Visual search strategies of experienced and nonexperienced swimming coaches

The aim of this study consists of the application of an experimental protocol that allows information to be obtained about the visual search strategies elaborated by swimming coaches. 16 swimming coaches participated. The Experienced group (n=8) had 16.1 yr. (SD=8.2) of coaching experience and at least five years of experience in underwater vision. The Nonexperienced group in underwater vision (n= 8) had 4.2 yr. (SD= 4.0) of coaching experience. Participants were tested in a laboratory environment using a video-projected sample of the crawl stroke of an elite swimmer. This work discusses the main areas of the swimmer's body used by coaches to identify and analyse errors in technique from overhead and underwater perspectives. In front-underwater videos, body roll and mid-water were the locations of the display with higher percentages of fixation time. In the side-underwater slow videos, the upper body was the location with higher percentages of visual fixation time and was used to detect the low elbow fault. Side-overhead takes were not the best perspectives to pick up information directly about performance of the arms; coaches attended to the head as a reference for their visual search. The observation and technical analysis of the hands and arms were facilitated by an underwater perspective. Visual fixation on the elbow served as a reference to identify errors in the upper body. The side-underwater perspective may be an adequate way to identify correct knee angles in leg kicking and the alignment of a swimmer's body and leg actions.     

A model of involvement in work-related learning and development activity: the effects of individual,situational, motivational,and age variables

Eight hundred employees from across the U.S. work force participated in a detailed 13-month longitudinal study of involvement in learning and development activities. A new model was posited and tested in which the hypothesized sequence was as follows: worker age --> individual and situational antecedents --> perceived benefits of participation and self-efficacy for development --> attitudes toward development --> intentions to participate --> participation. The results depict a person who is oriented toward employee development as having participated in development activities before, perceiving themselves as possessing qualities needed for learning, having social support for development at work and outside of work, being job involved, having insight into his or her career, and believing in the need for development, in his or her ability to develop skills and to receive intrinsic benefits from participating. Given the aging work force, a detailed treatment of age differences in development is presented. Implications for new ideas in practice and future research are discussed.     

Contextual interference in learning precision skills

This research studied the effect of different organisations of practice (blocked and random) on the learning of three different types of throwing. 35 male students practiced three precise throws for 3 wk. Initially the subjects were separated into two groups who trained under different conditions of practice (blocked and random). All subjects improved significantly from initial performance, with both blocked practice and random practice. At the end of acquisition no differences were found between the groups. No significant differences were found on retention tests carried out 48 hr., 4 wk., and 8 wk. after the training period.     

Effects of acute, repeated and chronic variable stress on in vivo tyrosine hydroxylase activity and on alpha(2)-adrenoceptor sensitivity in the rat brain

We assessed the effects of a single tail pinch and two chronic stress regimes, repeated and variable, on in vivo tyrosine hydroxylase activity and on alpha2-adrenoceptor sensitivity in two brain regions. After administering a 3,4-dihydroxyphenylalanine (DOPA) decarboxylase inhibitor, tyrosine hydroxylase activity, measured as the accumulation of DOPA, and noradrenaline (NA) content were determined by using high-performance liquid chromatography. A single tail pinch for 5 min induced an enhancement of DOPA content in hippocampus (28%) and hypothalamus (67%) which was still present 24 h later. This increase could account for the lack of changes in NA content in both regions after the application of this stressor. However, tyrosine hydroxylase activity was unmodified 24 h after exposure to both repeated (5 min of tail pinch, twice daily, for 14 days) and chronic variable stress (one of 5 different stressors, once daily, for 14 days) although there was an enhancement of NA levels in hippocampus (45 and 54%, respectively) and hypothalamus (24.5 and 36%, respectively). The sensitivity of the alpha2-adrenoceptors which regulate [3H]-NA release in hippocampal and hypothalamic synaptosomes was not modified by the acute or chronic stress protocols assayed. The results show that both paradigms of chronic stress had similar effects on the noradrenergic indices evaluated.     

Alexithymia--state or trait?

Alexithymia refers to a specific disturbance in emotional processing that is manifested by difficulties in identifying and verbalizing feelings and a tendency to focus on and amplify the somatic sensations that accompany emotional arousal. Alexithymia is conceptualized both as an affect-deficit disorder and a continuous personality variable. The main purpose of the present study was to investigate the stability levels of alexithymia with regard to changes in emotional distress levels caused by university exams. We tested 20 university students at four different times, before and after the exams. Alexithymic features and self-reported emotional distress (trait anxiety and physical symptoms) were measured. Whereas emotional distress measures changed significantly during the diverse phases, the level of alexithymia remained unchanged. We therefore conclude that alexithymia represents a constant trait.     

Differential efficacy of a cognitive-behavioral intervention versus pharmacological treatment in the management of fibromyalgic syndrome

Given that studies about the differential efficacy of existing treatments in fibromyalgia syndrome are scarce, the aim of this study was to compare the differential efficacy of a cognitive-behavioral and a pharmacological therapy on fibromyalgia. Using a randomized controlled clinical trial, 28 fibromyalgic patients were assigned to one of following experimental conditions: (a) pharmacological treatment (i.e., cyclobenzaprine), (b) cognitive-behavioral intervention (i.e., stress inoculation training), (c) combined pharmacological and cognitive-behavioral treatment and (d) no treatment. The results show the superiority of cognitive-behavioral intervention to reduce the severity of fibromyalgia both at the end of the treatment and at follow-up. We conclude that cognitive-behavioral interventions must be considered a primary treatment of fibromyalgia syndrome.     

Germs and angels: the role of testimony in young children's ontology

In three experiments, children's reliance on other people's testimony as compared to their own, first-hand experience was assessed in the domain of ontology. Children ranging from 4 to 8 years were asked to judge whether five different types of entity exist: real entities (e.g. cats, trees) whose existence is evident to everyone; scientific entities (e.g. germs, oxygen) that are normally invisible but whose existence is generally presupposed in everyday discourse; endorsed beings (e.g. the Tooth Fairy, Santa Claus) whose existence is typically endorsed in discourse with young children; equivocal beings (e.g. monsters, witches) whose existence is not typically endorsed in discourse with young children; and impossible entities (e.g. flying pigs, barking cats) that nobody believes in. Children make a broad dichotomy between entities and beings that they claim to exist (real entities; scientific entities; and endorsed beings) and those whose existence they deny (equivocal beings and impossible entities). They also make a more fine-grained distinction among the invisible entities that they claim to exist. Thus, they assert the existence of scientific entities such as germs with more confidence than that of endorsed beings such as Santa Claus. The findings confirm that children's ontological claims extend beyond their first-hand encounters with instances of a given category. Children readily believe in entities that they cannot see for themselves but have been told about. Their confidence in the existence of those entities appears to vary with the pattern of testimony that they receive.     

Visual and tactile guidance of dexterous manipulation tasks: an fMRI study

Models of motor guidance that dynamically adjust to the availability and quality of sensory information are based on the observation that dexterous tasks are routinely performed using various combinations of visual and tactile inputs. However, a dynamic neural system that acquires and processes relevant visual and tactile information remains relatively uncharacterized in humans. In this study, whole-brain functional magnetic resonance images were acquired during a dexterous manipulation task, compression of the end caps of a slender spring prone to buckling, to investigate the neural systems associated with motor guidance under four visual and tactile guidance conditions: (1) eyes closed (no visual input), smooth end caps, (2) eyes dosed, rough end caps, (3) eyes open and watching hand, smooth end caps, and (4) eyes open and watching hand, rough end caps. Performance of the dexterous task remained constant in all conditions. Variations in the two levels of visual input resulted in modulation of activity in the middle and inferior occipital gyrii and inferior parietal lobule, and variation in the two levels of tactile input during the task resulted in modulation of activity in the precentral (primary motor) gyrus. Although significantly active in all conditions, cingulate gyrus, medial frontal gyrus, postcentral gyrus, and cerebellum activities were not modulated by levels of either visual or somatosensory input, and no interaction effects were observed. Together, these data indicate that a fine-tuned motor task guided by varying visual and tactile information engages a distributed and integrated neural complex consisting of control and executive functions and regions that process dynamic sensory information related to guidance functions.     

Visual behavior and perception of trajectories of moving objects with visual occlusion

Experienced athletes in sports with moving objects have shown greater skill when using visual information to anticipate the direction of a moving object than nonexperienced athletes of those sports. Studies have shown that expert athletes are more effective than novices in occlusion situations in the first stages of the sports sequence. In this study, 12 athletes with different competitive experience in sports with moving objects viewed a sequence of tennis ball launches with and without visual occlusion, launched by a ball-shooting machine toward different areas with respect to the participant's position. The relation among visual behavior, occlusion time, and the precision of the task is reviewed. The spot where the balls bounced was analysed by a digital camera and visual behavior by an Eye Tracking System. Analysis showed that the nonexperienced athletes made significantly more errors and were more variable in visual occlusion conditions. Participants had a stable visual search strategy.