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Our timing estimates are often prone to distortions from non-temporal attributes such as the direction of motion. Motion direction has been reported to lead to interval dilation when the movement is toward (i.e., looming) as compared to away from the viewer (i.e., receding). This perceptual asymmetry has been interpreted based on the contextual salience and prioritization of looming stimuli that allows for timely reactions to approaching objects. This asymmetry has mainly been studied through abstract stimulation with minimal social relevance. Focusing on the latter, we utilized naturalistic displays of biological motion and examined the aforementioned perceptual asymmetry in the temporal domain. In Experiment 1, we tested visual looming and receding human movement at various intervals in a reproduction task and found no differences in the participants’ timing estimates as a function of motion direction. Given the superiority of audition in timing, in Experiment 2, we combined the looming and receding visual stimulation with sound stimulation of congruent, incongruent, or no direction information. The analysis showed an overestimation of the looming as compared to the receding visual stimulation when the sound presented was of congruent or no direction, while no such difference was noted for the incongruent condition. Both looming and receding conditions (congruent and control) led to underestimations as compared to the physical durations tested. Thus, the asymmetry obtained could be attributed to the potential perceptual negligibility of the receding stimuli instead of the often-reported salience of looming motion. The results are also discussed in terms of the optimality of sound in the temporal domain.

It has been argued that movement can be implied by static cues of images depicting an instance of a dynamic event. Instances of implied motion have been investigated as a special type of stimulus with common processing mechanisms to those of real motion. Timing studies have reported a lengthening of the perceived time for moving as opposed to static stimuli and for stimuli of higher as compared to lower amounts of implied motion. However, the actual comparison of real versus implied motion on timing has never been investigated. In the present study, we compared directly the effect of two hypothetically analogous ballet steps with different amounts of movement and static instances of the dynamic peak of these events in a reproduction task. The analysis revealed an overestimation and lower response variability for real as compared to implied motion stimuli. These findings replicate and extend the apparent duration lengthening for moving as compared to static stimulation, even for static images containing implied motion, questioning whether or not the previously reported correspondence between real and implied motion transfers in the timing domain. This lack of correspondence was further supported by the finding that the amount of movement presented affected only displays of real motion.

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Speed has been proposed as a modulating factor on duration estimation. However, the different measurement methodologies and experimental designs used have led to inconsistent results across studies, and, thus, the issue of how speed modulates time estimation remains unresolved. Additionally, no studies have looked into the role of spatiotemporal experience and susceptibility to modulations of speed in timing judgments. In the present study, therefore, using naturalistic, dynamic dance stimuli, we aimed at defining the role of speed and the interaction of speed and experience on time estimation. We presented videos of a dancer performing identical ballet steps in fast and slow versions, while controlling for the number of changes present. Professional dancers and non-dancers performed duration judgments through a production and reproduction task. Analysis revealed a significantly larger underestimation of fast videos as compared to slow ones during reproduction. The exact opposite result was true for the production task. Dancers were generally more accurate and significantly less variable in their time estimations as compared to non-dancers. Speed and experience, therefore, affect participants’ estimates of time. Results are discussed in association to the theoretical framework of current models by focusing on the role of attention.

We report two experiments aiming to define how experience and stimulus enactment affect multisensory temporal integration for ecologically-valid stimuli. In both experiments, a number of different dance steps were used as audiovisual displays at a range of stimulus onset asynchronies using the method of constant stimuli. Participants were either professional dancers or non-dancers. In Experiment 1, using a simultaneity judgment (SJ) task, we aimed at defining — for the first time — the temporal window of integration (TWI) for dancers and non-dancers and the role of experience in SJ performance. Preliminary results showed that dancers had smaller TWI in comparison to non-dancers for all stimuli tested, with higher complexity (participant rated) dance steps requiring larger auditory leads for both participant groups. In Experiment 2, we adapted a more embodied point of view by examining how enactment of the stimulus modulates the TWIs. Participants were presented with simple audiovisual dance steps that could be synchronous or asynchronous and were asked to synchronize with the audiovisual display by actually performing the step indicated. A motion capture system recorded their performance at a millisecond level of accuracy. Based on the optimal integration hypothesis, we are currently looking at the data in terms of which modality will be dominant, considering that dance is a spatially (visual) and temporally (audio) coordinated action. Any corrective adjustments, accelerations–decelerations, hesitations will be interpreted as indicators of the perception of ambiguity in comparison to their performance at the synchronous condition, thus, for the first time, an implicit SJ response will be measured.