Extended practice of reciprocal wrist and arm movements of varying difficulties

An experiment was designed to determine the degree to which reciprocal aiming movements of the wrist and arm with various accuracy requirements (Fitts' tasks) are enhanced by extended practice. The vast majority of research on motor learning shows performance improvement over practice. However, literature examining the effect of practice on Fitts' task performance is limited and inconclusive. Participants were asked to flex/extend their limb/lever in the horizontal plane at the wrist (arm stabilized) or elbow joint (wrist stabilized) in an attempt to move back and forth between two targets as quickly and accurately as possible. The targets and current position of the limb were projected on the screen in front of the participant. Target width was manipulated with amplitude constant (16°) in order to create indexes of difficulty (ID) of 1.5, 3, 4.5, and 6. Contrary to the earlier reports, after 20 days of practice, we found minimal changes in movement time or the movement time-ID relationships for the arm and wrist over practice. However, the variability in the movement endpoints decreased over practice and wrist movements at ID=6 were characterized by shorter movement times and longer dwell times relative to arm movements with dwell time for the wrist increasing over practice. These data are consistent with the notion that Fitts' tasks provide a stable measure of perceptual-motor capabilities.     

Neural dynamics of object-based multifocal visual spatial attention and priming: object cueing, useful-field-of-view, and crowding

How are spatial and object attention coordinated to achieve rapid object learning and recognition during eye movement search? How do prefrontal priming and parietal spatial mechanisms interact to determine the reaction time costs of intra-object attention shifts, inter-object attention shifts, and shifts between visible objects and covertly cued locations? What factors underlie individual differences in the timing and frequency of such attentional shifts? How do transient and sustained spatial attentional mechanisms work and interact? How can volition, mediated via the basal ganglia, influence the span of spatial attention? A neural model is developed of how spatial attention in the where cortical stream coordinates view-invariant object category learning in the what cortical stream under free viewing conditions. The model simulates psychological data about the dynamics of covert attention priming and switching requiring multifocal attention without eye movements. The model predicts how “attentional shrouds” are formed when surface representations in cortical area V4 resonate with spatial attention in posterior parietal cortex (PPC) and prefrontal cortex (PFC), while shrouds compete among themselves for dominance. Winning shrouds support invariant object category learning, and active surface-shroud resonances support conscious surface perception and recognition. Attentive competition between multiple objects and cues simulates reaction-time data from the two-object cueing paradigm. The relative strength of sustained surface-driven and fast-transient motion-driven spatial attention controls individual differences in reaction time for invalid cues. Competition between surface-driven attentional shrouds controls individual differences in detection rate of peripheral targets in useful-field-of-view tasks. The model proposes how the strength of competition can be mediated, though learning or momentary changes in volition, by the basal ganglia. A new explanation of crowding shows how the cortical magnification factor, among other variables, can cause multiple object surfaces to share a single surface-shroud resonance, thereby preventing recognition of the individual objects.     

Social skills, friendship and happiness: a cross-cultural investigation

The present study investigated the associations between social skills, friendship quality, and happiness, and tested a mediational model positing that friendship quality would mediate the relationship between social skills and happiness among American and Malaysian college students. Although American students reported significantly higher levels of psychosocial well-being than Malaysian students, the study variables were positively associated with each other in both cultures. More importantly, findings supported the proposed model in both groups. Results suggest that part of the reason why social skills are associated with positive psychological well-being is because of friendship experiences. Overall, the findings of the present study reinforce, extend and cross-culturally generalize the presumed benefits of social skills in positive well-being elaborated by Segrin and Taylor (2007). The authors also provided suggestions for future research.     

Perceptions of driver distraction among teenage drivers

Teenage drivers have been shown to have some of the highest crash risks. Crash data provide some insights on factors related to crash likelihood, but rarely capture all issues that can arise from driver distraction. The goal of this study was to assess teenage drivers’ opinions and perceptions of driver distraction. A survey of 1893 Iowa teenagers was conducted to determine and compare the frequency of engagement in distracting activities while driving to their opinions of what they actually consider to be distractions. A cluster analysis was conducted based on their indicated engagement in distracting activities with three groups emerging and classified as INFREQUENT, MODERATE, and FREQUENT engagers. Across all cluster groups, the majority (over 80%) indicated that they considered text messaging to be a distracting task. However, those clustered as FREQUENT engagers still reported a high level of texting while driving even though they considered this task to be distracting. A binary logistic regression model (adjusted for miles driven and license type) showed that FREQUENT and MODERATE engagers were more likely to be involved in a crash when compared to INFREQUENT engagers. The study demonstrates that not all teenagers place themselves at risk. There are subgroups of teenage drivers that often engage in activities they know are distracting, potentially putting themselves in danger. However, this is not the case for all teenage drivers and it is important to target interventions appropriately as well as foster a culture of safety both in schools and at home.     

Arrested development? Reconsidering dual-systems models of brain function in adolescence and disorders

The dual-systems model of a ventral affective system, whose reactivity confers risks and liabilities, and a prefrontal control system, whose regulatory capacities buffer against these vulnerabilities, is an intuitive account that pervades many fields in the cognitive neurosciences--especially in the study of populations that differ from neurotypical adults, such as adolescents or individuals with affective or impulse regulation disorders. However, recent evidence that is inconsistent with dual-systems models illustrates the complexity of developmental and clinical variations in brain function. Building new models to account for this complexity is critical to progress in these fields, and will be facilitated by research that emphasizes network-based approaches and maps relationships between structure and function, as well as brain and behavior, over time.     

Adolescent athletes’ learning about coping and the roles of parents and coaches

Objectives

The purpose of this study was to develop a grounded theory of the ways adolescent athletes learned about coping in sport. We subsequently came to focus on the roles of parents and coaches within this process.

Method

Interviews were conducted with 17 athletes (8 females, 9 males, M_age = 15.6 years), 10 parents (6 mothers, 4 fathers), and 7 male coaches. Grounded theory methodology (Corbin & Strauss, 2008) was used.

Results

Learning about coping was an experiential process consisting of the athletes’ sport experiences and learning through trial and error, reflective practice, and coping outcomes (consistent performance, independence in coping, and persistence in coping). Learning was facilitated by athletes being exposed to multiple situations and reflecting on their coping efforts. Parents and coaches helped athletes learn about coping by creating a supportive context for learning (listening and monitoring their own reactions, establishing trust and respect, reading the athlete, and fostering independence). Parents and coaches also used specific strategies to help athletes learn about coping, including questioning and reminding, providing perspective, sharing experiences, dosing stress experiences, initiating informal conversations, creating learning opportunities, and direct instruction.

Conclusions

Adolescent athletes must gain personal experience in dealing with stressors in order to learn how to cope. Parents and coaches represent key sources of influence within the process of learning about coping.