Imagined Headings Research Articles

Mental representations of recently learned nested environments.

Two experiments investigated the mental representations of objects' location in a virtual nested environment. In Experiment 1, participants learned the locations of objects (buildings or related accessories) in an exterior environment and then learned the locations of objects inside one of the centrally located buildings (interior environment). Participants completed judgments of relative direction in which the imagined heading was established by pairs of objects from the interior environment and the target was one of the objects in the exterior environment. Performance was best for the imagined heading and allocentric target direction parallel to the learning heading of the exterior environment, but the effect of allocentric target direction was only significant for the imagined headings aligned with the reference axes of both environments; in addition, performance was best along the front-back egocentric axis (parallel to the imagined heading). Experiment 2 used the same learning procedure. After learning, the viewpoint was moved from the exterior environment along a smooth path into a side entrance of the building/interior environment. There participants saw the array of interior objects in the orientation consistent with their movement (correct cue), the array of objects in an orientation inconsistent with their movement (misleading cue), or no array of objects (no cue), and then pointed to objects in the exterior environment. Pointing performance was best for the correct-cue condition. Collectively the results indicated that memories of nested spaces are segregated by spatial conceptual level, and that spatial relations between levels are specified in terms of the dominant reference directions.

Global frames of reference organize configural knowledge of paths

Five experiments examined the organization of spatial memory of an irregular path learned by walking with vision. Two hypotheses were tested: (a) that participants would establish a single global frame of reference to organize the spatial memory of the path; or alternatively (b) that participants would establish path-aligned reference directions at each path leg but not establish a global frame of reference. Participants donned a head-mounted display and were asked to navigate through a virtual six-segment path with each turning point indicated by a virtual object. The six legs consisted of two groups of three legs. The legs within groups were aligned (parallel or orthogonal) with each other and between groups were misaligned (45° tilted) with each other. At each leg, participants only perceived the object at the end of this leg. After participants walked the legs 10 times they conducted judgments of relative directions (JRD, e.g. “imagine you are standing at X, facing Y, please point to Z”). The imagined headings in JRD were parallel to the experienced path legs. The paths varied in terms of the salience of the longest leg. Appearance of a room was also manipulated to highlight one group of the legs. The results showed that participants demonstrated significantly lower pointing error for (a) the longest leg when there was no room or (b) the first walking leg when there was no obvious longest leg or the longest leg was misaligned with the room. Pointing error was equivalent for the longest leg and the first walking leg when the longest leg was salient and misaligned with the first walking leg. These results suggested that participants established a single global frame of reference when there was a single salient context cue. However, two oblique reference frames can be established when there are two inconsistent contextual cues.

Representations of interobject spatial relations in long-term memory

A growing body of evidence has indicated that human spatial memory is organized in terms of a small number of reference directions and that interobject spatial relations are represented in terms of these directions (e.g., McNamara, 2003). The goal of the present experiments was to investigate whether the selection of reference directions also affects the fidelity with which interobject spatial relations are represented in memory. In two experiments, participants memorized a layout of nine objects and then performed judgments of relative direction (e.g., "Imagine you are standing at the clock, facing the book. Point to the phone.") at a remote location. Imagined heading (e.g., at the clock, facing the book) and allocentric target direction (e.g., the direction from clock to phone in the allocentric frame of reference used to define imagined heading) were manipulated independently. The results of both experiments showed that the same directions that were benefited in imagined headings were also benefited in allocentric target directions. These findings indicate that interobject spatial relations are preferentially represented when they coincide with a reference direction.

Frame of Reference in the Mental Representation of Objects Layout

Frame of Reference in the Mental Representation of Objects Layout

Body- and environmental-stabilized processing of spatial knowledge.

In 5 experiments, the authors examined the perceptual and cognitive processes used to track the locations of objects during locomotion. Participants learned locations of 9 objects on the outer part of a turntable from a single viewpoint while standing in the middle of the turntable. They subsequently pointed to objects while facing the learning heading and a new heading, using imagined headings that corresponded to their current actual body heading and the other actual heading. Participants in 4 experiments were asked to imagine that the objects moved with them as they turned and were shown or only told that the objects would move with them; in Experiment 5, participants were shown that objects could move with them but were asked to ignore this as they turned. Results showed that participants tracked object locations as though the objects moved with them when shown but not when told about the consequences of their locomotion. Once activated, this processing mode could not be suppressed by instructions. Results indicated that people process object locations in a body- or an environment-stabilized manner during locomotion, depending on the perceptual consequences of locomotion.

Layout geometry in the selection of intrinsic frames of reference from multiple viewpoints.

Four experiments investigated the roles of layout geometry in the selection of intrinsic frames of reference in spatial memory. Participants learned the locations of objects in a room from 2 or 3 viewing perspectives. One view corresponded to the axis of bilateral symmetry of the layout, and the other view(s) was (were) nonorthogonal to the axis of bilateral symmetry. Judgments of relative direction using spatial memory were quicker for imagined headings parallel to the symmetric axis than for those parallel to the other viewing perspectives. This advantage disappeared when the symmetric axis was eliminated. Moreover, there was more consistency across participants in the selection of intrinsic axes when the layout contained an axis of bilateral symmetry than when it did not. These results indicate that the layout geometry affects the selection of intrinsic frames of reference supporting the intrinsic model of spatial memory proposed by W. Mou and T. P. McNamara (2002) and by A. L. Shelton and T. P. McNamara (2001).

Updating imagined translational movements

The aim of this study was to examine the mental processes involved in changes that are the result of imagined translational movements. Participants were presented with a single view of a small spatial display. In a computer-based reaction-time task, spatial judgments were then made relative to four imagined headings that were either the study view or novel views that differed from the study view in terms of imagined rotational and/or translational movements. The main finding was that translational shifts detrimentally affected performance in the absence of concurrent rotations suggesting that imagined translations require additional processing time.

Orientation dependent mental representations following real‐world navigation

The purpose of this study was to examine whether the mental representations acquired from real-world navigation are encoded in a single, specific orientation. Previous research has revealed an inconsistent pattern of results. In the present study, participants explored a university campus. In two reaction-time tasks, spatial judgments were then made relative to four imagined headings within the explored environment. The main result was that one of the headings was encoded in a distinct manner: When making left-right judgments performance on this heading was generally superior by comparison with the other orientations, and when making front-back judgments the same heading was the only one in which an advantage of front over back responses was observed. The finding that the headings were not encoded equally indicates that real-world navigation can lead to orientation specific representations.

Egocentric and geocentric frames of reference in memory of large-scale space.

This experiment investigated the frames of reference used in memory to represent the spatial structure of a large-scale outdoor environment. Participants learned the locations of eight objects in an unfamiliar city park by walking through the park on one of two prescribed paths that encircled a large rectangular building. The aligned path was oriented with the building; the misaligned path was rotated by 45 degrees. Later, participants pointed to target objects from imagined vantage points using their memories. Pointing accuracy was higher in the aligned than in the misaligned path group, and the patterns of results differed: In the aligned condition, accuracy was higher for imagined headings parallel to legs of the path and for an imagined heading oriented toward a nearby lake, a salient landmark. In the misaligned condition, pointing accuracy was highest for the imagined heading oriented toward the lake, and decreased monotonically with angular distance. These results indicated that locations of objects were mentally represented in terms of frames of reference defined by the environment but selected on the basis of egocentric experience.

Intrinsic frames of reference in spatial memory.

Three experiments investigated the frames of reference used in memory to represent the spatial structure of the environment. Participants learned the locations of objects in a room according to an intrinsic axis of the configuration; the axis was different from or the same as their viewing perspective. Judgments of relative direction using memory were most accurate for imagined headings parallel to the intrinsic axis, even when it differed from the viewing perspective, and there was no cost to learning the layout according to a nonegocentric axis. When the shape of the layout was bilaterally symmetric relative to the intrinsic axis of learning, novel headings orthogonal to that axis were retrieved more accurately than were other novel headings. These results indicate that spatial memories are defined with respect to intrinsic frames of reference, which are selected on the basis of egocentric experience and environmental cues.

Systems of Spatial Reference in Human Memory

Seven experiments examined the spatial reference systems used in memory to represent the locations of objects in the environment. Participants learned the locations of common objects in a room and then made judgments of relative direction using their memories of the layout (e.g., “Imagine you are standing at the shoe, facing the lamp; point to the clock”). The experiments manipulated the number of views that observers were allowed to experience, the presence or absence of local and global reference systems (e.g., a rectangular mat on which objects were placed and the walls of the room, respectively), and the congruence of local and global reference systems. Judgments of relative direction were more accurate for imagined headings parallel to study views than for imagined headings parallel to novel views, even with up to three study views. However, study views misaligned with salient reference systems in the environment were not strongly represented if they were experienced in the context of aligned views. Novel views aligned with a local reference system were, under certain conditions, easier to imagine than were novel views misaligned with the local reference system. We propose that learning and remembering the spatial structure of the surrounding environment involves interpreting the layout in terms of a spatial reference system. This reference system is imposed on the environment but defined by egocentric experience.