Bound by Experience: Updating the Body Representation When Using Virtual Objects.

OBJECTIVE: Four web-based experiments investigated flexibility of disembodiment of a virtual object that is no longer actively controlled. Emphasis was on possibilities to modify the timescale of this process. BACKGROUND: Interactions with virtual objects are commonplace in settings like teleoperation, rehabilitation, and computer-aided design. These objects are quickly integrated into the operator's body schema (embodiment). Less is known about how long such embodiment lasts. Understanding the dynamics of this process is crucial because different applied settings either profit from fast or slow disembodiment. METHOD: To induce embodiment, participants moved a 2D virtual hand through operating a computer mouse or touchpad. After initial embodiment, participants either stopped or continued moving for a fixed period of time. Embodiment ratings were collected continuously during each trial. RESULTS: Results across all experiments indicated that embodiment for the virtual hand gradually increased during active use and gradually decreased after stopping to use it. Disembodiment unfolded nearly twice as fast as embodiment and showed a curved decay pattern. These dynamics remained unaffected by anticipation of active control that would be required in an upcoming task. CONCLUSION: The results highlight the importance of continuously experiencing active control in virtual interactions if aiming at inducing stable embodiment of a virtual object. APPLICATION: Our findings suggest that applications of virtual disembodiment such as virtual tools or interventions to affect a person's body representation critically depend on continuous updating of sensorimotor experience. However, if switching between virtual objects, for example, during teleoperation or video gaming, after-effects are unlikely to affect performance.

Effects of prism adaptation and visual scanning training on perceptual and response bias in unilateral spatial neglect.

In some patients with unilateral spatial neglect, symptoms reflect impaired lateralized spatial attention and representation (perceptual bias) whereas in others the inability to respond to stimuli located in contralesional space (response bias). Here, we investigated whether prismatic adaptation (PA) and visual scanning training (VST) differentially affect perceptual and response bias and whether rehabilitation outcome depends on the type of bias underlying symptoms. Two groups of neglect patients in the subacute phase were evaluated before, immediately after, and two weeks following 10 days of PA (n = 9) or VST (n = 9). Standard neuropsychological tests (i.e., Behavioural Inattentional Test, Diller cancellation test, and Line Bisection test) were administered to assess neglect symptoms, while the Landmark task was used to disentangle perceptual and response biases. Performance on the Landmark task revealed that PA was more effective in improving the perceptual bias, while VST mainly modulated the response bias. Neuropsychological tests performance suggested that VST is better suited to modulate neglect in patients with response bias, while PA may be effective in patients with both types of bias. These findings may offer novel insights into the efficacy of PA and VST in the rehabilitation of perceptual and response biases in patients with neglect.

Influence of pilates training on physical coordination and stability of volleyball players / Influência do treinamento de pilates na coordenação física e estabilidade dos jogadores de voleibol / Influencia del entrenamiento de pilates en la coordinación física y en la estabilidad de los jugadores de voleibol

ABSTRACT Introduction: Pilates prioritizes the control of central muscle groups, which have a strong predilection value for volleyball training. Objective: To investigate the repercussions of Pilates training on motor coordination and stability in volleyball players. Methods: 20 athletes from a female volleyball team were randomly divided between the experimental and the control groups. Pilates intervention was performed in the experimental group. The control group followed the traditional training format, finally comparing the training results after eight weeks. Results: In the flexibility index of the experimental group, the weights increased from 23,11±5,08 times to 28,02±6,42 times; the left and right axes increased from 7,74±10,13 seconds to 8,83±8,13 seconds. In terms of the stability index, the number of intervals repeated in 20 seconds increased from 35.44±0.75 to 46.45±0.91; the lateral throw of the medicine ball was increased from 59.61±16.16 meters to 78.38±16.22 meters. The range of variation of each index is more evident than that of the control group. Conclusion: Pilates training becomes superior to usual training for the improvement of coordination and stability of volleyball players. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: O Pilates prioriza o controle de grupos musculares centrais, que possuem um forte valor prediletivo para o treinamento do vôlei. Objetivo: Investigar as repercussões do treino Pilates na coordenação motora e na estabilidade das jogadoras de voleibol. Métodos: 20 atletas de uma equipe feminina de voleibol foram divididas aleatoriamente entre o grupo experimental e o grupo controle. A intervenção do Pilates foi realizada no grupo experimental. O grupo de controle obedeceu ao formato tradicional de treinamento, comparando-se finalmente os resultados do treinamento após 8 semanas. Resultados: No índice de flexibilidade do grupo experimental, os pesos elevaram-se de 23.112 ± 5.088 vezes para 28.020 ± 6.427 vezes; os eixos esquerdo e direito cresceram de 7.745 ± 10.138 segundos para 8.831 ± 8.133 segundos. Em termos de índice de estabilidade, o número de intervalos repetidos em 20 segundos aumentou de 35.444 ± 0.753 para 46.453 ± 0.919; o arremesso lateral da bola medicinal foi elevado de 59.617 ± 16.160 metros para 78.386 ± 16.221 metros. O intervalo de variação de cada índice é mais evidente do que o do grupo de controle. Conclusão: O treinamento de Pilates se torna superior ao treinamento habitual para a melhora da coordenação e estabilidade das jogadoras de vôlei. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: Pilates prioriza el control de los grupos musculares centrales, que tienen un fuerte valor de predilección para el entrenamiento del voleibol. Objetivo: Investigar la repercusión del entrenamiento de Pilates sobre la coordinación motora y la estabilidad de jugadoras de voleibol. Métodos: 20 atletas de un equipo femenino de voleibol se dividieron aleatoriamente entre el grupo experimental y el grupo de control. La intervención de Pilates se realizó en el grupo experimental. El grupo de control siguió el formato de entrenamiento tradicional, comparando finalmente los resultados del entrenamiento después de 8 semanas. Resultados: En el índice de flexibilidad del grupo experimental, los pesos aumentaron de 23,11±5,08 veces a 28,02±6,42 veces; los ejes izquierdo y derecho aumentaron de 7,74±10,13 segundos a 8,83±8,13 segundos. En cuanto al índice de estabilidad, el número de intervalos repetidos en 20 segundos aumentó de 35,44±0,75 a 46,45±0,91; el lanzamiento lateral del balón medicinal aumentó de 59,61±16,16 metros a 78,38±16,22 metros. El rango de variación de cada índice es más evidente que el del grupo de control. Conclusión: El entrenamiento con Pilates llega a ser superior al entrenamiento habitual para la mejora de la coordinación y estabilidad de los jugadores de voleibol. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Response Preparation Affects Cognitive Motor Control.

OBJECTIVE: We investigated how the ability to control whether or not to inhibit an action is affected by the response preparation. BACKGROUND: The ability to control actions is a central skill to properly behave in complex environments. Increased levels of response preparation are associated with reduced response times, but how they directly affect the ability to control actions is not well explored. We investigated how the response preparation affects the ability to control the generation of actions in the context of a stop selective task. METHOD: Participants performed a visuo-motor stop selective task. RESULTS: We found that an increased level of response preparation reduced the ability to control actions. In the condition with high preparation, we observed shorter response times and increased probability of wrong responses to a request to stop, compared to a condition with a lower level of preparation. CONCLUSION: We demonstrated that high response preparation hinders action control. APPLICATION: Understanding the cognitive factors that affect the ability to properly control actions is crucial to develop devices that can be exploited in different contexts such as the aviation, industrial, and military. We demonstrated that subjects' response preparation is a key factor influencing their ability to flexibly control their reaction to different stimuli. This study offers a suitable paradigm that can be used to investigate which system features in a controlled task promote an optimal balance between response speed and error rate.

Efeitos da prática de artes marciais na aptidão física e características comportamentais de pessoas com deficiência intelectual: uma revisão sistemática / Efectos de la práctica de artes marciales en la aptitud física y las características de comportamiento de personas con discapacidad intelectual: una revisión sistemática / Effects of martial arts practice on physical fitness and behavioral characteristics of people with intellectual disabilities: a systematic review

Introdução: Pessoas com deficiência intelectual (DI) normalmente apresentam limitações no campo da interação social, e também podem ser acometidos por doenças crônicas. A atividade física e o esporte exercem importantes reduções nos riscos de desenvolver doenças, contudo, algumas modalidades ainda carecem de informação sobre sua efetividade, tais quais as artes marciais.Objetivo: Apresentar os efeitos relacionados a prática de artes marciais para pessoas com deficiência intelectual.Método: Uma busca sistemática em seis bases de dados foi realizada por dois avaliadores independentes. Os estudos deveriam trazer informações claras sobre o público com deficiência intelectual estudado além das características que compunham as intervenções selecionadas. A qualidade dos estudos foi avaliada pela escala PEDro.Resultados: Após administração dos critérios de inclusão/exclusão 16 estudos foram selecionados (karatê: seis; judô: cinco; taekwondo: dois; taichi: dois e artes marciais mistas: um), totalizando 310 pessoas com deficiência intelectual avaliadas. Os tipos de deficiência intelectual investigados foram Síndrome de Down (n=21), deficiência intelectual grave e moderada (n=45), transtorno do espectro autista (n=135), deficiência intelectual não especificada com Coeficiente intelectual <70 (n=66), deficiência intelectual “educável” (n=32) e epilepsia (n=11). Os principais resultados apontam para melhoria em aspectos da aptidão física e também do desempenho motor. Aspectos de socialização e do comportamento apresentam resultados conflitantes.Conclusão: Existem efeitos positivos oriundos da prática de artes marciais, contudo variáveis comportamentais ainda carecem de evidência em pessoas com deficiência intelectual. A baixa qualidade metodológica dos estudos releva a necessidade de mais pesquisas de qualidade, randomizadas e controladas, e incluindo outras artes marciais acessíveis ao público com deficiência intelectual. (AU)

Efectos de la práctica de artes marciales en la aptitud física y las características de comportamiento de personas con discapacidad intelectual: una revisión sistemáticaRESUMENIntroducción: La actividad física y el deporte reducen el riesgo de desarrollar enfermedades en personas con discapacidad intelectual (DI), sin embargo, algunos deportes carecen de información al respecto, como las artes marciales.Objetivo: presentar los efectos relacionados con la práctica de artes marciales para personas con discapacidad intelectual.Método: dos evaluadores independientes realizaron una búsqueda sistemática en seis bases de datos. Los estudios deben aportar información clara sobre los participantes y las características de las intervenciones. La calidad de los estudios se evaluó mediante la escala PEDro.Resultados: Después de los criterios de inclusión/exclusión, se seleccionaron 16 estudios (karate: seis; judo: cinco; taekwondo: dos; taichi: dos y artes marciales mixtas: uno), con un total de 310 personas evaluadas. Los tipos de deficiência intelectual investigados fueron Síndrome de Down (n = 21), deficiencia intelectual grave y moderada (n = 45), trastorno del espectro autista (n = 135), deficiencia intelectual no especificada con coeficiente intelectual <70 (n = 66), deficiencia intelectual "educable” (n = 32) y epilepsia (n = 11). Los principales resultados apuntan a una mejora en aspectos de la condición física y también el rendimiento motor. Los aspectos de socialización y comportamiento muestran resultados contradictorios.Conclusión: la práctica de artes marciales tiene efectos positivos, sin embargo, las variables de comportamiento aún carecen de evidencia en personas con deficiencia intelectual. La baja calidad metodológica de los estudios subraya la necesidad de una investigación de mayor calidad, aleatorizada y controlada, e incluyendo otras artes marciales accesibles al público con identificación. (AU)

Introduction: Physical activity and sport have important reductions in the risk of developing diseases in persons with intellectual disabilities (ID), however, some sports still lack information on their effectiveness, such as martial arts.Objective: Thus, our objective was to present the effects related to the practice of martial arts for people with intellectual disabilities.Method: A systematic search of six databases was carried out by two independent evaluators. The studies should bring clear information about the public with intellectual disabilities studied in addition to the characteristics that comprised the selected interventions. The quality of the studies was assessed using the PEDro scale.Results: After administering the inclusion/exclusion criteria, 16 studies were selected (karate: six; judo: five; taekwondo: two; taichi: two and mixed martial arts: one), totaling 310 people with ID assessed. The types of intellectual disabilities investigated were Down Syndrome (n = 21), severe and moderate intellectual disabilities (n = 45), autistic spectrum disorder (n = 135), unspecified intellectual disabilities with intelligence quotient <70 (n = 66), intellectual disabilities “educable”(n = 32) and epilepsy (n = 11). The main results point to improvement in aspects of physical fitness and also motor performance. Aspects of socialization and behavior show conflicting results.Conclusion: There are positive effects from the practice of martial arts, however behavioral variables still lack evidence in people with intellectual disabilities. The low methodological quality of the studies underscores the need for more quality research, randomized and controlled, and including other martial arts accessible to the public with intellectual disabilities. (AU)

Drivers' Spatio-Temporal Attentional Distributions Are Influenced by Vehicle Dynamics and Displayed Point of View.

OBJECTIVE: The aim of this study is to measure drivers' attention to preview and their velocity and acceleration tracking error to evaluate two- and three-dimensional displays for following a winding roadway. BACKGROUND: Display perturbation techniques and Fourier analysis of steering movements can be used to infer drivers' spatio-temporal distribution of attention to preview. Fourier analysis of tracking error time histories provides measures of position, velocity, and acceleration error. METHOD: Participants tracked a winding roadway with 1 s of preview in low-fidelity driving simulations. Position and rate-aided vehicle dynamics were paired with top-down and windshield displays of the roadway. RESULTS: For both vehicle dynamics, tracking was smoother with the windshield display. This display emphasizes nearer preview positions and has a closer correspondence to the control-theoretic optimal attentional distributions for these tasks than the top-down display. This correspondence is interpreted as a form of stimulus-response compatibility. The position error and attentional signal-to-noise ratios did not differ between the two displays with position control, but with more complex rate-aided control much higher position error and much lower attentional signal-to-noise ratios occurred with the top-down display. CONCLUSION: Display-driven influences on the distribution of attention may facilitate tracking with preview when they are similar to optimal attentional distributions derived from control theory. APPLICATION: Display perturbation techniques can be used to assess spatially distributed attention to evaluate displays and secondary tasks in the context of driving. This methodology can supplement eye movement measurements to determine what information is guiding drivers' actions.

Virtual and augmented reality in a simulated naval engagement: Preliminary comparisons of simulator sickness and human performance.

The aim of this study was to compare simulator sickness symptoms while participants wore either a virtual reality (VR) or augmented reality (AR) headset. A secondary aim involved comparing how physical motion affects symptoms. During a simulation, participants wore VR and AR headsets while standing on a motion platform and firing at hostile ships under three motion conditions: No Physical Motion; Synchronous Motion, in which the physical and displayed motion were coupled; and Asynchronous Motion, in which the physical motion did not match the display. Symptoms increased over time but were not different with respect to headset or motion. The VR condition had higher accuracy and faster response time to the commence fire instruction. Further research is necessary to determine if this holds under more extreme motion. The use of VR or AR headsets for training under gentle motion conditions is practicable and should be permissible under normal conditions during deployment.

Studying Gaze Behavior to Compare Three Different Hazard Perception Tasks.

OBJECTIVE: The aim of the current study was to compare the traditional, verbal, and motoric tasks regarding their contributions to hazard perception measurement. BACKGROUND: Traditional hazard perception tasks require the participants to respond to filmed traffic conflicts in an imprecise way, such as by pressing a button. More sophisticated tasks include either verbal specification or motoric localization of the perceived hazards. The present study investigated the participants' gaze behavior when they were provided with an identical set of traffic animations but were instructed to perform one of three types of hazard perception tasks. METHOD: In an eye tracking study, 69 drivers were shown animated traffic scenarios and instructed to perform the traditional (press button), verbal, or speeded motoric localization hazard perception task. Eye tracking revealed whether and when the participant had fixated a certain hazard cue. RESULTS: The participants in the traditional task group were slower to fixate emerging hazards, but quicker to respond to them than the participants of the verbal and the motoric groups. As a specific benefit, the verbal task differentiated between different types of failures. CONCLUSION: Additional verbal or speeded motoric localization tasks seem to have increased the participants' alertness when watching the animations. The verbal task provides valuable additional information regarding the participants' performance. To approximate real-life hazard perception ability, it is recommended that researchers and practitioners use a combination of different hazard perception tasks for assessment and training.

Task-specific adaptations of postural sway in sitting infants.

When engaging in manual or visual tasks while sitting, infants modify their postural sway based on concurrent task demands. It remains unclear whether these modulations are sensitive to differences in concurrent task demands (holding a toy vs. looking at a toy being held by someone else), and whether the properties of the support surface impact these adaptations. We investigated infants' ability to modify postural sway when holding a toy or visually attending to a toy someone else was holding while sitting on different support surfaces. Twenty-six independently sitting infants sat on solid and compliant surfaces placed on a force plate while looking at or holding a toy. Measures of postural sway were calculated from the center of pressure data. Visually attending to a toy was associated with less sway and lower sway velocity than when holding a toy. Surprisingly, surface compliance did not affect sway and there were no interaction effects. Whereas sway modulations may facilitate infants' performance on both manual and visual concurrent tasks, the visual task placed more constraints on the postural system leading to greater adaptations in postural sway. These findings provide insights into how infants are allocating attention and coordinating perceptual-motor information in developing sitting skills.

Why do bad balls get wickets? The role of congruent and incongruent information in anticipation.

Skilled anticipation is underpinned by the use of kinematic and contextual information. However, few researchers have examined what happens when contextual information suggests an outcome that is different from the event that follows. We aimed to bridge this gap by manipulating the relationship between contextual information and final ball location in a cricket-batting task. We predicted that when contextual information is congruent with the eventual outcome then anticipation would be facilitated. In contrast, when contextual information is incongruent, this would lead to a confirmation bias on kinematic information and result in decreased anticipation accuracy. We expected this effect to be larger in skilled performers who are more able to utilise context. Skilled and less-skilled cricket batters anticipated deliveries presented using a temporally occluded video-based task. We created conditions whereby contextual information and event outcome were either congruent or incongruent. There was a significant skill by condition interaction (p < 0.05). The skilled group anticipated significantly more accurately than the less-skilled group on the congruent trials. Both groups anticipated less accurately on incongruent trials, with the skilled participants being more negatively affected. Skilled performers prioritise contextual information and confirmation bias affects the use of kinematic information available later in the action.

Assessment of Performance Carryover Effects Due to Successive Exposure to Different Lateral Camera Rotations in a Laparoscopic Training Environment.

Objective The aim of this study was to assess performance carryover effects associated with different successive lateral camera rotations in the laparoscopic training environment. Background Laparoscopy requires surgeons to adapt to disruptions of visuomotor mapping. A gradual adaptation process is hypothesized to be effective up to a given rotation threshold; this threshold may have performance implications for successive exposure to different lateral camera rotations. Method Two experiments utilized a laparoscopic training task. Experiment 1 exposed novices to a subsequent rotation that was either 45° larger than one of the initial rotations of 45°, 75°, 105°, and 135° or 45° smaller than one of the initial rotations of 90°, 120°, 150°, and 180°. Experiment 2 exposed novices to either stepwise increasing rotations (0° to 180°) or stepwise decreasing rotations (180° to 0°). Results Regarding Experiment 1, performance generally improved for subsequent rotations that were 45° larger than the initial rotation, except for one condition (initial rotation, 105°; subsequent rotation, 150°). Performance generally improved for subsequent rotations that were 45° smaller than the initial rotation, except for one condition (initial rotation, 120°; subsequent rotation, 75°). Experiment 2 indicated worst performance at 120° for the increasing and decreasing conditions. This finding suggests an identical threshold for increasing and decreasing rotations, which is inconsistent with Experiment 1 results. Conclusion Improved performance due to carryover effects from successive exposure to lateral camera rotations in the laparoscopic training environment is contingent on the specific camera rotations. Application Supplementary laparoscopic training might be needed for surgeries that entail certain successive lateral camera rotations.

Measuring Memory and Attention to Preview in Motion.

Objective Use perceptual-motor responses to perturbations to reveal the spatio-temporal detail of memory for the recent past and attention to preview when participants track a winding roadway. Background Memory of the recently passed roadway can be inferred from feedback control models of the participants' manual movement patterns. Similarly, attention to preview of the upcoming roadway can be inferred from feedforward control models of manual movement patterns. Method Perturbation techniques were used to measure these memory and attention functions. Results In a laboratory tracking task, the bandwidth of lateral roadway deviations was found to primarily influence memory for the past roadway rather than attention to preview. A secondary auditory/verbal/vocal memory task resulted in higher velocity error and acceleration error in the tracking task but did not affect attention to preview. Attention to preview was affected by the frequency pattern of sinusoidal perturbations of the roadway. Conclusion Perturbation techniques permit measurement of the spatio-temporal span of memory and attention to preview that affect tracking a winding roadway. They also provide new ways to explore goal-directed forgetting and spatially distributed attention in the context of movement. More generally, these techniques provide sensitive measures of individual differences in cognitive aspects of action. Application Models of driving behavior and assessment of driving skill may benefit from more detailed spatio-temporal measurement of attention to preview.

Low-Carbohydrate-High-Fat Diet: Can it Help Exercise Performance?

Low-carbohydrate-high-fat (LCHF) diets have been used as a means of weight loss and control of symptoms in several clinical conditions. There is emerging evidence that the metabolic changes induced by LCHF diets enhance endurance performance. The aims of this review are to examine the evidence of LCHF diets in improving various aspects of athletic performance. Long-term LCHF dietary intake may help control body weight and fat mass while maintaining lean body mass in athletes in weight-sensitive sports. LCHF-adapted endurance athletes can reach the maximal fat oxidation rate of approximately 1.5 g/min, with a lower carbohydrate oxidation rate and similar muscle glycogen content and a resynthesis rate compared to their counterparts consuming high-carbohydrate-low-fat (HCLF) diets. The elevated fat oxidation rate and glycogen sparing effect may improve performance in ultra-endurance events. These metabolic changes may also prevent the decline in performance in later stages of repeated high-intensity movements, in which the aerobic metabolism becomes more important. However, elevated blood concentrations of non-esterified fatty acids and ammonia during exercise after LCHF diets may lead to early development of central fatigue. It appears that at least several months of adaptation to a LCHF diet are required for the metabolic changes and restoration of muscle glycogen to occur. Further investigations on LCHF diets are needed regarding (1) performance after weight loss in weight-categorized sports; (2) repeated high-intensity exercise performance; (3) development of central fatigue during endurance events; (4) perceptual-motor performance during prolonged intermittent sports; and (5) ideal dietary fatty acid compositions.

Perceptual-motor learning benefits from increased stress and anxiety.

The purpose of this study was to manipulate psychological stress and anxiety to investigate effects on ensuing perceptual-motor learning. Thirty-six participants attended two experimental sessions separated by 24h. In the first session, participants were randomized to either a mental arithmetic task known to increase stress and anxiety levels or a control condition and subsequently completed training on a speeded precision pinch task. Learning of the pinch task was assessed at the second session. Those exposed to the high stress-anxiety mental arithmetic task prior to training reported elevated levels of both stress and anxiety and demonstrated shorter movement times and improved retention of movement accuracy and movement variability. Response execution processes appear to benefit from elevated states of stress and anxiety immediately prior to training even when elicited by an unrelated task.

Flying the Needles: Flight Deck Automation Erodes Fine-Motor Flying Skills Among Airline Pilots.

OBJECTIVE: The aim of this study was to evaluate the influence of practice and training on fine-motor flying skills during a manual instrument landing system (ILS) approach. BACKGROUND: There is an ongoing debate that manual flying skills of long-haul crews suffer from a lack of flight practice due to conducting only a few flights per month and the intensive use of automation. However, objective evidence is rare. METHOD: One hundred twenty-six randomly selected airline pilots had to perform a manual flight scenario with a raw data precision approach. Pilots were assigned to four equal groups according to their level of practice and training by fleet (short-haul, long-haul) and rank (first officer, captain). RESULTS: Average ILS deviation scores differed significantly in relation to the group assignments. The strongest predictor variable was fleet, indicating degraded performance among long-haul pilots. CONCLUSION: Manual flying skills are subject to erosion due to a lack of practice on long-haul fleets: All results support the conclusion that recent flight practice is a significantly stronger predictor for fine-motor flying performance than the time period since flight school or even the total or type-specific flight experience. APPLICATION: Long-haul crews have to be supported in a timely manner by adequate training tailored to address manual skills or by operational provisions like mixed-fleet flying or more frequent transitions between short-haul and long-haul operation.

Do Tele-Operators Learn to Better Judge Whether a Robot Can Pass Through an Aperture?

OBJECTIVE: This experiment examined whether tele-operators learn to better judge a robot's ability to pass through an aperture, hereafter referred to as pass-ability judgments, and detailed the nature of such learning. BACKGROUND: Jones, Johnson, and Schmidlin reported that tele-operators' pass-ability judgments did not improve over the course of their experiment, which was surprising. METHOD: In each of seven blocks, tele-operators made pass-ability judgments about 10 apertures whose width varied. During each trial, participants drove the robot toward the aperture, answered yes or no to whether it could pass through that aperture, and then attempted to drive the robot through the aperture. Pass-ability judgments were analyzed in terms of percentage correct and absolute thresholds; the latter mimicked how Jones et al. analyzed their data. RESULTS: Learning was revealed when judgments were analyzed in terms of percentage correct and not when analyzed in terms of absolute thresholds. Further analyses revealed that tele-operators only improved their pass-ability judgments for impassable apertures, and tele-operators' perceptual sensitivity and response bias changed over the course of the experiment. CONCLUSION: The percentage correct-based analyses revealed that tele-operators learned to make better pass-ability judgments. Jones et al.'s decision to analyze their data in terms of absolute thresholds obscured learning. APPLICATION: The present results suggested that researchers should employ percentage correct when studying learning in this domain, training protocols should focus on improving tele-operators' abilities to judge the pass-ability of impassable apertures, and tele-operators truly learned to better discriminate passable and impassable apertures.

Neurología de la anticipación y sus implicaciones en el deporte / Anticipation neurology and its implications in sports

El movimiento es una acción que involucra interconexiones complejas, por lo cual se requiere profundizar en los procesos de adaptación, predicción y anticipación que permiten entender la importancia de estos aspectos desde sus bases filogenéticas y ontogenéticas hasta su implicación en movimientos complejos. Parte de la optimización de los procesos descritos se haya en la calidad de información aferente, la cual permite la relación con el entorno -especialmente la entrada visual- que reconoce un flujo de imágenes y una proyección al contexto en el que se está inmerso. Las estructuras e interconexiones implicadas en la anticipación y predicción de movimientos son descritas de modo que se evidencia la congruencia y continuidad del flujo de información que caracteriza esta especialidad neuromecánica de movimiento. Por otro lado, se aborda la integración de centros puntuales del sistema nervioso central y redes neuronales que permiten el entramado de procesos de aprendizaje por observación, además de proveer equilibrio y eficiencia al sistema en la recepción de estímulos y su relación con la generación de eferencias motoras que cumplan con objetivos específicos. En el ámbito deportivo estos procesos favorecen la eficiencia del gesto optimizando el movimiento.

Movement involves complex interconnections. It is required to deeply examine the adaptation, prediction and anticipation processes to understand their importance from the phylogenetic and ontogenetic bases, until its involvement in complex movements. Part of the optimization of these processes is found in the quality of afferent input, which allows the connection with the environment, in particular, the visual input, which recognizes an image stream and a projection to the context in which it is immersed. Those structures and interconnections involved in the anticipation and prediction of movements are described so that the consistency and the constant transfer of information that characterizes this field of neuromechanical movement speciality are evidenced. In addition, this article addresses the integration of specific centers from the Central Nervous System and the neural networks that allow the network of learning processes by observation, and that also provide balance and efficiency to the system in receiving stimuli and their relationship with the generation of motor efferents that accomplish specific objectives. In sports, these processes favor the gesture efficience optimizing the movement.

The impact of personality traits and professional experience on police officers' shooting performance under pressure.

We explored the impact of professional experience and personality on police officers' shooting performance under pressure. We recruited: (1) regular officers, (2) officers wanting to join a specialised arrest unit (AU) (expected to possess more stress-resistant traits; pre-AU) and (3) officers from this unit (expected to also possess more professional experience; AU) (all male). In Phase 1, we determined personality traits and experience. In Phase 2, state anxiety, shot accuracy, decision-making (shoot/don't shoot), movement speed and gaze behaviour were measured while officers performed a shooting test under low and high pressure. Results indicate minimal differences in personality among groups and superior performance of AU officers. Regression analyses showed that state anxiety and shooting performance under high pressure were first predicted by AU experience and second by certain personality traits. Results suggest that although personality traits attenuate the impact of high pressure, it is relevant experience that secures effective performance under pressure. Practitioner Summary: To obtain information for police selection and training purposes, we let officers who differed in personality and experience execute a shooting test under low and high pressure. Outcomes indicate that experience affected anxiety and performance most strongly, while personality traits of thrill- and adventure-seeking and self-control also had an effect.

Decision-related action orientation predicts police officers' shooting performance under pressure.

BACKGROUND AND OBJECTIVES: We aimed to test whether police officers' trait self-control strength decreases negative effects of high pressure (HP) on state anxiety, shooting behavior, and shooting performance. DESIGN AND METHODS: Forty-two officers performed a shooting test under both high and low-pressure (LP) conditions. Self-control strength was assessed with the decision-related action orientation (AOD) scale of the Action Control Scale (ACS-90). Effects of AOD on perceived anxiety, heart rate, shooting time, and shot accuracy were estimated and controlled for those of other individual difference measures (i.e. age, police working experience, trait anxiety, and threat-related action orientation). RESULTS: After controlling for baseline values in the LP condition as well as the other individual difference measures, AOD significantly predicted shot accuracy in the HP condition. CONCLUSIONS: Results suggest that trait self-control strength in the form of AOD helps officers cope with anxiety and maintain perceptual-motor performance under HP.

Motor Learning and Movement Performance: Older versus Younger Adults.

INTRODUCTION: Motor skills play an important role during life span, and older adults need to learn or relearn these skills. The purpose of this study was to investigate how aging affects induction of improved movement performance by motor training. METHODS: Serial Reaction Time Test (SRTT) was used to assess movement performance during 8 blocks of motor training. Participants were tested in two separate dates, 48 hours apart. First session included 8 blocks of training (blocks 1-8) and second session comprised 2 blocks (blocks 9, 10). RESULTS: Analyses of data showed that reaction times in both online and offline learning were significantly shorter in older adults compared to younger adults (P<0.001). Young adults demonstrated both online and offline learning (P<0.001), but older adults only showed online learning (P<0.001) without offline learning (P=0.24). DISCUSSION: The result of the current study provides evidence that the healthy older adults are able to improve their performance with practice and learn motor skill successfully in the form of online learning.