Rouwen Cañal-Bruland

Global information pickup underpins anticipation of tennis shot direction

The authors examined the importance of local dynamical information when anticipating tennis shot direction. In separate experiments, they occluded the arm and racket, shoulders, hips, trunk, and legs and locally neutralized dynamical differences between shot directions, respectively. The authors examined the impact of these manipulations on resulting (display) dynamics and the ability of participants with varying perceptual skills to anticipate shot direction. The occlusion manipulation affected the display dynamics to a larger extent than did the neutralization manipulation. Although the authors observed a decrement in performance when local information from the arm and racket was occluded or neutralized and when information from the trunk and legs was neutralized, the results generally suggest that participants anticipated shot direction through a more global perceptual approach, particularly in perceptually skilled participants.

Response bias in judging deceptive movements

Two not mutually exclusive explanations, perceptual and motor expertise, account for the finding that experts outperform novices in recognizing deceptive actions from bodily (kinematic) cues. The aim of the present study was twofold: First, we sought to examine the impact of motor and perceptual expertise on distinguishing deceptive and non-deceptive actions. Second, we tested the hypothesis that differences in perceptual judgments on deceptive movements vs. non-deceptive movements do not necessarily need to be caused by either perceptual or motor expertise differences, but can also be a result of response bias. Skilled handball players (field players and goalkeepers) and novices had to detect whether a penalty-taker shot or faked a shot at the goal. Signal detection theory (SDT) analysis revealed that skilled handball players outperformed novices in discriminating shots from fakes. No differences in perceptual sensitivity were found between the goalkeepers and the field players. However, SDT analysis showed that goalkeepers were significantly biased to judge movements as deceptive, while neither field players nor novices showed this response bias.

An examination of motor and perceptual contributions to the recognition of deception from others' actions

Most empirical studies thus far have confounded motor and perceptual experience when examining their contributions to the recognition of deceptive and non-deceptive intentions from another persons movements. In the present study, we manipulated viewing perspective as an additional demarcation to examine the involvement of motor and perceptual experience in detecting deceptive intentions. Expert handball players (N=26), expert handball goalkeepers (N=19), and a group of novices (N=20) were required to indicate whether a penalty-taker produced a true or a fake shot. The clips were shown from a front view (i.e., a goalkeepers customary viewing perspective) and a (more neutral) side view, and ended one frame before the ball would be released from the hand. Results indicated that expert players and goalkeepers outperformed novices in detecting deceptive intentions, but there were no differences between field players and goalkeepers. Recognition of deceptive actions was more accurate from the goalkeepers front view than from the side view. We conclude that neither the degree of motor experience nor the degree of perceptual experience can, in themselves, account for explaining successful recognition of deceptive actions.

Action goals influence action-specific perception

We examined the processes that mediate the emergence of action-specific influences on perception that have recently been reported for baseball batting and golf putting (Witt, Linkenauger, Bakdash, & Proffitt, 2008; Witt & Proffitt, 2005). To this end, we used a Schokokusswurfmaschine: Children threw a ball at a target, which, if hit successfully, launched a ball that the children then had to catch. In two experiments, children performed either a throwing-and-catching task or a throwing-only task, in which no ball was launched. After each task, the size of the target or of the ball was estimated. Results indicate that action-specific influences on perceived size occur for objects that are related to the end goal of the action, but not for objects that are related to intermediate action goals. These results suggest that action-specific influences on perception are contingent upon the primary action goals to be achieved.

Visual perception in fencing: Do the eye movements of fencers represent their information pickup?

The present study examined whether results of athletes’ eye movements while they observe fencing attacks reflect their actual information pickup by comparing these results with others gained with temporal and spatial occlusion and cuing techniques. Fifteen top-ranking expert fencers, 15 advanced fencers, and 32 sport students predicted the target region of 405 fencing attacks on a computer monitor. Results of eye movement recordings showed a stronger foveal fixation on the opponent’s trunk and weapon in the two fencer groups. Top-ranking expert fencers fixated particularly on the upper trunk. This matched their performance decrements in the spatial occlusion condition. However, when the upper trunk was occluded, participants also shifted eye movements to neighboring body regions. Adding cues to the video material had no positive effects on prediction performance. We conclude that gaze behavior does not necessarily represent information pickup, but that studies applying the spatial occlusion paradigm should also register eye movements to avoid underestimating the information contributed by occluded regions.

The influence of anxiety on action-specific perception

Abstract Recent empirical research suggests that performance modulates perception. For example, baseball players judge the ball to be bigger when performing well as compared to when performing less successfully. Yet, the underlying processes that mediate the emergence of action-specific effects on perception are still largely unknown. To this end, we aimed to examine the impact of anxiety on the action-specific influence on perception as anxiety has been shown to affect both performance and perception. Thirty participants threw darts at a circle-shaped target and were then asked to judge the size of the target. The task was performed under conditions of low and high anxiety. Results replicated previously reported action-specific effects on perception under levels of low anxiety. However, these effects vanished in the high anxiety condition. Results seem to suggest that anxiety has a direct influence on the relation between performance and perception. Attentional control theory is discussed to explain the current findings.

Keeping an eye on the violinist: motor experts show superior timing consistency in a visual perception task

Common coding theory states that perception and action may reciprocally induce each other. Consequently, motor expertise should map onto perceptual consistency in specific tasks such as predicting the exact timing of a musical entry. To test this hypothesis, ten string musicians (motor experts), ten non-string musicians (visual experts), and ten non-musicians were asked to watch progressively occluded video recordings of a first violinist indicating entries to fellow members of a string quartet. Participants synchronised with the perceived timing of the musical entries. Results revealed significant effects of motor expertise on perception. Compared to visual experts and non-musicians, string players not only responded more accurately, but also with less timing variability. These findings provide evidence that motor experts’ consistency in movement execution—a key characteristic of expert motor performance—is mirrored in lower variability in perceptual judgements, indicating close links between action competence and perception.

Time to broaden the scope of research on anticipatory behavior: a case for the role of probabilistic information

Over the past four decades we have seen a dramatic improvement in our understanding of the processes that underpin the anticipatory behavior of skilled performers in domains such as sport. Early research by Jones and Miles (1978) and Salmela and Fiorito (1979) inspired and fuelled the research of todays leaders in the field such as Abernethy (1990), Savelsbergh et al. (2002), and Williams and Davids (1998), and many of us who follow in their footsteps. Originally, the key question driving this research was whether skilled performers of temporally constrained sport tasks (e.g., returning a tennis serve or hitting a baseball) are better than less-skilled performers in their ability to make use of kinematic information from an opponents action. After confirming the expert advantage in anticipation, research then focused on identifying the kinematic sources of information that underpin the superior anticipatory behavior. This research made use of a variety of experimental paradigms including temporal and spatial occlusion techniques, point-light displays, and gaze tracking (for a review see Mann and Savelsbergh, 2015). Since the 1970s an impressive body of empirical data has been generated that has led to useful practical outcomes for the individual sports examined, and that at the same time have resulted in more generalizable findings across sports, thereby generating a better understanding of the mechanisms underlying expert anticipation. As a case in point, it is now generally accepted that experts tend to make use of fewer fixations of longer duration when trying to predict the outcome of an opponents action (for a meta-analysis supporting this conclusion, see e.g., Mann et al., 2007). There can be little doubt that this research focusing on the kinematic sources of information that facilitate the prediction of action outcomes has proven to be very insightful and important for furthering our understanding of expert anticipation in sports (Abernethy, 1990; Williams and Davids, 1998). Likewise, this research has been crucial for generating evidence-based recommendations for the best means to train anticipatory skill. However, here we call for a broadening in the scope of anticipation research in an attempt to further improve and enrich our understanding of expert anticipation in sport. This call is based on the high proportion of studies performed examining anticipatory behavior on the basis of kinematic sources of information, yet a relative paucity in studies that take into consideration the influence of broader situational or contextual (non-kinematic) sources of information. As early as in the late 1970s researchers identified that anticipatory behavior may at least in part be informed by probabilistic information that is independent of the observed movement, and hence also independent of the visual information that can be picked up from such movements (e.g., Alain and Girardin, 1978; Alain and Proteau, 1980). It was Abernethy et al. (2001) who—more than 20 years after the original observations had been published—revisited how other non-kinematic, contextual information may contribute and influence how experts anticipate action outcomes. In their seminal paper, Abernethy et al. (2001) showed that probabilistic information that they coined situational probabilities could be used to anticipate action outcomes in the absence of any movement information from the opponent (in that case by evaluating the court position of the opponent in squash). Since then, only recently have a handful of studies started to systematically examine the contribution of situational probability (or contextual) information to anticipatory behavior. This includes the impact of probabilistic information such as playing patterns related to the game score (Farrow and Reid, 2012); exposure to an individuals action preferences (Navia et al., 2013; Mann et al., 2014); exposure to previous outcome sequences (Loffing et al., 2015); how an opponents court position interacts with kinematically-driven judgments (Loffing and Hagemann, 2014); and how contextual information influences both gaze behavior (McRobert et al., 2011) and the cognitive processes underpinning anticipatory skill (Murphy et al., 2015). Moreover, it has been shown that the anticipatory behavior of skilled performers is influenced by their assessment of the relative costs and benefits of responding or not responding (Canal-Bruland and Schmidt, 2009; Canal-Bruland et al., 2015). Further, work on the use of simple heuristics also indicates that experts tend to use various sources of information to make fast judgments under conditions of uncertainty that in sports include situations which require the initiation of action responses even before reliable visual information is available (Raab, 2012; de Oliveira et al., 2014). Together, these findings strongly support the idea that factors other than visual information conveyed in the observed kinematics do also play a significant role in successful anticipatory behavior. Given that these recent studies have highlighted a surprisingly large role for contextual information in supporting anticipatory behavior, we advocate that more research is needed in this area to bring us closer to the original aim, namely, to understand the superior anticipatory skill of experts. To reach this ultimate objective, in our view, research is needed to identify: (1) the contextual (non-kinematic) sources of information that influence anticipatory behavior; (2) how skilled performers combine these non-kinematic contextual sources of information with (i) each other and (ii) with real-time (kinematic) information from an opponents actions; and (3) how the way that the information is combined is shaped by the circumstances in which the behavior is performed.

Recognizing and predicting movement effects: identifying critical movement features.

It is not clear whether the critical features used to discriminate movements are identical to those involved in predicting the same movements effects and consequently, whether the mechanisms underlying recognition and anticipation differ. We examined whether people rely on different kinematic information when required to recognize differences in the movement pattern in comparison to when they have to anticipate the outcome of these same movements. Naïve participants were presented with paired presentations of point-light animated tennis shots that ended at racket-ball contact. We instructed them either to judge whether the movements observed were the same or different or to predict shot direction (left vs. right). In addition, we locally manipulated the kinematics of point-light figures in an effort to identify the critical features used when making recognition and anticipation judgments. It appears that observers rely on different sources of information when required to recognize movement differences compared to when they need to anticipate the outcome of the same observed movements. Findings are discussed with reference to recent ideas focusing on the role of perceptual and motor resonance in perceptual judgments.

Target-directed visual attention is a prerequisite for action-specific perception

Witt et al. (2008) have recently shown that golfers who putt with more success perceive the hole to be bigger than golfers who putt with less success. In three experiments, we systematically examined whether this phenomenon, labelled action-specific perception, depends on directing visual attention towards the action target. In Experiment 1 we replicated previously reported action-specific effects on perception in golf putting. In Experiments 2 and 3 we directly assessed whether action-specific effects on perception in golf putting are dependent on focusing visual attention on the target. To this end, the participants performed the putting task while visual attention towards the target was either completely withheld (Experiment 2) or divided over the target and other task-relevant objects (Experiment 3). No action-specific effects were found when visual attention towards the action target was occluded or partially diverted from the target. Together, our results provide evidence to suggest that focusing visual attention on the target while performing the action is a prerequisite for the emergence of action-specific perception.