Molecular Mechanisms Associated with the Benefits of Variable Practice in Motor Learning

Abstract

Variable practice promotes a higher level of motor learning than constant practice. The glutamate receptors, n-methyl-d-aspartate (NMDA) and alfa-amino-3-hydroxy-5-methyl-4-isoxazolepropionic (AMPA), have been associated with the changes in motor cortex that occur throughout the process of motor learning. Considering that, it is possible that variable practice is more associated with the NMDA and AMPA receptors than constant practice. This study aimed ao investigating the association between the glutamate receptors, NMDA and AMPA, and constant and variable practice schedules. Seventy-eight male mice practiced the rotarod task in a constant or variable scheduling, in two consecutive days (acquisition phase). Learning tests were performed 24?h and 10?days after the end of the acquisition phase. Variable practice was more associated with the NMDA receptor and had a greater AMPA receptor expression than constant practice. The results suggest that the benefits of variable practice are result of both the greater dependency on the NMDA receptor and the greater AMPA receptor expression.     

Effects of Different Ratios of Physical and Mental Practice on Postural Control Improvement

Abstract

Mental practice (MP) is a reliable alternative or complement to physical practice (PP) for the training of postural control. We address how MP should ideally be combined with PP. Participants were assigned to four experimental groups where MP/PP ratios during training varied from 0 to 100%. Performance improved only for demanding postural adjustments, regardless of MP/PP ratio, and learning was partially consolidated after a night of sleep. Findings reinforce the relevance of MP for the training of weight shifting and further suggest that MP alone can be as efficient as PP for the learning of certain complex postural adjustments.     

The many facets of speech production and its complex effects on phonological processing

In our commentary, we discuss two additional points about developmental speech production. First, we suggest that more precision is needed to accurately describe ‘speech production’ processes, and we suggest that hierarchical constructs from the adult literatures on articulatory phonology and speech motor control may be applicable to infants as well. Second, we discuss the implications from data that indicate that the effects of production are subject to task‐, attentional‐, linguistic‐, and experience‐related demands.     

Explaining social contagion in sport applying Heider's balance theory: First experimental results

A sudden collective collapse of an entire sport team is often described in terms of the social contagion of weak performance. Two experiments studied this phenomenon against the backdrop of balance theory. Experiment 1 examined whether false negative feedback on a partner's performance during a team task would lead to compensatory mechanisms as predicted by balance theory. Results showed that perceived negative performance in the partner was compensated by devaluing the relationship to the partner. Experiment 2 replicated Experiment 1 and investigated the impact of physical self-esteem. Results showed that persons with strong physical self-esteem devalued the situational value of the relationship when they perceived their partner's performance to be negative. Experiment 2 also investigated objective performance. Although failing to attain statistical significance, there was a tendency for the perceived sudden decline in the partner's performance to be contagious. It is concluded that balance theory offers promising insights into the interpersonal dynamics of social contagion.     

Step by step: A microgenetic study of the development of strategy choice in infancy

To examine patterns of strategy choice and discovery during problem‐solving of a novel locomotor task, 13.5‐ and 18‐month‐old infants were placed at the top of a staircase and encouraged to descend. Spontaneous stair descent strategy choices were documented step by step and trial by trial to provide a microgenetic account of problem‐solving in action. Younger infants tended to begin each trial walking, were more likely to choose walking with each successive step, and were more likely to lose their balance and have to be rescued by an experimenter. Conversely, older infants tended to begin each trial scooting, were more likely to choose scooting with each successive step, and were more likely to use a handrail to augment balance on stairs. Documenting problem‐solving microgenetically across age groups revealed striking similarities between younger infants' strategy development and older children's behaviour on more traditionally cognitive tasks, including using alternative strategies, mapping prior experiences with strategies to a novel task, and strengthening new strategies. As cognitive resources are taxed during a challenging task, resources available for weighing alternatives or inhibiting a well‐used strategy are reduced. With increased motor experience, infants can more easily consider alternative strategies and maintain those solutions over the course of the trial.     

How contextual and individual characteristics influence psychological needs satisfaction: The critical roles of political skill and political will

This two-study research package investigates the interactive effects of perceptions of organizational politics, political skill, and political will on psychological need satisfaction, which has been shown to predict a number of different important organizational outcomes. Drawing primarily on social/political influence and self-determination theories, we propose that although perceptions of organizational politics (i.e., as an important situational or contextual variable) can demonstrate need-thwarting effects for some, its effects can be need-satisfying for those individuals with high levels of political skill and political will. In Study 1, we analyze a sample of 142 individuals to demonstrate that possessing political skill attenuates the negative effects of perceptions of organizational politics on psychological need satisfaction. In Study 2, we analyze a sample of 420 individuals to demonstrate that respondents with high levels of both political skill and political will experience their highest levels of need satisfaction in highly political environments. Theoretical contributions, limitations and future research directions, and practical implications are discussed.     

Longer,smaller, faster,stronger: On skills and intelligence

ABSTRACT

How does practice change our behaviors such that they go from being awkward, unskilled actions to elegant, skilled performances? This is the question that I wish to explore in this paper. In the first section of the paper, I will defend the tight connection between practice and skill and then go on to make precise how we ought to construe the concept of practice. In the second section, I will suggest that practice contributes to skill by structuring and automatizing the motor routines constitutive of skilled actions. I will cite how this fact about skilled action has misled many philosophers to conclude that skills are mindless or bodily. In the third section of the paper, I will challenge this common misconception about automaticity by appealing to empirical evidence of motor chunking. This evidence reveals that there are two opposing processes involved in the automaticity of skilled action: one process that is largely associative, which I will call “concatenation,” and a second which is a controlled cognitive process, which I will call “segmentation.” As a result of this evidence, we will be in a position to see clearly why skills are minded and intelligent not merely during their acquisition and not simply in virtue of their connection to intentional states but, rather, in their very nature. I will end by reflecting on some theoretical reasons for why this is exactly what we should expect to be the case when it comes to skilled action.