Perceptual load in sport and the heuristic value of the perceptual load paradigm in examining expertise-related perceptual-cognitive adaptations

In two experiments, we transferred perceptual load theory to the dynamic field of team sports and tested the predictions derived from the theory using a novel task and stimuli. We tested a group of college students (N = 33) and a group of expert team sport players (N = 32) on a general perceptual load task and a complex, soccer-specific perceptual load task in order to extend the understanding of the applicability of perceptual load theory and further investigate whether distractor interference may differ between the groups, as the sport-specific processing task may not exhaust the processing capacity of the expert participants. In both, the general and the specific task, the pattern of results supported perceptual load theory and demonstrates that the predictions of the theory also transfer to more complex, unstructured situations. Further, perceptual load was the only determinant of distractor processing, as we neither found expertise effects in the general perceptual load task nor the sport-specific task. We discuss the heuristic utility of using response-competition paradigms for studying both general and domain-specific perceptual-cognitive adaptations.     

Brain correlates of subjective freedom of choice

The subjective feeling of free choice is an important feature of human experience. Experimental tasks have typically studied free choice by contrasting free and instructed selection of response alternatives. These tasks have been criticised, and it remains unclear how they relate to the subjective feeling of freely choosing. We replicated previous findings of the fMRI correlates of free choice, defined objectively. We introduced a novel task in which participants could experience and report a graded sense of free choice. BOLD responses for conditions subjectively experienced as free identified a postcentral area distinct from the areas typically considered to be involved in free action. Thus, the brain correlates of subjective feeling of free action were not directly related to any established brain correlates of objectively-defined free action. Our results call into question traditional assumptions about the relation between subjective experience of choosing and activity in the brain’s so-called voluntary motor areas.     

Effect of a Defining Feature on Negative Priming Across the Life Span

Negative priming paradigms examine selective attention, and may be explained by inhibitory processes (e.g. Tipper, 1985). Our study examines inhibition in children (6-11 years), younger adults (18-22 years), and older adults (60-82 years). Younger adults show inhibition to the reported feature of a stimulus (location or identity) (Milliken, Tipper, & Weaver, 1994) and to the defining feature of a stimulus (identity or colour) (Simone, Carlisle, & McCormick, 1998). Neither children (Tipper, Bourque, Anderson, & Brehaut, 1989) nor older adults (Connelly & Hasher, 1993) have consistently shown significant inhibition to the reported feature of identity, suggesting developmentally impaired inhibitory processing. Our current study demonstrates that both inhibition of a defining feature of identity and a reported feature of location are stable across the life span.     

Differential effects of a visual illusion on online visual guidance in a stable environment and online adjustments to perturbations

In the reported, experiment participants hit a ball to aim at the vertex of a Müller–Lyer configuration. This configuration either remained stable, changed its shaft length or the orientation of the tails during movement execution. A significant illusion bias was observed in all perturbation conditions, but not in the stationary condition. The illusion bias emerged for perturbations shortly after movement onset and for perturbations during execution, the latter of which allowed only a minimum of time for making adjustments (i.e., approx.170 ms). These findings indicate that allocentric information is exploited for online control when people make rapid adjustments in response to a sudden change in the environment and not when people guide their limb movements to interact with a stable environment.     

Delayed auditory feedback and movement

It is well known that timing of rhythm production is disrupted by delayed auditory feedback (DAF), and that disruption varies with delay length. We tested the hypothesis that disruption depends on the state of the movement trajectory at the onset of DAF. Participants tapped isochronous rhythms at a rate specified by a metronome while hearing DAF (for piano tones) of differing lengths. Motion capture was used to analyze movement trajectories. Mean Inter-Response Intervals (IRIs) varied as an approximately sinusoidal function of feedback condition, with DAF causing slowed production for shorter delays and speeded production for faster delays. Motion capture analyses revealed that finger velocity at the time of DAF predicted the effect of DAF on mean IRI whereas finger position predicted the variability of IRIs. A second experiment in which participants were instructed to vary the timing of peak finger height confirmed that the effect of DAF on timing variability is directly influenced by the finger trajectory.     

Can the onset of type 2 diabetes be delayed by a group-based lifestyle intervention? A randomised control trial

This study was a randomised control trial with a waiting control group. It was designed to evaluate the effectiveness of a 6-month, group-based diabetes prevention programme, The Healthy Living Course and assess whether participation in the programme led to changes in modifiable risk factors for type 2 diabetes among an already at-risk pre-diabetic population. Individuals designated at risk for diabetes by their general practitioners (GPs) were screened using an Oral Glucose Tolerance Test. Volunteers (N = 307) with pre-diabetes were assigned to an intervention or wait-control group in the ratio of approximately 2 : 1. The sample was pre-tested on biochemical, anthropometric and self-report behavioural, cognitive and mood variables and post-tested either at the end of the educational/support-based lifestyle programme or the end of the wait period. The intervention group significantly improved their diabetes knowledge, motivation to change, positive affect, healthy eating and activity levels and showed significantly greater reductions in weight, body mass index, waist circumference, diastolic blood pressure and fasting plasma glucose in comparison with controls. The intervention group also changed their diagnostic status from pre-diabetes to non-diabetes at a greater rate than the wait group (43% vs. 26%) who received standard care from their GPs.     

Resilience and successful community reintegration among female forensic psychiatric patients: a preliminary investigation

Research on resiliency and recovery in forensic psychiatric patients is still limited. Information pertaining to factors associated with successful community reintegration would contribute to a more comprehensive assessment of functioning and informed treatment planning that fits within a recovery approach of service provision. Using a retrospective design involving file reviews and a 3-year follow-up period, the authors investigated the rate of successful/unsuccessful community reintegration (defined by the presence or absence of an absolute discharge/readmission to hospital) in female forensic psychiatric patients (N = 48). The study evaluated the extent to which the risk and protective factors captured in the Short-Term Assessment of Risk and Treatability (START) predicted a range of positive and negative outcomes in the study sample. Results showed that 47.9% of the women qualified as having successfully reintegrated into the community, with the remaining 52.1% qualifying as still being in recovery. Successful individuals possessed significantly more protective factors and significantly fewer risk factors than individuals still in recovery. Furthermore, both the vulnerability and the strength scale of the START demonstrated good predictive validity, however we did not find evidence of incremental validity of the strength scale. Copyright © 2011 John Wiley & Sons, Ltd.     

Representing others' actions: the role of expertise in the aging mind

A large body of evidence suggests that action execution and action observation share a common representational domain. To date, little is known about age-related changes in these action representations that are assumed to support various abilities such as the prediction of observed actions. The purpose of the present study was to investigate (a) how age affects the ability to predict the time course of observed actions; and (b) whether and to what extent sensorimotor expertise attenuates age-related declines in prediction performance. In a first experiment, older adults predicted the time course of familiar everyday actions less precisely than younger adults. In a second experiment, younger and older figure skating experts as well as age-matched novices were asked to predict the time course of figure skating elements and simple movement exercises. Both young age and sensorimotor expertise had a positive influence on prediction performance of figure skating elements. The expertise-related benefit did not show a transfer to movement exercises. Together, the results suggest a specific decline of action representations in the aging mind. However, extensive sensorimotor experience seems to enable experts to represent actions from their domain of expertise more precisely even in older age.