Increasing auditory intensity enhances temporal but deteriorates spatial accuracy in a virtual interception task.

Humans are quite accurate and precise in interception performance. So far, it is still unclear what role auditory information plays in spatiotemporal accuracy and consistency during interception. In the current study, interception performance was measured as the spatiotemporal accuracy and consistency of when and where a virtual ball was intercepted on a visible line displayed on a screen based on auditory information alone. We predicted that participants would more accurately indicate when the ball would cross a target line than where it would cross the line, because human hearing is particularly sensitive to temporal parameters. In a within-subject design, we manipulated auditory intensity (52, 61, 70, 79, 88 dB) using a sound stimulus programmed to be perceived over the screen in an inverted C-shape trajectory. Results showed that the louder the sound, the better was temporal accuracy, but the worse was spatial accuracy. We argue that louder sounds increased attention toward auditory information when performing interception judgments. How balls are intercepted and practically how intensity of sound may add to temporal accuracy and consistency is discussed from a theoretical perspective of modality-specific interception behavior.

Embodied decision biases: individually stable across different tasks?

In everyday life, action and decision-making often run in parallel. Action-based models argue that action and decision-making strongly interact and, more specifically, that action can bias decision-making. This embodied decision bias is thought to originate from changes in motor costs and/or cognitive crosstalk. Recent research confirmed embodied decision biases for different tasks including walking and manual movements. Yet, whether such biases generalize within individuals across different tasks remains to be determined. To test this, we used two different decision-making tasks that have independently been shown to reliably produce embodied decision biases. In a within-participant design, participants performed two tasks in a counterbalanced fashion: (i) a walking paradigm for which it is known that motor costs systematically influence reward decisions, and (ii) a manual movement task in which motor costs and cognitive crosstalk have been shown to impact reward decisions. In both tasks, we successfully replicated the predicted embodied decision biases. However, there was no evidence that the strength of the biases correlated between tasks. Hence, our findings do not confirm that embodied decision biases transfer between tasks. Future research is needed to examine whether this lack of transfer may be due to different causes underlying the impact of motor costs on decisions and the impact of cognitive crosstalk or task-specific differences.

Embodied choices bypass narratives under radical uncertainty.

Johnson et al. suggest that we rely on narratives to make choices under radical uncertainty. We argue that in its current version Conviction Narrative Theory (CNT) does not account for embodied, direct sensorimotor influences on choices under radical uncertainty that may bypass narratives, particularly in highly time-constrained situations. We therefore suggest to extend CNT by an embodied choice perspective.

Embodied decisions during walking.

Research on embodied decision-making only recently started to examine whether and how concurrent actions influence value-based decisions. For instance, during walking humans preferably make decisions that align with a turn toward the side of their current swing leg, sometimes resulting in unfavorable choices (e.g., less reward). It is suggested that concurrent movements influence decision-making by coincidental changes in motor costs. If this is true, systematic manipulations of motor costs should bias decisions. To test this, participants had to accumulate rewards (i.e., points) by walking and turning toward left and right targets displaying rewards across three experiments. In experiments 1a and 1b, we manipulated the turning cost based on the current swing leg by applying different symmetric turning magnitudes (i.e., same angles for left and right targets). In experiment 2, we manipulated the turning cost by administering asymmetric turning magnitudes (i.e., different angles for left and right targets). Finally, in experiment 3, we increased the cost of walking by adding ankle weights. Altogether, the experiments support the claim that differences in motor costs influenced participants' decisions: experiments 1a and 1b revealed that the swing leg effect and stepping behavior were moderated by turning magnitude. In experiment 2, participants showed a preference for less costly, smaller turning magnitudes. Experiment 3 replicated the swing leg effect when motor costs were increased by means of ankle weights. In conclusion, these findings provide further evidence that value-based decisions during ongoing actions seem to be influenced by dynamically changing motor costs, thereby supporting the concept of "embodied decision-making."NEW & NOTEWORTHY Motor processes of concurrent movements have been shown to influence embodied decision-making. It is hypothesized that this is driven by coincidental changes in motor costs. We tested this claim by systematically manipulating motor costs of choice options during walking. In three experiments we show how variations in motor cost (e.g., turning angle or stepping constraints) bias decision-making, thereby supporting the concept of "embodied decision-making."

Auditory perception dominates in motor rhythm reproduction.

It is commonly agreed that vision is more sensitive to spatial information, while audition is more sensitive to temporal information. When both visual and auditory information are available simultaneously, the modality appropriateness hypothesis predicts that, depending on the task, the most appropriate (i.e., reliable) modality dominates perception. While previous research mainly focused on discrepant information from different sensory inputs to scrutinize the modality appropriateness hypothesis, the current study aimed at investigating the modality appropriateness hypothesis when multimodal information was provided in a nondiscrepant and simultaneous manner. To this end, participants performed a temporal rhythm reproduction task for which the auditory modality is known to be the most appropriate. The experiment comprised an auditory (i.e., beeps), a visual (i.e., flashing dots), and an audiovisual condition (i.e., beeps and dots simultaneously). Moreover, constant as well as variable interstimulus intervals were implemented. Results revealed higher accuracy and lower variability in the auditory condition for both interstimulus interval types when compared to the visual condition. More importantly, there were no differences between the auditory and the audiovisual condition across both interstimulus interval types. This indicates that the auditory modality dominated multimodal perception in the task, whereas the visual modality was disregarded and hence did not add to reproduction performance.

The impact of co-acting competitors on shooting performance in elite biathletes.

Grounded in social facilitation theory, this study examined the impact of co-acting competitors (i.e., opponents) on elite biathletes' shooting performance based on World Cup competition data. To this end, the impact of the number as well as the mean overlapping time with co-acting competitors at the shooting range on both shooting time and shooting accuracy was assessed. Competition data of World Cup races from 2005 to 2020 were analysed. This included 115 mass start and 195 pursuit events of a total of 758 elite biathletes amounting to 57.251 shooting bouts equivalent to a total of 286.255 shots. Data was analysed using a fixed effects model. Results revealed two main findings: First, the more co-acting opponents were present at the shooting range, the shorter (i.e., better) was shooting time. However, more co-acting opponents were also associated with decreased shooting accuracy in mass start, but not in pursuit. Second, a longer temporal overlap with co-acting opponents negatively affected biathletes' shooting time. There was no effect on shooting accuracy. To conclude, the present study provides first evidence for a link between co-acting competitors and shooting performance in elite biathletes by analysing ecologically valid, real world data.

Effects of visual blur and contrast on spatial and temporal precision in manual interception.

The visual system is said to be especially sensitive towards spatial but lesser so towards temporal information. To test this, in two experiments, we systematically reduced the acuity and contrast of a visual stimulus and examined the impact on spatial and temporal precision (and accuracy) in a manual interception task. In Experiment 1, we blurred a virtual, to-be-intercepted moving circle (ball). Participants were asked to indicate (i.e., finger tap) on a touchscreen where and when the virtual ball crossed a ground line. As a measure of spatial and temporal accuracy and precision, we analyzed the constant and variable errors, respectively. With increasing blur, the spatial and temporal variable error, as well as the spatial constant error increased, while the temporal constant error decreased. Because in the first experiment, blur was potentially confounded with contrast, in Experiment 2, we re-ran the experiment with one difference: instead of blur, we included five levels of contrast matched to the blur levels. We found no systematic effects of contrast. Our findings confirm that blurring vision decreases spatial precision and accuracy and that the effects were not mediated by concomitant changes in contrast. However, blurring vision also affected temporal precision and accuracy, thereby questioning the generalizability of the theoretical predictions to the applied interception task.

Body-specific influences on performance evaluation in realistic dynamic scenes.

According to the body-specificity hypothesis, left-handers (right-handers) are more likely to associate positive attributes with the left (right) side. We tested whether such body-specific influences also apply to evaluative judgments in realistic dynamic scenes. In two experiments (order counterbalanced), N = 231 participants watched videos from dual mogul competition where two skiers turn downhill through moguls side by side simultaneously and then comparatively rated the skiers' technical performances. Experiments differed in the required response mode only. In Exp. 1, participants made forced-choice decisions by selecting either the left or right skier as the better performer; in Exp. 2 graded judgments were made on a 10-point scale ranging from -5 (skier on the left side) to + 5 (skier on the right side). Body-specific associations were found in Exp. 1 (OR = 3.16), but not in Exp. 2 (OR = 1.50). A control experiment (Exp. 3; same participants) revealed that our sample (OR = 2.31) behaved similar to previously reported samples in a well-established cartoon character task, thereby confirming body-specific associations in our sample on a task with abstract static stimuli. Collectively, body-specific associations seem to apply to realistic dynamic scenes, particularly when frugal forced-choice decisions are required.

Goalkeepers' Reputations Bias Shot Placement in Soccer Penalties.

Research has demonstrated that in addition to minor changes in goalkeepers' position or height, goalkeeper reputation seems to influence penalty takers' shot placement. However, this evidence is based on correlative designs. Here, the authors experimentally manipulated both height and reputation to examine their causal impact on actual shot placement. Penalty takers performed kicks facing goalkeepers of different height (tall vs. short) and reputation (high vs. low) projected on a life-size screen. Results showed that tall goalkeepers were judged as taller than short goalkeepers. Likewise, high-reputation goalkeepers were judged as taller than low-reputation goalkeepers. An important finding was that reputation also influenced shot placement. When facing high-reputation goalkeepers, penalty takers aimed farther away from the goalkeeper and missed the goal more often. It follows that reputation affects both height estimates of goalkeepers and, most important, shot placement. Consequently, manipulating perceived reputation of goalkeepers provides an avenue for sport professionals to subtly influence shot placement of penalty takers.

Nothing magical: pantomimed grasping is controlled by the ventral system.

In a recent amendment to the two-visual-system model, it has been proposed that actions must result in tactile contact with the goal object for the dorsal system to become engaged (Whitwell et al., Neuropsychologia 55:41-50, 2014). The present study tested this addition by assessing the use of allocentric information in normal and pantomime actions. To this end, magicians, and participants who were inexperienced in performing pantomime actions made normal and pantomime grasps toward objects embedded in the Müller-Lyer illusion. During pantomime grasping, a grasp was made next to an object that was in full view (i.e., a displaced pantomime grasping task). The results showed that pantomime grasps took longer, were slower, and had smaller hand apertures than normal grasping. Most importantly, hand apertures were affected by the illusion during pantomime grasping but not in normal grasping, indicating that displaced pantomime grasping is based on allocentric information. This was true for participants without experience in performing pantomime grasps as well as for magicians with experience in pantomiming. The finding that the illusory bias is limited to pantomime grasping and persists with experience supports the conjecture that the normal engagement of the dorsal system's contribution requires tactile contact with a goal object. If no tactile contact is made, then movement control shifts toward the ventral system.

Vision adds to haptics when dyads perform a whole-body joint balance task.

When two or more people aim to produce joint action outcomes they need to coordinate their individual actions in space and time. Successful joint action performance has been reported to depend, among others, on visual and somatosensory information provided to the joint actors. This study investigated whether and how the systematic manipulation of visual information modulates real-time joint action when dyads performed a whole-body joint balance task. To this end, we introduced the Joint Action Board (JAB) where partners guided a ball through a maze towards a virtual hole by jointly shifting their weight on the board under three visual conditions: (1) the Follower had neither visual access to the Leader nor to the maze; (2) the Follower had no visual access to the maze but to the Leader; (3) the Follower had full visual access to both the Leader and to the maze. Joint action performance was measured as completion time of the maze task; interpersonal coordination was examined by means of kinematic analyses of both partners' motor behaviour. We predicted that systematically adding visual to the available haptic information would result in a significant increase in joint performance and that Leaders would change their coordination behavior depending on these conditions. Results showed that adding visual information to haptics led to an increase in joint action performance in a Leader-Follower relationship in a joint balance task. In addition, interpersonal coordination behavior (i.e. sway range of motion, time-lag between partner's bodies etc.) changed dependent on the provided visual information between partners in the jointly executed task.

Being (un)moved by mental time travel.

Mental imagery of events in the past or future, and of unpleasant or pleasant events, has been found to lead to spontaneous backward/forward bodily motions. Both time and emotion are represented along a spatial continuum, and activation of these representations seems to be simulated in spontaneous changes in body posture. We performed a conceptual replication and extension of an earlier study by Miles, Nind, and Macrae (2010) who reported clear postural effects when thinking of the past and the future. We additionally tested whether changes in posture appear when thinking of an emotional event. Volunteers engaged in mental imagery, involving combinations of time intervals and emotions. We simultaneously recorded center-of-pressure (COP) changes. Results revealed neither an effect of imagery of time nor of emotion on body posture. We conclude that embodied effects of imagery of abstract items on body posture may be less robust than suggested by previous literature.

Quantifying external focus of attention in sailing by means of action sport cameras.

The aim of the current study was twofold: (1) to validate the use of action sport cameras for quantifying focus of visual attention in sailing and (2) to apply this method to examine whether an external focus of attention is associated with better performance in upwind sailing. To test the validity of this novel quantification method, we first calculated the agreement between gaze location measures and head orientation measures in 13 sailors sailing upwind during training regattas using a head mounted eye tracker. The results confirmed that for measuring visual focus of attention in upwind sailing, the agreement for the two measures was high (intraclass correlation coefficient (ICC) = 0.97) and the 95% limits of agreement were acceptable (between -8.0% and 14.6%). In a next step, we quantified the focus of visual attention in sailing upwind as fast as possible by means of an action sport camera. We captured sailing performance, operationalised as boat speed in the direction of the wind, and environmental conditions using a GPS, compass and wind meter. Four trials, each lasting 1 min, were analysed for 15 sailors each, resulting in a total of 30 upwind speed trials on port tack and 30 upwind speed trials on starboard tack. The results revealed that in sailing - within constantly changing environments - the focus of attention is not a significant predictor for better upwind sailing performances. This implicates that neither external nor internal foci of attention was per se correlated with better performances. Rather, relatively large interindividual differences seem to indicate that different visual attention strategies can lead to similar performance outcomes.

Acting is perceiving!

We challenge Firestone & Scholl's (F&S's) narrow conceptualization of what perception is and - most important - what it is for. Perception guides our (inter)actions with the environment, with attention ensuring that the actor is attuned to information relevant for action. We dispute F&S's misconceived (and counterfactual) view of perception as a module that functions independently from cognition, attention, and action.

Size estimates of action-relevant space remain invariant in the face of systematic changes to postural stability and arousal.

Perceptual estimates of action-relevant space have been reported to vary dependent on postural stability and concomitant changes in arousal. These findings contribute to current theories proposing that perception may be embodied. However, systematic manipulations to postural stability have not been tested, and a causal relationship between postural stability and perceptual estimates remains to be proven. We manipulated postural stability by asking participants to stand in three differently stable postures on a force plate measuring postural sway. Participants looked at and imagined traversing wooden beams of different widths and then provided perceptual estimates of the beams' widths. They also rated their level of arousal. Manipulation checks revealed that the different postures resulted in systematic differences in body sway. This systematic variation in postural stability was accompanied by significant differences in self-reported arousal. Yet, despite systematic differences in postural stability and levels of arousal perceptual estimates of the beams' widths remained invariant.

Size estimates remain stable in the face of differences in performance outcome variability in an aiming task.

In perceptual-motor tasks such as dart throwing, those who hit the target more successfully report the target to be bigger than those who hit less successfully. While initial evidence seemed to support the recent contention that the variability in performance (rather than the amount of successful hits) may scale reported target size, here we provide counterevidence for this hypothesis. We systematically manipulated performance outcomes in a shuffling task by means of magnetic fields. Participants were asked to slide a disk on a wooden board towards a circular target. Using a within-subjects design, in two conditions throw outcomes were manipulated to produce either high or low variability in performance outcome, while the mean success of performance (i.e., the mean error) remained constant across conditions. Despite the successful manipulations of high and low variability in the performance outcomes, results revealed that size estimates of the target remained stable.

Judgement bias in predicting the success of one's own basketball free throws but not those of others.

Skilled basketball players are supposed to hit more often from the free throw distance than would be predicted by their shooting performances at adjacent distances. This is dubbed an especial skill. In the current study, we examined whether especial skills in free throw performance in basketball map onto especial skills in visually judging the success of basketball free throws. In addition, we tested whether this effect would be present in those who predict their own shots but absent in those who judge shots performed by another person. Eight skilled basketball players were coupled with eight equally skilled players, and performed 150 set shots from five different distances (including the free throw distance) while the yoked partner observed the shots. At the moment of ball release, the performers' and the observers' vision were synchronously occluded using liquid-crystal occlusion goggles, and both independently judged whether the shot was successful or not. Results did not replicate an especial skill effect in shooting performance. Based on signal detection theory (SDT) measures (d' and criterion c), results also revealed no especial skill for visually discriminating successful from unsuccessful shots at the foul line when compared to other distances. However, players showed an especial skill judgement bias towards judging balls 'in' at the foul line, but not at other distances. Importantly, this bias was only present in those who judged the success of their own shots, but not in those who judged the shots performed by someone else.

Visual search, movement behaviour and boat control during the windward mark rounding in sailing.

In search of key-performance predictors in sailing, we examined to what degree visual search, movement behaviour and boat control contribute to skilled performance while rounding the windward mark. To this end, we analysed 62 windward mark roundings sailed without opponents and 40 windward mark roundings sailed with opponents while competing in small regattas. Across conditions, results revealed that better performances were related to gazing more to the tangent point during the actual rounding. More specifically, in the condition without opponents, skilled performance was associated with gazing more outside the dinghy during the actual rounding, while in the condition with opponents, superior performance was related to gazing less outside the dinghy. With respect to movement behaviour, superior performance was associated with the release of the trimming lines close to rounding the mark. In addition, better performances were related to approaching the mark with little heel, yet heeling the boat more to the windward side when being close to the mark. Potential implications for practice are suggested for each phase of the windward mark rounding.

Dual-tasking modulates movement speed but not value-based choices during walking.

Value-based decision-making often occurs in multitasking scenarios relying on both cognitive and motor processes. Yet, laboratory experiments often isolate these processes, thereby neglecting potential interactions. This isolated approach reveals a dichotomy: the cognitive process by which reward influences decision-making is capacity-limited, whereas the influence of motor cost is free of such constraints. If true, dual-tasking should predominantly impair reward processing but not affect the impact of motor costs. To test this hypothesis, we designed a decision-making task in which participants made choices to walk toward targets for rewards while navigating past an obstacle. The motor cost to reach these rewards varied in real-time. Participants either solely performed the decision-making task, or additionally performed a secondary pitch-recall task. Results revealed that while both reward and motor costs influenced decision-making, the secondary task did not affect these factors. Instead, dual-tasking slowed down participants' walking, thereby reducing the overall reward rate. Hence, contrary to the prediction that the added cognitive demand would affect the weighing of reward or motor cost differentially, these processes seem to be maintained at the expense of slowing down the motor system. This slowdown may be indicative of interference at the locomotor level, thereby underpinning motor-cognitive interactions during decision-making.

State anticipation and task serialization attenuate embodied decision biases when deciding while moving.

We examined whether and how embodied decision biases-related to motor costs (MC) as well as cognitive crosstalk (CC) due to the body state-are influenced by extended deliberation time. Participants performed a tracking task while concurrently making reward-based decisions, with rewards being presented with varying preview time. In Experiment 1 (N = 58), we observed a reduced CC bias with extended preview time. Partially, this was due to participants slightly adapting tracking to serialize it in relation to decision making. However, the influence of MC was only marginal and not subject to anticipatory state adjustments. In Experiment 2 (N = 67), we examined whether participants integrated the immediate state at reward presentation or anticipated state when a decision could be implemented when adapting their tracking and decision behavior. Results were most compatible with the anticipated state being integrated. We conclude that humans anticipate the body state when a decision must be implemented and consider the corresponding motor and cognitive demands when adapting their decision behavior. However, anticipatory state adaptations targeting the influence of MC with extended preview time were absent, suggesting that anticipatory adaptations are starkly limited in low-practice tasks compared to more overlearned behavior like walking. (PsycInfo Database Record (c) 2024 APA, all rights reserved).