On discontinuities in motor learning: a longitudinal study of complex skill acquisition on a ski-simulator

The qualitative behavioral reorganizations that occurred during the acquisition of a complex motor skill were examined. Five novice participants practiced for 39 sessions of ten 1-min trials on a modified version of the ski-simulator. Analyses focused on the motion of the apparatus platform, modeled as a self-sustained oscillator. At the beginning of the experiment, all participants adopted a behavior that could be modeled with a highly nonlinear stiffness function and a Rayleigh damping function. The behavior in the final part of the experiment was captured by a qualitatively different model, with a linear stiffness function and a van der Pol damping behavior. The transition from the initial to the final model was gradual and was marked in most cases by an abrupt increase of oscillation frequency. During the transition stage, the 2 damping behaviors seemed alternately exploited within each trial. The results are discussed in the framework of the dynamical systems approach to motor coordination and learning, considering motor skill acquisition as a phase transition.     

ELF: A new measure of response capture

Response capture is a widespread and extensively studied phenomenon, in particular in decision tasks involving response conflict. Its intensity is routinely quantified by conditional accuracy function (CAF). We argue that this method might be misleading, and propose an alternative approach, the error location function (ELF). While CAF provides the error rate by bins of reaction time (RT), ELF represents the share of total errors below each quantile of RT. We derive from ELF an index of response capture, the error location index (ELI), which represents the area below the ELF. Using simulations of computational models, we show that ELF and ELI specifically quantify variations in response capture. Finally, we illustrate the usefulness of ELF and ELI through experimental data and show that ELF and CAF can yield to contradictory conclusions.     

The influence of gender,social roles,and facial appearance on perceived emotionality

One of the most pervasive gender stereotypes in Western culture concerns expectations regarding men's and women's emotionality. Whereas men are expected to be anger prone, women are expected to smile more. At the same time, men are generally perceived as more facially dominant and facially dominant individuals are expected to show more anger. That is, both facial appearance and social role expectations would lead observers to expect men to show more anger. The present research had the goal to disentangle the unique contribution of these two factors. As it is impossible in our society to fully untangle the influence of these factors since they are highly confounded, we created an alien society where these factors could be unconfounded. In this alien world, Deluvia, child rearing is exclusively assumed by a third gender, the caregiver, whereas men and women share the same social roles. The facial appearance of the Deluvians was varied along the dominance continuum. The results showed that facially dominant Deluvians, regardless of gender, were expected to show more anger, disgust, and contempt and less happiness, fear, sadness, and surprise. Also, the nurturing caregivers were expected to show less anger, contempt, and disgust as well as more fear, sadness, and surprise, regardless of facial appearance. No effect of gender per se on perceived emotionality was found. Copyright © 2009 John Wiley & Sons, Ltd.     

EFFECTIVENESS OF FUNCTIONAL COMMUNICATION TRAINING WITH AND WITHOUT EXTINCTION AND PUNISHMENT: A SUMMARY OF 21 INPATIENT CASES

Functional communication training (FCT) is a frequently used treatment for reducing problem behavior exhibited by individuals with developmental disabilities. Once the operant function of problem behavior is identified by a functional analysis, the client is taught to emit an appropriate communicative response to obtain the reinforcer that is responsible for behavioral maintenance. Studies on FCT have typically used small numbers of participants, have reported primarily on clients for whom FCT was successful, and have varied with respect to their use of other treatment components. The main purposes of the present study were to evaluate the efficacy of FCT for treating severe problem behavior in a relatively large sample of individuals with mental retardation (N = 21) and to determine the contribution of extinction and punishment components to FCT treatment packages. FCT with extinction was effective in reducing problem behavior for the majority of clients and resulted in at least a 90% reduction in problem behavior in nearly half the applications. However, when demand or delay-to-reinforcement fading was added to FCT with extinction, treatment efficacy was reduced in about one half of the applications. FCT with punishment (both with and without fading) resulted in at least a 90% reduction in problem behavior for every case in which it was applied.     

Quality of Life in Patients with Recurrent Vasovagal or Unexplained Syncope: Influence of Sex, Syncope Type and Illness Representations

Health-related quality of life (QoL) is reduced in patients with recurrent vasovagal (VVS) or unexplained (US) syncope. Little is known regarding these patients’ QoL as pertains to their capacity to attain their life goals. Factors influencing QoL, such as sex, syncope type and illness representations have not been studied. Our objective is to examine the relationship between illness representations and QoL, as well as possible sex and syncope type differences. One hundred and four patients undergoing tilt-table testing (TTT) for recurrent syncope were interviewed one month before TTT, using questionnaires. Data were analysed using ANCOVAs, a-priori Helmert contrasts for illness representations, and regressions. Patients with US had a poor QoL compared to those with VVS [F(1, 91) = 10.46; p < 0.01], particularly in men (p < 0.01). Patients with higher perceived syncope severity showed an impoverished QoL relative to those with less severe perceptions [F(1, 91) = 5.47; p < 0.05]. A hierarchical regression revealed that illness representations mediate the impact of lifetime number of syncope on QoL. In conclusion, QoL is reduced in these patients, and is influenced by illness representations. Helping patients change their perceptions about their syncope may be an efficient way to promote QoL.     

A methodological note on nonlinear time series analysis: is the open- and closed-loop model of Collins and De Luca (1993) a statistical artifact?

The authors reexamined, theoretically and empirically, the method proposed by J. J. Collins and C. D. De Luca (1993) for the analysis of center-of-pressure trajectories. The main argument in this article is that Collins and De Luca's approach is not adapted to the analysis of bounded time series and leads to statistical artifacts such as underestimation of the diffusion process for long-term intervals. The open- and closed-loop model developed by Collins and De Luca is a direct consequence of those statistical problems. Applying more classical methods, such as rescaled range analysis or detrended fluctuation analysis, the authors show that center-of-pressure trajectories can be modeled as continuous, antipersistent fractional Brownian motion. More specifically, those trajectories behave like 1/f noise, a ubiquitous feature in adaptive biological systems.     

An enhanced experimental procedure to rationalize on the impairment of perception of action capabilities

It is well documented that changes in the physiological states of the perceiver–actor influence the perception of action capabilities. However, because experimental procedures of most studies involved a limitless availability for stimuli visual encoding and perceptual strategies, it remains difficult to adopt a single position among the large range of alternative interpretations for impaired perception. A reaching-to-grasp paradigm under breathing restriction was adapted from Graydon et al. (Cogn Emot 26:1301–1305, 2012) to standardize the time for encoding of stimuli information and narrowed the involvement of perceptual strategies. In the present study, we propose a highly controlled environment where the discrete information is presented during 300 ms, congruently with neurophysiological studies focused on visuomotor transformation. An underestimation of the perception of action capabilities is found under breath restriction, suggesting that 300 ms for stimuli encoding is sufficient to induce altered visuomotor brain transformations when limiting the involvement of perceptual strategies. This result suggests that such behavior could refer to an impaired brain potentiation of the perceptual occurrence, providing strong hypotheses on the brain dynamics of sensorimotor integration that underlie impaired perception of action capabilities in stressful situations.     

Does the transcranial direct current stimulation improve dual-task postural control in young healthy adults?

Cognitive Processing - Some studies have suggested that postural balance improved after a single session of transcranial direct current stimulation (tDCS), whereas others have found minimal, if...     

Gender differences in romantic relationship memories: who remembers? Who cares?

Two studies were conducted to assess patterns of gender differences in memory for romantic relationship events. Results suggested that people believe that women have better memory for romantic relationship events than men, that better relationship memory predicts higher levels of relationship well-being, and that the association between relationship memory and relationship well-being is somewhat stronger for women than for men. Women did tend to have somewhat better relationship memory than men, as assessed via subjective reports from both partners in mixed-sex relationships, and via the number of details partners provided when asked to recall a specific relationship event (i.e., their first date). Consistent with the lay theories, both own and partner’s better relationship memory predicted higher levels of relationship well-being; however, the association between better relationship memory and higher levels of relationship well-being was equally strong for both genders. Implications and future research directions are discussed.     

The effect of group-identification on emotion recognition: The case of cats and basketball players

It has been suggested that the in-group advantage in the recognition of emotional expressions by members of different cultural groups may be due to either encoder differences in expressive style or to decoder biases. The latter may be explained by the fact that individuals who identify with an ethnic or social group exert more effort when trying to decode the emotional expressions of group members. The present study investigates this notion. For this, two target groups were chosen such that in-group and out-group members shared the same cultural knowledge and linguistic background and all participants rated the same expressions to control for encoder differences. Both studies showed that individuals who identified with a social group were better at recognizing expressions by individuals perceived as members of that group.