The temporal dynamics of effect anticipation in course of action planning

“Strong” versions of the ideomotor theory of action control claim that anticipations of the environmental effects that actions bring about are mandatory for response selection. This is considered to be the one and only way of how actions can be voluntarily selected. We studied this notion in a series of four experiments where we adapted the flanker paradigm to investigate the involvement of effect codes in the preparation of motor responses. Participants first learned that their responses to stimulus letters were contingently followed by the presentation of a new letter on the screen. In the second phase of the experiments, the action-demanding letters were presented together with the effects of the correct response, effects of other responses, or neutral letters. Varying the stimulus onset asynchrony (SOA) between target stimuli and the flanking effect stimuli provides the opportunity to investigate the temporal dynamics of the activation of effect codes. Hence, flanker stimuli were presented before, simultaneously with, or after the onset of the target. The results indicate that effect-related information from the flanker stimuli is involved in the preparation process, but mainly in later phases of response preparation. The observed pattern of results suggests that, at least under conditions where responses are determined by stimuli, effect codes are activated in course of response planning to enable the evaluation of the executed response and the monitoring of response execution, but they do not automatically activate the responses themselves.     

Changes in grasping kinematics due to different start postures of the hand

It was proposed that grasping is a relatively stereotyped movement pattern which can be subdivided into the components of manipulation, transport, and orientation of the hand. However, it is still a matter of debate whether these components are independent of each other. In three experiments we altered the start posture of the hand by either changing the size of the start aperture or the orientation of the hand prior to movement onset. The variation of the aperture size primarily affected the manipulation component of the grip resulting in an overall change of the pre-shaping profile. In contrast, an alteration of the start orientation affected the manipulation and the transport components to a similar extent. These results give further evidence that hand orientation is neither planned nor controlled independently from the other movement components. Moreover, when the grip had to match specific object properties, adjustments were mainly achieved within the first movement part. In contrast, when there were no movement constraints the final finger positions were influenced by the initial start posture of the hand. We found no evidence for a fixed spatial or temporal coupling of the grasp and the transport component in our experiments.     

Movement adaptations in 7- to 10-year-old typically developing children: evidence for a transition in feedback-based motor control

We used a modified double-step pointing task to study movement adaptations in 7- to 10-year-old typically developing children. We found that the majority (63%) were able to optimally adapt fast, goal-directed visually-guided movements to a late change in target location meeting the requirements of speed and accuracy. A minority (35%) failed to meet the requirement of accuracy resulting in a less optimal adaptation. The results showed that the ability to adapt movements optimally develops before the age of 7 years in typically developing children. Literature proposes a transition in development of motor control around the age of 8 years. The present results replicate and extend this by suggesting that this transition affects the later phases of fast, goal-directed visually-guided movements rather than the early phases, such as movement programming and acceleration. Finally, the results indicate that the optimally adapted movements were the result of a specific strategy in which a specific component of movement execution was slowed on all trials. This suggests that 7- to 10-year-old typically developing children have developed implicit knowledge about which movement components are the most efficient to adapt.     

Factors contributing to the quality of the transition out of elite sports in Swiss,Danish, and Polish athletes

ObjectivesThe aim of this study was (a) to compare athletic retirement of former Swiss, Danish, and Polish athletes; and (b) to explore the influence of factors on the quality of the transition. Based on existing transitional models, we developed a working model to investigate the predictive power of commonly assumed resources and barriers related to the transition (Park, Lavallee, & Tod, 2013).Design and methodsFormer international elite athletes from Switzerland (n = 231), Denmark (n = 86), and Poland (n = 84) from 35 different sports completed an online questionnaire in their native language. Mean/proportional differences across countries were explored using ANOVAs and chi-square tests. For each sample, a multiple regression analysis was performed with 26 predictors on the transition quality, which was a component score of seven variables.Results and conclusionsMore differences were found among individual characteristics (e.g., educational level, athletic identity, confidence in skills), whereas athletes reported a similar pattern concerning retirement planning and voluntariness to end their career regardless of the context. The adaptation process following the career end was easiest for Swiss athletes and most difficult for Polish athletes. Results of the multiple regressions revealed both common resources (e.g., voluntariness) and barriers (e.g., athletic identity), but also factors that worked as resources in one context, but as barriers in another (e.g., high sportcareer income). We propose to avoid generalizations about resources and barriers influencing the transition, but to apply a culturally sensitive approach when studying athletic retirement in different contexts.