An examination of perceptual-motor recalibration in a 1-vs-1 anticipation test.

This study examined the processes of perceptual-motor calibration/recalibration of defensive football players in a 1-vs-1 scenario. Ankle weights were used to reduce the acceleration capabilities of players performing an anticipation test, with the aim being to examine the player's response to the disturbance in terms of when movement was initiated and the impact on the mechanisms that underpinned anticipation, namely gaze behaviour. The ankle weights disturbed the perceptual-motor system and players initiated movement significantly earlier in the 1-vs-1 anticipation test. Analyses of perceptual-motor calibration/recalibration revealed that players acted closer to their maximal action capabilities prior to the addition of ankle weights, which negatively influenced the scaling of action capabilities. Moreover, players were unable to recalibrate whilst wearing ankle weights. However, following the withdrawal of the ankle weights, players were able to recalibrate within 11-15 trials. Players did not adapt gaze behaviour as a result of the disturbance being placed on the perceptual-motor system, but task familiarization resulted in more efficient eye movements. The results of this study show the importance of providing players the opportunity to "scale" action to perceptual information.

Examining the effect of reduced action capabilities on defensive anticipation in a 1-vs-1 task.

This study used small-sided games (SSGs) to induce fatigue and therefore, reduce the action capabilities of Varsity soccer players (n= 20). The aim was to examine the effect of compromised action capabilities on defensive movement response in a 1-vs-1 scenario. Action capabilities were assessed via countermovement jumps (CMJ), 5-m acceleration, 20-m sprint and a Change of Direction (COD) test. Defensive movement response was measured via a Soccer-Specific Anticipation Test (SSAT). Following SSGs, significant reductions were observed in jump (p=.04, d=.31), acceleration (p<.001, d=.98), and sprint (p<.001, d=.66) performance. Significantly, players tended to move earlier in the SSAT following SSGs (p=.049, d=.66). Furthermore, to examine the distinct effect of reductions in each action capability, players were categorised according to whether SSGs had a worthwhile change in CMJ, acceleration, sprint or COD performance. For each of the four measures, movements tended to be initiated earlier following SSGs, although pre-/post-SSGs differences were not significant (p =.08-.51), moderate to large effect sizes were shown (d=.56-.84). These findings intimate that compromised action capabilities influence the timing of the movement response of defensive players in 1-vs-1 situations.

The combination of physical and mental load exacerbates the negative effect of each on the capability of skilled soccer players to anticipate action.

This study examined the impact of combining physical and mental load on the anticipatory judgements of skilled soccer players. Sixteen players completed an 11vs11 video anticipation test in four counterbalanced conditions, each separated by 7 days. The baseline condition consisted of only the anticipation test. A physical load condition required participants to complete a simulated soccer protocol on a treadmill followed by the anticipation test. A mental load condition required participants to complete a 30-min Stroop test followed by the anticipation test. Finally, in the combined load condition, participants completed the physical load protocol alongside the mentally loading Stroop task followed by the anticipation test. Response accuracy, visual search behaviour and measures of effort were assessed throughout. Response accuracy decreased in the separate physical load and mental load conditions when compared to baseline and worsened further in the combined load condition. The reduction in response accuracy across experimental conditions coincided with an increase in the number of fixations when compared to the baseline condition. It is suggested that the separate sources of load impaired the players ability to allocate sufficient resources to task-relevant information leading to a reduction in anticipatory accuracy, and this was exacerbated in the combined load condition.

The Effects of High- and Low-Anxiety Training on the Anticipation Judgments of Elite Performers.

We examined the effects of high- versus low-anxiety conditions during video-based training of anticipation judgments using international-level badminton players facing serves and the transfer to high-anxiety and field-based conditions. Players were assigned to a high-anxiety training (HA), low-anxiety training (LA) or control group (CON) in a pretraining-posttest design. In the pre- and posttest, players anticipated serves from video and on court under high- and low-anxiety conditions. In the video-based high-anxiety pretest, anticipation response accuracy was lower and final fixations shorter when compared with the low-anxiety pretest. In the low-anxiety posttest, HA and LA demonstrated greater accuracy of judgments and longer final fixations compared with pretest and CON. In the high-anxiety posttest, HA maintained accuracy when compared with the low-anxiety posttest, whereas LA had lower accuracy. In the on-court posttest, the training groups demonstrated greater accuracy of judgments compared with the pretest and CON.

The coupling between gaze behavior and opponent kinematics during anticipation of badminton shots.

PURPOSE: We examined links between the kinematics of an opponent's actions and the visual search behaviors of badminton players responding to those actions. METHOD: A kinematic analysis of international standard badminton players (n = 4) was undertaken as they completed a range of serves. Video of these players serving was used to create a life-size temporal occlusion test to measure anticipation responses. Expert (n = 8) and novice (n = 8) badminton players anticipated serve location while wearing an eye movement registration system. RESULTS: During the execution phase of the opponent's movement, the kinematic analysis showed between-shot differences in distance traveled and peak acceleration at the shoulder, elbow, wrist and racket. Experts were more accurate at responding to the serves compared to novice players. Expert players fixated on the kinematic locations that were most discriminating between serve types more frequently and for a longer duration compared to novice players. Moreover, players were generally more accurate at responding to serves when they fixated vision upon the discriminating arm and racket kinematics. CONCLUSIONS: Findings extend previous literature by providing empirical evidence that expert athletes' visual search behaviors and anticipatory responses are inextricably linked to the opponent action being observed.

Rearrangement of the ETS genes ETV-1, ETV-4, ETV-5, and ELK-4 is a clonal event during prostate cancer progression.

ETS gene rearrangements are frequently found in prostate cancer. Several studies have assessed the rearrangement status of the most commonly found ETS rearranged gene ERG, and the less frequent genes, ETV-1, ETV-4, ETV-5, and ELK-4 in primary prostate cancer. However, frequency in metastatic disease is not well investigated. Recently, we have assessed the ERG rearrangement status in both primary and corresponding lymph node metastases and observed that ERG rearrangement in primary prostate cancer transfers into lymph node metastases, suggesting it to be a clonal expansion event during prostate cancer progression. As a continuation, we investigated in this study whether this observation is valid for the less frequent ETS rearranged genes. Using dual-color break-apart fluorescent in situ hybridization assays, we evaluated the status of all less frequent ETS gene rearrangements for the first time on tissue microarrays constructed from a large cohort of 86 patients with prostate cancer and composed of primary and corresponding lymph node metastases, as well as in a second cohort composed of 43 distant metastases. ETV-1, ETV-4, ETV-5, and ELK-4 rearrangements were found in 8 (10%) of 81, 5 (6%) of 85, 1 (1%) of 85, and 2 (2%) of 86 of primary prostate cancer, respectively, and in 6 (8%) of 73, 4 (6%) of 72, 1 (1%) of 75, and 1 (1%) of 78 of corresponding lymph node metastases, respectively. ETV-1 and ETV-5 rearrangements were not found in the distant metastases cases, whereas ETV-4 and ELK-4 rearrangements were found in 1 (4%) of 25 and 1 (4%) of 24, respectively. Our findings suggest that rearrangement of the less frequent ETS genes is a clonal event during prostate cancer progression.

Digital arthrodesis: current fixation techniques.

Several hammertoe implant devices have recently been introduced in an attempt to provide optimal fixation for proximal interphalangeal joint arthrodesis. This article reviews these implants individually, and discusses their advantages and disadvantages. There is a lack of research with long-term follow-up available for these devices. Percutaneous Kirschner-wire fixation persists as a time-honored and effective method of fixation. The buried Kirschner-wire technique is also an effective, cost-conscious option, with many of the same advantages as newer implantable devices.