INT,ERDISCIPlINARY ANALYSIS OF BIOMECHANICAL MOVEMENT PATTERNS AND MENTAL REPRESENTATIONS OF THE VOLLEYBALL SPIKE

An approach for an integrative analysis of biomechanic and psychologic data is presented. Kinematic movement patterns as well as mental representation of the spike of male volleyball players have been studied to analyze structural interrelationships of cognitive and biomechanical measures. A high congruence of the results of cognitive and biomechanical analysis can be stated. Future research will focus on adaptations of mental representation and performance following practical and mental training, respectively

A Simple Model to Estimate the Percentage of Motor Plan Reuse From Hysteresis Effect Size

In sequential tasks, a partial reuse of former motor plans results in a persistence in the former posture (termed hysteresis). The cost-optimization hypothesis states that the percentage of reuse depends on the relative cognitive and mechanical cost of each movement. These costs should be constant across all drawers, yet previous studies found a larger hysteresis effect at the central drawers and declining effects toward the periphery. In the current study, we show that a simple mathematical model that assumes a sigmoid optimal grasp angle function and a fixed percentage of motor plan reuse explains the posture variance in a randomized and an ordered sequential drawer opening task. This finding indicates that (1) the optimal pro/supination angle is a sigmoid function of drawer height, (2) the percentage of motor plan reuse is constant across drawers, and (3) a constant percentage of reuse results in a larger hysteresis effect at the central drawers. Based on the model, the percentage of motor plan reuse in future studies can be estimated from the size of the motor hysteresis effect

A Simple Model to Estimate the Percentage of Motor Plan Reuse From Hysteresis Effect Size

In sequential tasks, a partial reuse of former motor plans results in a persistence in the former posture (termed hysteresis). The cost-optimization hypothesis states that the percentage of reuse depends on the relative cognitive and mechanical cost of each movement. These costs should be constant across all drawers, yet previous studies found a larger hysteresis effect at the central drawers and declining effects toward the periphery. In the current study, we show that a simple mathematical model that assumes a sigmoid optimal grasp angle function and a fixed percentage of motor plan reuse explains the posture variance in a randomized and an ordered sequential drawer opening task. This finding indicates that (1) the optimal pro/supination angle is a sigmoid function of drawer height, (2) the percentage of motor plan reuse is constant across drawers, and (3) a constant percentage of reuse results in a larger hysteresis effect at the central drawers. Based on the model, the percentage of motor plan reuse in future studies can be estimated from the size of the motor hysteresis effect

An Embodied Tutoring System for Literal vs. Metaphorical Concepts

In this paper we combine motion captured data with linguistic notions (preliminary study) in a game-like tutoring system (study 1), in order to help elementary school students to better differentiate literal from metaphorical uses of motion verbs, based on embodied information. In addition to the thematic goal, we intend to improve young students’ attention and spatiotemporal memory, by presenting sensorimotor data experimentally collected from thirty two participants in our motion capturing labs. Furthermore, we examine the accomplishment of tutor’s goals and compare them to curriculum’s approach (study 2). Sixty nine elementary school students were randomly divided in two experimental groups (game-like and traditional) and one control group, which did not undergo an intervention. All groups were tested in pre and post-tests. Even though the diagnostic pretests present a uniform picture, two way analysis of variance suggests that the experimental groups showed progress in post-tests and, more specifically, game-like group showed less wrong answers in the linguistics task and higher learning achievements compared to the other two groups. Furthermore, in the game-like condition the participants needed gradually shorter period of time to identify the avatar’s actions. This finding was considered as a first indication of attentional and spatiotemporal memory’s improvement, while the tutor’s assistance features cultivated students’ metacognitive perception

Simulating My Own or Others Action Plans? – Motor Representations, Not Visual Representations Are Recalled in Motor Memory

Seegelke C, Hughes CML, Schack T. Simulating My Own or Others Action Plans? – Motor Representations, Not Visual Representations Are Recalled in Motor Memory. PLoS ONE. 2013;8(12): e84662.Action plans are not generated from scratch for each movement, but features of recently generated plans are recalled for subsequent movements. This study investigated whether the observation of an action is sufficient to trigger plan recall processes. Participant dyads performed an object manipulation task in which one participant transported a plunger from an outer platform to a center platform of different heights (first move). Subsequently, either the same (intra-individual task condition) or the other participant (inter-individual task condition) returned the plunger to the outer platform (return moves). Grasp heights were inversely related to center target height and similar irrespective of direction (first vs. return move) and task condition (intra- vs. inter-individual). Moreover, participants' return move grasp heights were highly correlated with their own, but not with their partners' first move grasp heights. Our findings provide evidence that a simulated action plan resembles a plan of how the observer would execute that action (based on a motor representation) rather than a plan of the actually observed action (based on a visual representation)

Then and now: investigating anthropometrics and child mortality among females in Malawi

Information on the concentration of body mass index and child death among females in Malawi, where the epidemics of weight gain have been disconcerting and preventable deaths among children linger, is limited. Therefore, the study examined the polarity of body mass index and the death of children among females. Using data from the Malawian Demographic and Health Survey from 2000 to 2015–2016, the study applied for the first time the index of concentration at the extremes and indirect demographic techniques to estimate the polarity of body mass index and child mortality among 65,499 females aged 15 to 49 years. The preponderance of obesity more than doubled from 2000 to 2015–2016 and was highest among females who were older (35–49 years), urban dwellers, rich, and located in districts within the central and southern regions. In addition, child survival was low among underweight, overweight, and obese females. While national-, regional-, and individual-level statistics are in development, these findings provide helpful information for health experts and other stakeholders to initiate appropriate age-region specific programs and interventions in Malawi, including targeting females in the high socio-economic bracket

Manual (a)symmetries in grasp posture planning: a short review

Seegelke C, Hughes CML, Schack T. Manual (a)symmetries in grasp posture planning: a short review. Frontiers in Psychology. 2014;5:1480.Many activities of daily living require that we physically interact with one or more objects. Object manipulation provides an intriguing domain in which the presence and extent of manual asymmetries can be studied on a motor planning and a motor execution level. In this literature review we present a state of the art for manual asymmetries at the level of motor planning during object manipulation. First, we introduce pioneering work on grasp posture planning. We then sketch the studies investigating the impact of future task demands during unimanual and bimanual object manipulation tasks in healthy adult populations. In sum, in contrast to motor execution, there is little evidence for hand-based performance differences in grasp posture planning. We discuss potential reasons for the lack of manual asymmetries in motor planning and outline potential avenues of future research