<p>Successful navigation requires an accurate mental spatial representation of the environment that can be updated during movement. Experiments with animals and humans have demonstrated the existence of two forms of spatial representation: egocentric (observer-centered) and allocentric (environment-centered). Unfortunately, specifically how humans use these two systems is not well understood. The current dissertation was focused on providing evidence differentiating human use of egocentric and allocentric spatial reference frames, specifically examining the characteristics and contributions from body-based sources. Two empirical chapters are presented that include experiments involving two common spatial tasks. In Chapter 2, updating of feature relations within a room-sized environment was examined by having observers provide directional judgments to learned features with respect to an imagined orientation that was either congruent or incongruent with their physical orientation. The information available for updating the physical orientation was manipulated across experiments. Performance differences between congruent and incongruent conditions demonstrated the reliance on egocentric representations for updating, and differentiated body- and knowledge-based components of the egocentric updating process. The specificity of the body-based component was examined in Chapter 3 by having observers detect changes made to a tabletop spatial scene following a viewpoint shift resulting from their movement, scene rotation or both. The relation between the extent of observer movement and the magnitude of the experienced viewpoint shift was manipulated. Change detection performance was best when the extent of observer movement most closely matched the viewpoint shift, and declined as the match declined. Thus, body-based cues contributed specific information for updating self-to-feature relations that facilitated scene recognition. Throughout the course of the research program it has become clear that humans rely on egocentric representations to complete these tasks, and sensory and motor modalities involved in self-motion are integrated for updating spatial relations of novel environments.</p> / Doctor of Philosophy (PhD)

Das Ziel der Dissertation ist, den Gebrauch von sekundären Raumdeixes (‚vor‘, ‚hinter‘, ‚rechts / links von‘) und Referenzrahmen (absolut, intrinsisch, relativ) von deutschen, englischen, italienischen und polnischen Muttersparcher_innen für die Beschreibung von statischen Raumrelationen zu untersuchen. Zwei Experimente pro Sprache wurden durchgeführt. Das erste Experiment untersuchte Seitenzuweisung. Die Proband_innen sahen ein Objekt von der Vorderseite (kanonische Position) und Rückseite (nicht-kanonische Position). Das Ergebnis bestätigt, dass die Proband_innen der vier Sprachen die Außenperspektive für die Seitenzuweisung des kanonisch stehenden vis-à-vis Objektes meistens benutzen. Einige Variationen haben die Pol_innen und Italiener_innen gezeigt, vor allem bei der Zuweisung von der rechten und linken Seite. Dabei wiesen die Deutschen und Italiener_innen signifikante Unterschiede auf. Mit dem Mouse Tracking habe ich die Interpretation von statischen Raumrelationen von zwei Komplexitätsgraden untersucht. Die einfachen Raumrelationen enthielten entweder ein extrinsisches oder intrinsisches Referenzobjekt (belebt; unbelebt) und eine Flasche als lokalisiertes Objekt. Die komplexeren Raumrelationen wurden um einen Agenten ergänzt und mit der indirekten Rede eingebettet. Das erlaubte die Erforschung von Origo-Shift. In allen Raumrelationen wurden die Proband_innen gebeten, die Lokalisation von der Flasche zu beschreiben. Die Deutschen und Italiener_innen zeigten signifikante Unterschiede bei der Interpretation von einfachen belebten und unbelebten intrinsischen Raumrelationen. Bei der Interpretation von komplexeren intrinsischen Raumrelationen haben die polnischen Muttersprachler_innen die Origo am häufigsten zum Agenten verschoben und von seinem Blickwinkel bezüglich des relativen Bezugsrahmens die Relationen beschrieben. Im Allgemeinen, für die Interpretation von komplexeren Raumrelationen ist die Wahl des intrinsischen Bezugsrahmens im Vergleich zu einfacheren Raumrelationen signifikant gesunken. Das heißt, die meisten Proband_innen haben die Origo zum Agenten verschoben und von seinem Blickwinkel die Raumrelationen bezüglich der Spiegelstrategie interpretiert. / The aim of this dissertation is to investigate the use of reference frames (absolute, relative, intrinsic) and secondary local deixes (‘in front of’, ‘behind’, ‘to the right / left of’) by German, English, Italian, and Polish native speakers to describe static spatial relations. Two experiments per language were carried out. The first experiment investigated side assignment. Participants saw the object from the front (the canonical position) and the back (the noncanonical position). The results confirm that for side assignments to a canonical positioned vis-à-vis object most speakers of the four languages use the outside perspective. However, some variations occurred for Polish and Italian, especially while identifying the right and left sides showing significant differences between German and Italian. Using mouse tracking, I tested the interpretation of static spatial relations of two kinds of complexity. The simple spatial relations included either extrinsic or intrinsic reference objects (animate; inanimate) and a bottle as localized object. The complex spatial relations were supplemented by an agent and embedded by indirect speech. This allows the investigation of origo shift. In all situations, participants were asked to describe the location of the bottle. German and Italian showed significant differences in interpreting simple animate and inanimate intrinsic relations. Interpreting the intrinsic complex relations, Polish speakers shifted the origo to the agent most frequently and described the relations from his point of view. All in all, for the complex relations, the choice of the intrinsic reference frame decreased significantly compared to the simple relations. That is, most participants shifted the origo to agents’ point of view and interpreted the spatial relations applying the reflection strategy.