Mechanisms of object-based correspondence (DFG HE7543/1-1; Elisabeth Hein)
The visual system is able to create and maintain a stable representation of our environment - keeping the identity of the elements around us through changes in space over time - despite the original information that arrives at the retina being ambiguous. For a long time, the dominant view in the field was that the visual system is able to do so, i.e., to establish correspondence between elements, using mainly spatiotemporal proximity that in turn determines motion energy between the elements. Recent studies, however, showed that higher-level factors, e.g., the perceived feature similarity between the elements and the grouping context, could also play an important role in determining correspondence. The aim of this project is to use behavioral experiments, as well as eye tracking and electrophysiological measurements, in order to test specific predictions of a new object-based correspondence mechanism. This mechanism is able to account for the new results and explain the influence of higher-level factors through a correspondence process that is based on object representations instead of basic low-level factors as spatiotemporal proximity. In particular, this project will examine the influence of attention on correspondence, determine the level at which the processing of correspondence is solved, and assess the role that the scene and feature variability of the context play in correspondence.
Mechanisms of temporal preparation in stimulus selection (DFG SE2576/1-1; Verena Seibold)
Selective attention is a fundamental mechanism of the brain that allows selecting only that part of incoming sensory information for deeper processing that is currently relevant and matches the needs and goals of an organism. Recent research work suggests that the efficiency of this selection mechanism depends fundamentally on an organism’s ability to make temporal predictions and thus temporally prepare the brain for sensory information. Yet, it is still unclear how temporal preparation for sensory information exerts its beneficial effect on stimulus selection. The aim of this project is to fill in this gap and to investigate systematically the mechanisms by which temporal preparation facilitates stimulus selection.