A1 - De Bleser, Ria A1 - Ablinger, Irene A1 - Ackermann, Hermann T1 - The relationship between verbal and nonverbal auditory signal processing in conduction aphasia: behavioral and anatomical evidence for common decoding mechanisms JF - Neurocase : the neural basis of cognition N2 - The processing of nonverbal auditory stimuli has not yet been sufficiently investigated in patients with aphasia. On the basis of a duration discrimination task, we examined whether patients with left-sided cerebrovascular lesions were able to perceive time differences in the scale of approximately 150ms. Further linguistic and memory-related tasks were used to characterize more exactly the relationships in the performances between auditory nonverbal task and selective linguistic or mnemonic disturbances. All examined conduction aphasics showed increased thresholds in the duration discrimination task. The low thresholds on this task were in a strong correlative relation to the reduced performances in repetition and working memory task. This was interpreted as an indication of a pronounced disturbance in integrating auditory verbal information into a long-term window (sampling disturbance) resulting in an additional load of working memory. In order to determine the lesion topography of patients with sampling disturbances, the anatomical and psychophysical data were correlated on the basis of a voxelwise statistical approach. It was found that tissue damage extending through the insula, the posterior superior temporal gyrus, and the supramarginal gyrus causes impairments in sequencing of time-sensitive information. KW - brain lesions KW - conduction aphasia KW - processing of auditory nonverbal stimuli KW - speech perception KW - speech pathology KW - lesion studies Y1 - 2015 U6 - https://doi.org/10.1080/13554794.2014.902471 SN - 1355-4794 SN - 1465-3656 VL - 21 IS - 3 SP - 377 EP - 393 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Sixtus, Elena A1 - Fischer, Martin H. T1 - Eine kognitionswissenschaftliche Betrachtung der Konzepte "Raum" und "Zahl" JF - Raum und Zahl im Fokus der Wissenschaften : eine multidisziplinäre Vorlesungsreihe Y1 - 2015 SN - 978-3-86464-082-7 SP - 35 EP - 62 PB - Trafo CY - Berlin ER - TY - JOUR A1 - Slimani, Maamer A1 - Paravlic, Armin A1 - Granacher, Urs T1 - A Meta-Analysis to Determine Strength Training Related Dose-Response Relationships for Lower-Limb Muscle Power Development in Young Athletes JF - Frontiers in Physiology N2 - It is well-documented that strength training (ST) improves measures of muscle strength in young athletes. Less is known on transfer effects of ST on proxies of muscle power and the underlying dose-response relationships. The objectives of this meta-analysis were to quantify the effects of ST on lower limb muscle power in young athletes and to provide dose-response relationships for ST modalities such as frequency, intensity, and volume. A systematic literature search of electronic databases identified 895 records. Studies were eligible for inclusion if (i) healthy trained children (girls aged 6–11 y, boys aged 6–13 y) or adolescents (girls aged 12–18 y, boys aged 14–18 y) were examined, (ii) ST was compared with an active control, and (iii) at least one proxy of muscle power [squat jump (SJ) and countermovement jump height (CMJ)] was reported. Weighted mean standardized mean differences (SMDwm) between subjects were calculated. Based on the findings from 15 statistically aggregated studies, ST produced significant but small effects on CMJ height (SMDwm = 0.65; 95% CI 0.34–0.96) and moderate effects on SJ height (SMDwm = 0.80; 95% CI 0.23–1.37). The sub-analyses revealed that the moderating variable expertise level (CMJ height: p = 0.06; SJ height: N/A) did not significantly influence ST-related effects on proxies of muscle power. “Age” and “sex” moderated ST effects on SJ (p = 0.005) and CMJ height (p = 0.03), respectively. With regard to the dose-response relationships, findings from the meta-regression showed that none of the included training modalities predicted ST effects on CMJ height. For SJ height, the meta-regression indicated that the training modality “training duration” significantly predicted the observed gains (p = 0.02), with longer training durations (>8 weeks) showing larger improvements. This meta-analysis clearly proved the general effectiveness of ST on lower-limb muscle power in young athletes, irrespective of the moderating variables. Dose-response analyses revealed that longer training durations (>8 weeks) are more effective to improve SJ height. No such training modalities were found for CMJ height. Thus, there appear to be other training modalities besides the ones that were included in our analyses that may have an effect on SJ and particularly CMJ height. ST monitoring through rating of perceived exertion, movement velocity or force-velocity profile could be promising monitoring tools for lower-limb muscle power development in young athletes. KW - resistance training KW - muscle fitness KW - youth KW - meta-analysis KW - jump performance Y1 - 2018 U6 - https://doi.org/10.3389/fphys.2018.01155 SN - 1664-042X VL - 9 SP - 1 EP - 14 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Stelzel, Christine A1 - Schauenburg, Gesche A1 - Rapp, Michael A. A1 - Heinzel, Stephan A1 - Granacher, Urs T1 - Age-Related Interference between the Selection of Input-Output Modality Mappings and Postural Control BT - a Pilot Study JF - Frontiers in psychology N2 - Age-related decline in executive functions and postural control due to degenerative processes in the central nervous system have been related to increased fall-risk in old age. Many studies have shown cognitive-postural dual-task interference in old adults, but research on the role of specific executive functions in this context has just begun. In this study, we addressed the question whether postural control is impaired depending on the coordination of concurrent response-selection processes related to the compatibility of input and output modality mappings as compared to impairments related to working-memory load in the comparison of cognitive dual and single tasks. Specifically, we measured total center of pressure (CoP) displacements in healthy female participants aged 19–30 and 66–84 years while they performed different versions of a spatial one-back working memory task during semi-tandem stance on an unstable surface (i.e., balance pad) while standing on a force plate. The specific working-memory tasks comprised: (i) modality compatible single tasks (i.e., visual-manual or auditory-vocal tasks), (ii) modality compatible dual tasks (i.e., visual-manual and auditory-vocal tasks), (iii) modality incompatible single tasks (i.e., visual-vocal or auditory-manual tasks), and (iv) modality incompatible dual tasks (i.e., visual-vocal and auditory-manual tasks). In addition, participants performed the same tasks while sitting. As expected from previous research, old adults showed generally impaired performance under high working-memory load (i.e., dual vs. single one-back task). In addition, modality compatibility affected one-back performance in dual-task but not in single-task conditions with strikingly pronounced impairments in old adults. Notably, the modality incompatible dual task also resulted in a selective increase in total CoP displacements compared to the modality compatible dual task in the old but not in the young participants. These results suggest that in addition to effects of working-memory load, processes related to simultaneously overcoming special linkages between input- and output modalities interfere with postural control in old but not in young female adults. Our preliminary data provide further evidence for the involvement of cognitive control processes in postural tasks. KW - cognitive-postural dual task KW - postural stability KW - working memory KW - modality compatibility KW - aging Y1 - 2017 U6 - https://doi.org/10.3389/fpsyg.2017.00613 SN - 1664-1078 VL - 8 PB - Frontiers Research Foundation CY - Lausanne ER -