Julia Frankenstein

Is the Map in Our Head Oriented North

We examined how a highly familiar environmental space—one’s city of residence—is represented in memory. Twenty-six participants faced a photo-realistic virtual model of their hometown and completed a task in which they pointed to familiar target locations from various orientations. Each participant’s performance was most accurate when he or she was facing north, and errors increased as participants’ deviation from a north-facing orientation increased. Pointing errors and latencies were not related to the distance between participants’ initial locations and the target locations. Our results are inconsistent with accounts of orientation-free memory and with theories assuming that the storage of spatial knowledge depends on local reference frames. Although participants recognized familiar local views in their initial locations, their strategy for pointing relied on a single, north-oriented reference frame that was likely acquired from maps rather than experience from daily exploration. Even though participants had spent significantly more time navigating the city than looking at maps, their pointing behavior seemed to rely on a north-oriented mental map.

The language of landmarks: the role of background knowledge in indoor wayfinding

To effectively wayfind through unfamiliar buildings, humans infer their relative position to target locations not only by interpreting geometric layouts, especially length of line of sight, but also by using background knowledge to evaluate landmarks with respect to their probable spatial relation to a target. Questionnaire results revealed that participants have consistent background knowledge about the relative position of target locations. Landmarks were rated significantly differently with respect to their spatial relation to targets. In addition, results from a forced-choice task comparing snapshots of a virtual environment revealed that background knowledge influenced wayfinding decisions. We suggest that landmarks are interpreted semantically with respect to their function and spatial relation to the target location and thereby influence wayfinding decisions. This indicates that background knowledge plays a role in wayfinding.

Reference frames in learning from maps and navigation

In everyday life, navigators often consult a map before they navigate to a destination (e.g., a hotel, a room, etc.). However, not much is known about how humans gain spatial knowledge from seeing a map and direct navigation together. In the present experiments, participants learned a simple multiple corridor space either from a map only, only from walking through the virtual environment, first from the map and then from navigation, or first from navigation and then from the map. Afterwards, they conducted a pointing task from multiple body orientations to infer the underlying reference frames. We constructed the learning experiences in a way such that map-only learning and navigation-only learning triggered spatial memory organized along different reference frame orientations. When learning from maps before and during navigation, participants employed a map- rather than a navigation-based reference frame in the subsequent pointing task. Consequently, maps caused the employment of a map-oriented reference frame found in memory for highly familiar urban environments ruling out explanations from environmental structure or north preference. When learning from navigation first and then from the map, the pattern of results reversed and participants employed a navigation-based reference frame. The priority of learning order suggests that despite considerable difference between map and navigation learning participants did not use the more salient or in general more useful information, but relied on the reference frame established first.

Configurational salience of landmarks: an analysis of sketch maps using Space Syntax

Abstract We conducted a visibility graph analysis (a Space Syntax method) of a virtual environment to examine how the configurational salience of global and local landmarks (i.e., their relative positions in the environment) as compared to their visual salience affects the probability of their depiction on sketch maps. Participants of two experimental conditions produced sketch maps from memory after exploration with a layout map or without a map, respectively. Participants of a third condition produced sketch maps in parallel to exploration. More detailed sketch maps were produced in the third condition, but landmarks with higher configurational salience were depicted more frequently across all experimental conditions. Whereas the inclusion of global landmarks onto sketch maps was best predicted by their size, both visual salience and isovist size (i.e., the area a landmark was visible from) predicted the frequency of depiction for local landmarks. Our findings imply that people determine the relevance of landmarks not only by their visual, but even more by their configurational salience.

When in doubt follow your nose: a wayfinding strategy

Route selection is governed by various strategies which often allow minimizing the required memory capacity. Previous research showed that navigators primarily remember information at route decision points and at route turns, rather than at intersections which required straight walking. However, when actually navigating the route or indicating directional decisions, navigators make fewer errors when they are required to walk straight. This tradeoff between location memory and route decisions accuracy was interpreted as a “when in doubt follow your nose” strategy which allows navigators to only memorize turns and walk straight by default, thus considerably reducing the number of intersections to memorize. These findings were based on newly learned routes. In the present study, we show that such an asymmetry in route memory also prevails for planning routes within highly familiar environments. Participants planned route sequences between locations in their city of residency by pressing arrow keys on a keyboard. They tended to ignore straight walking intersections, but they ignored turns much less so. However, for reported intersections participants were quicker at indicating straight walking than turning. Together with results described in the literature, these findings suggest that a “when in doubt follow your nose strategy” is applied also within highly familiar spaces and might originate from limited working memory capacity during planning a route.

Not all memories are the same: Situational context influences spatial recall within one's city of residency.

Reference frames in spatial memory encoding have been examined intensively in recent years. However, their importance for recall has received considerably less attention. In the present study, passersby used tags to arrange a configuration map of prominent city center landmarks. It has been shown that such configurational knowledge is memorized within a north-up reference frame. However, participants adjusted their maps according to their body orientations. For example, when participants faced south, the maps were likely to face south-up. Participants also constructed maps along their location perspective—that is, the self–target direction. If, for instance, they were east of the represented area, their maps were oriented west-up. If the location perspective and body orientation were in opposite directions (i.e., if participants faced away from the city center), participants relied on location perspective. The results indicate that reference frames in spatial recall depend on the current situation rather than on the organization in long-term memory. These results cannot be explained by activation spread within a view graph, which had been used to explain similar results in the recall of city plazas. However, the results are consistent with forming and transforming a spatial image of nonvisible city locations from the current location. Furthermore, prior research has almost exclusively focused on body- and environment-based reference frames. The strong influence of location perspective in an everyday navigational context indicates that such a reference frame should be considered more often when examining human spatial cognition.

Global landmarks do not necessarily improve spatial performance in addition to bodily self-movement cues when learning a large-scale virtual environment

Comparing spatial performance in different virtual reality setups can indicate which cues are relevant for a realistic virtual experience. Bodily self-movement cues and global orientation information were shown to increase spatial performance compared with local visual cues only. We tested the combined impact of bodily and global orientation cues by having participants learn a virtual multi corridor environment either by only walking through it, with additional distant landmarks providing heading information, or with a surrounding hall relative to which participants could determine their orientation and location. Subsequent measures on spatial memory only revealed small and non-reliable differences between the learning conditions. We conclude that additional global landmark information does not necessarily improve users orientation within a virtual environment when bodily-self-movement cues are available.

The situational influence of location and body orientation on the recall of survey knowledge

Poster presentations (in alphabetical order, according to the first authors’ last names) Video game play changes spatial and verbal memory: rehabilitation of a single case with traumatic brain