Motor performance in joint action tasks: The impact of dyadic motive fit.

In many daily situations, two or more individuals need to coordinate their actions to achieve a common goal and perform successfully. Past research on joint action has predominantly focused on the question of how such interactions are accomplished. Here we focus on the impact of inter-individual, trait-like differences to predict joint action performance. More specifically, we examined whether performance in a joint action task is moderated by the (in)congruence of individuals' motive dispositions. To this end, 27 dyads performed a joint action task in which they had to navigate a ball through a maze with each partner using a joystick and each being responsible for either moving the ball along the x-axis or the y-axis. As dependent measures, we analyzed dyads' performance (times and errors). As trait-like predictors, we assessed implicit and explicit motives by means of the Picture Story Exercise and the Unified Motive Scale, respectively. Linear regression modeling revealed that congruent explicit affiliation motives predict faster best times and that higher congruent implicit achievement motives are associated with reduced errors. Exploratory Response Surface Analyses yielded identical results for the affiliation motive. These findings provide initial evidence to suggest that interindividual differences and in motives as well as their fit are related to joint action performance. Future directions of this new paradigm and novel ways to analyze dyadic motive fits and their relation to joint action performance are discussed.

Slow motion bias: Exploring the relation between time overestimation and increased perceived intentionality.

Recent research on time perception has revealed that actions which are replayed in slow motion are perceived to take longer and rated to be more intentional (e.g., foul plays). Interestingly, the bias on duration estimations seems to disappear when information on the slow motion factor (i.e., the degree the video was slowed down) was provided. Here, we scrutinize the question whether also the intentionality bias disappears when explicit information about the slow motion factor is provided. To this end, two groups watched the same video clips, all displaying foul situations in a basketball match, in different video speeds. While the uninformed group saw the videos without further information, the informed group received additional information about the current slow motion factor. This study replicated the overestimation of original duration with increasing slow motion and indicated that this effect might be reduced when information about the slow motion factor is provided. However, despite generally lower intentionality ratings in the informed group, video speed information was not able to reduce the rise in intentionality ratings with increasing slow motion. Potential reasons and open questions regarding the nature and mechanisms behind these perceptual temporal biases (e.g., different time processing systems) are discussed.

Why Do Actions in Slow Motion Appear to Last Longer? On the Effect of Video Speed Information.

When displayed in slow motion, actions are often perceived longer compared with original speed. However, it remains to be determined why this bias exists. Is it possible that the bias emerges because participants underestimate the factor by which a video was slowed down and hence arrive at erroneous conclusions about the original duration? If true, providing explicit information about the respective video speed should eliminate this slow motion effect. To scrutinize the nature of this bias, participants rated the original duration of sports actions displayed at original speed or slow motion. Results revealed the expected overestimation bias consisting in longer ratings with increasing slow motion. However, the bias disappeared when information about the current video speed was provided. The observations suggest an influence of knowledge about video playback speed on cognitive-evaluative processes which may hold important implications for future research and practice.