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Project

Visual perception of actions: The influence of time structure

Working groupRealistic Depictions Lab
Duration11/2013 - 12/2020
Funding

IWM Budget resources

Project description

Observing visual activities in everyday life, people do not process them as continuously streaming events, but tend to segment the stream of events in meaningful segments and even to order them hierarchically. This influences not only our everyday perception of real-life surrounding us. Also, presentation of events in visual media like film and video clips base on these principles. For example, video clips make temporal ellipses, i.e., skip cutouts in the flow of actions. Doing this, a clip can present the same temporal content, but can shorten the presentation time needed to show the event. The project examined the influence of the temporal duration of filmic ellipses (1) on the perceived duration of events, and (2) on the hierarchical level on which observers process an event. Therefor several everyday actions of lay persons were filmed, and different film versions presented each action with either long or short skips in time, i.e, with either short or long filmic ellipses.


In everyday life, when observing activities taking place in our environment, we often shift our attention among several activities and therefore perceive each activity sequence piecemeal with temporal gaps in between. Two studies examined whether the length of these gaps influences the processing of the observed activities. Experiment 1 presented film clips depicting activities that were interrupted by either short or long gaps and asked participants to estimate how long the target action presented at the end of the clip would normally take if it were to take place in reality. Using the same activities, Experiment 2 asked participants to judge the duration of the presentation of this target action—that is, how long the target action was presented. Results showed that following long gaps instead of short gaps, target actions are estimated to take longer in reality (Experiment 1), but the depictions themselves are estimated to be shorter (Experiment 2). Following long gaps, target actions seem to be processed pars pro toto as placeholders for longer segments in the stream of events, but in contrast, the depictions themselves appear to be shorter. Results suggest that long gaps lengthen the perceived duration of an event in our cognitive representation, and also seem to influence our perception of the duration of the presentation itself.

Events and activities do not only consist of a sequence of individual actions but also form a hierarchy, with chains of low-level actions being grouped together to higher-level activities. Therefore, observers face the task of not only segmenting a continuous event stream into discrete units but also processing these units on an appropriate level of aggregation. In two experiments, we show that for events observed in an incomplete, piecemeal manner, the temporal extension of event gaps influences the level of hierarchy on which an observer processes the presented event (Experiment 1) and that the level of hierarchy is also transferred to an anticipated subsequent event (Experiment 2). Film clips presented everyday activities with short or long gaps in time between the successive shots that presented parts of the same activity. The viewers´ level of processing was captured via the cued recall of the participants describing what they had seen in the film clip or via their formulations used when describing what they expected to happen next. Our findings suggest an extended model of event cognition: Viewers aim to represent events continuously and therefore extrapolate in case of gaps by shifting to higher levels of descriptions.


Publications

Garsoffky, B., & Schwan, S. (2020). Same action, different level: Descriptions of perceived or predicted actions depend on preceding temporal gaps in event streams. Journal of Experimental Psychology: Learning, Memory, and Cognition, 46(10), 1868-1880. https://dx.doi.org/10.1037/xlm0000855 request document
 

Garsoffky, B., Huff, M., & Schwan, S. (2017). Mind the gap: Temporal discontinuities in observed activity streams influence perceived duration of actions. Psychonomic Bulletin & Review, 24, 1627-1635. https://dx.doi.org/10.3758/s13423-017-1239-2 [Data] request document