Failure to demonstrate short-cutting in a replication and extension of Tolman et al.'s spatial learning experiment with humans.

Successful demonstrations of novel short-cut taking by animals, including humans, are open to interpretation in terms of learning that is not necessarily spatial. A classic example is that of Tolman, Ritchie, and Kalish (1946) who allowed rats to repeat a sequence of turns through the corridors of a maze to locate a food reward. When the entrance to the corridors was subsequently blocked and alternative corridors were made available, rats successfully selected the corridor leading most directly to the food location. However, the presence of a distinctive light above the goal, in both the training and testing phases, means that approach to the light as a beacon could have been the source of successful short-cutting. We report a replication of the experimental design of Tolman et al. with human participants who explored geometrically equivalent virtual environments. An experimental group, who followed the original procedure in the absence of any distinctive cues proximal to the goal, did not select the corridor which led most directly to the goal. A control group, who experienced a light above the goal during training and testing, were more likely to select a corridor which led in the direction of the goal. A second control group experienced the light above the goal during training, but in the test the location of this cue was shifted by 90° with respect to the start point of exploration. This latter group responded unsystematically in the test, neither selecting a corridor leading to the original goal location, nor one leading directly to the relocated light cue. The results do not support the hypothesis that travelling a multi-path route automatically leads to an integrated cognitive representation of that route. The data offer support for the importance of local cues which can serve as beacons to indicate the location of a goal.

The first-perspective alignment effect: the role of environmental complexity and familiarity with surroundings.

People often remember relatively novel environments from the first perspective encountered or the first direction of travel. This initial perspective can determine a preferred orientation that facilitates the efficiency of spatial judgements at multiple recalled locations. The present study examined this "first-perspective alignment effect" (FPA effect). In three experiments, university students explored three-path routes through computer-simulated spaces presented on a desktop computer screen. Spatial memory was then tested employing a "judgement of relative direction" task. Contrary to the predictions of a previous account, Experiment 1 found a reliable FPA effect in barren and complex environments. Experiment 2 strongly implicated the importance of complete novelty of the space surrounding the route in producing the effect. Experiment 3 found that, while familiarity with the surrounding space greatly attenuated the FPA effect with immediate testing, the effect reemerged following a 7-day delay to testing. The implications for the encoding and retrieval of spatial reference frames are discussed.

Enclosure shape influences cue competition effects and goal location learning.

In virtual-environment spatial-learning procedures, Experiment 1 investigated blocking of learning about distal landmarks beyond the walls of an enclosure following preliminary training to find a goal using local landmarks within the enclosure. Separate sets of blocking and control groups searched within enclosures that, in plan view, formed either a square or a circle. Blocking was apparent when training and testing occurred in the circular but not the square enclosure. In Experiment 2, preliminary training to find a goal using local landmarks blocked spatial learning based on a circular enclosure divided into four differently coloured sections. The results are discussed in relation to theories of incidental versus error-correcting learning linked to different types of spatial cue.

Blocking of goal-location learning based on shape.

Using desktop, computer-simulated virtual environments (VEs), the authors conducted 5 experiments to investigate blocking of learning about a goal location based on Shape B as a consequence of preliminary training to locate that goal using Shape A. The shapes were large 2-dimensional horizontal figures on the ground. Blocking of spatial learning was found when the initially trained Shape A was presented in the context of auxiliary shapes that were anticipated to be irrelevant to goal localization. When Shape A was initially presented in the absence of these auxiliary shapes, no evidence of blocking between shapes was apparent. The results are discussed in terms of the similarity between spatial and other forms of contingency learning, the operation of a specialized geometric module, and changes in attention as a consequence of discrimination learning.

Blocking of spatial learning between enclosure geometry and a local landmark.

In a virtual environment, blocking of spatial learning to locate an invisible target was found reciprocally between a distinctively shaped enclosure and a local landmark within its walls. The blocking effect was significantly stronger when the shape of the enclosure rather than the landmark served as the blocking cue. However, the extent to which the landmark blocked enclosure-shape learning was not influenced by increasing the physical salience of the landmark. The outcomes are the first to suggest that cue-interaction effects, commonly found in human and animal contingency learning experiments, are also found in human spatial learning based on landmarks and enclosure walls. The data are discussed in terms of spatial reference frames.

Influences on the first-perspective alignment effect from text route descriptions.

Four experiments investigated the more efficient recall of routes learned from text descriptions when the imagined orientation at test was in alignment with the first experienced perspective. Experiments 1 and 2 replicated the effect, but found little evidence for the influence of an external frame of reference provided either by describing a salient landmark external to the route, or by employing cardinal directions in the descriptions. In Experiment 3, the first-perspective alignment (FPA) effect was relatively unaffected by elaboration of spatial information or more experience of reading the text. Experiment 4 found attenuation of the FPA effect when participants made active spatial judgements from imagined key locations while learning. The results are discussed in relation to theories of spatial reference frames and the influence of location salience.

First-perspective spatial alignment effects from real-world exploration.

When spatial knowledge is acquired from secondary-learning media, such as text, people sometimes remember a route in alignment with the first perspective or first direction of travel. However, this first-perspective alignment (FPA) effect has been found only under special circumstances from primary real-world exploration. In Experiment 1, recall of an enclosed small-scale, U-shaped route was compared following learning from a verbal description, a video recording, or real-world exploration; an FPA effect was found in all cases. In Experiments 2 and 3, exploration of physically larger real routes led to statistically significant evidence of an FPA effect when the route was enclosed, but not when cues external to the route were available. The data are discussed in relation to current theories of spatial reference frames.

Memory for targets in a multi-level simulated-environment: a comparison between able-bodied and physically disabled children.

Two groups of children, one able-bodied and the other with physical disabilities, explored a symmetrical three-tiered virtual building that contained six distinctive target objects, two on each story. In a subsequent test, the target objects were removed and participants were asked to make judgments of the directions to the former target locations from each floor in turn. At each test site, judgments were required for targets that were formerly on the same floor and for those on higher and lower floors. Relative tilt error scores suggested a bias for both groups, in that targets that were higher than the test location were judged as consistently lower than their actual position, whereas targets that were lower than the test location were judged as higher than their actual position. Absolute tilt errors revealed an asymmetry in both groups, with more accurate tilt errors for judgments directed to lower than higher floors. The relevance of these results for the source of the asymmetry is discussed.

Memory for targets in a multilevel simulated environment: evidence for vertical asymmetry in spatial memory.

In two experiments, adult participants explored a symmetrical three-tiered computer-simulated building that contained six distinctive objects, two on each floor. Following exploration, the objects were removed, and the participants were asked to make direction judgments from each floor, indicating the former positions of the objects on that floor and on higher and lower floors. Relative tilt error scores indicated a bias, in that targets that were higher than the test location were judged as consistently lower than their actual positions and targets that were lower than the test location were judged as consistently higher than their actual positions. Absolute tilt errors revealed an asymmetry, with more accurate and less variable tilt errors for judgments directed to lower floors than for judgments directed to higher floors. Experiment 3 ruled out an account of the findings that does not relate them to spatial memory. The results suggest that the superiority of downward over upward spatial judgments, previously reported in two-dimensional visual-spatial tasks, extends to navigational spatial memory.

First-perspective alignment effects in a computer-simulated environment.

In Experiment 1, participants explored two desktop, virtual environments (VEs), each comprising three city streets connected at right angles; for each participant one VE was open and one was enclosed. Following the first VE exploration, orientation estimates to remembered test locations were most accurate when participants imagined themselves aligned, rather than 90 degrees misaligned or 180 degrees or contra-aligned, with the first part of the route. In the second VE, the effect was attenuated and the data pattern conformed to that anticipated from an orientation-free memory. Experiment 2 followed the procedure of Experiment 1, but omitted the alignment tests after the first VE; following the second VE exploration, orientation estimates presented a similar pattern to those in first test of Experiment 1. These data are discussed in terms of cognitive load.

Effects of early mobility on shortcut performance in a simulated maze.

This experiment compared the shortcut choices of able-bodied teenagers with those of physically disabled teenagers who had varying histories of mobility impairment. In a computer-simulated kite-shaped maze, participants were allowed to explore three arms that connected four rooms. Subsequently they were offered a choice between paths connecting two rooms, one of which was a novel shortcut. Disabled teenagers chose correctly on fewer occasions than their able-bodied counterparts. Despite equivalent current levels of mobility, disabled participants whose mobility was more limited early in development were poorer at the task than those whose mobility had deteriorated with age. The results suggest that early independent exploration is important in the development of spatial knowledge, and suggest that the detrimental effects of limited early exploratory experience may persist into the teenage years.