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Cognitive map theory assumes that novel environmental information is automatically incorporated into existing cognitive maps as a function of exploration. Reports of blocking in place learning cast doubt on this claim. In these studies, subjects were first trained to find a place, using a set of landmarks (Set A). Then novel landmarks (Set B) were added for additional trials. Subsequent removal of the Set A landmarks showed that the novel landmarks alone were insufficient for successful navigation. We investigated whether instructing human subjects to explore the environment can moderate blocking. First, we demonstrated that blocking is absent in a computer implementation of the Morris water maze (MWM) in which subjects are instructed to explore. We then studied why others found blocking in a different MWM implementation, in which the task instructions did not suggest exploration. In experiments that faithfully replicated this MWM variant, we found that subjects did not acquire cognitive maps and that blocking was attenuated when instructions were provided that encouraged exploration. Together, these findings indicate that blocking in human place learning may reflect a performance deficit, not a learning deficit, and that instructions can moderate blocking. Our results thus support the automatic update assumption of cognitive map theory.

This research project aims at revealing the variety of critical spatial factors in an individual's mental map that influence daily activity travel behavior. A qualitative travel survey and in-depth interviews are used to identify spatial factors that appear in respondents' travel mode decisions when discussing their daily activity space. Recorded interviews are processed through ATLAS.ti. First, representative If--Then (--Else) heuristics used by respondents are identified and framed within the daily activity travel decision process and classified in a script network view. In addition, the spatial elements occurring are indicated. To conclude, this article suggests a new 'script' approach to grasp the behavioral mechanisms present in daily activity travel decisions and argues that further research along this line would contribute to the understanding of the impact of travel demand measures and its assessment in activity-based travel demand models by means of an agent-based computational process model. Keywords: activity-based modeling; spatial cognition; mental map; choice heuristics

Based on mental model theory, we expect individuals to construct a mental representation of the system they interact with which tends to be a strong reduction of reality and is tailored to the specific situation and task at hand. Such reductions may be particularly significant in complex decision situations involved in local spatial choice behavior. In this article, we develop a method to model and measure mental representations of decision problems involving individual spatio-temporal choice behavior in different situations. The so-called CNET method consists of an interview protocol to elicit the structures at the individual level as a causal network. We test the proposed method in a case study involving 180 respondents and an experimental shopping-trip planning task. The results indicate that the method is an adequate way of eliciting mental representations. We show how the networks revealed can be used to model and simulate reasoning and decision-making processes. Keywords: spatial choice behavior; mental models; cognitive mapping; Bayesian belief and decision networks; interview protocol

How the memory systems centered on the hippocampus and dorsal striatum interact to support behavior remains controversial. We used functional MRI while people learned the locations of objects by collecting and replacing them over multiple trials within a virtual environment comprising a landmark, a circular boundary, and distant cues for orientation. The relative location of landmark and boundary was occasionally changed, with specific objects paired with one or other cue, allowing dissociation of learning and performance relative to either cue. Right posterior hippocampal activation reflected learning and remembering of boundaryrelated locations, whereas right dorsal striatal activation reflected learning and remembering of landmark-related locations. Within the right hippocampus, anterior processing of environmental change (spatial novelty) was dissociated from posterior processing of location. Behavioral studies show that landmark-related learning obeys associative reinforcement, whereas boundary-related learning is incidental [Doeller CF, Burgess N (2008) Proc Natl Acad Sci USA 105:5909-5914]. The distinct incidental hippocampal processing of boundaries is suggestive of a 'geometric module' or 'cognitive map' and may explain the hippocampal support of incidental/observational learning in 'declarative' or 'episodic' memory versus the striatal support of trial-and-error learning in 'procedural' memory. Finally, the hippocampal and striatal systems appear to combine 'bottom-up,' simply influencing behavior proportional to their activations, without direct interaction, with 'top-down' ventromedial prefrontal involvement when both are similarly active. cognitive map | functional MRI | incidental | learning | procedural

This study examined how the geographic distribution of group members affected dominance perceptions in a field experiment involving 65 computer-mediated groups communicating over a 2-week period. Dominance perceptions were more extreme when group members did not share a geographic location (distributed groups) than when they did (collocated groups). Collocated groups showed greater convergence between self and partner dominance perceptions than distributed groups, suggesting more symmetrical perceptions. More symmetrical groups exhibited more attraction and cohesion than less symmetrical groups. These results lend some support to recent models of computer-mediated communication that take into consideration the social psychological processes involved in distributed work and run counter to studies suggesting status equalization in mediated group collaboration. Keywords: computer-mediated communication; dominance; virtual groups; distributed work; impression formation; social information processing; hyperpersonal model; symmetry

This article compares self-reported and objectively measured physical features in a large-scale environment. Environmental perception has been studied through object perception research but little is known about perception in full-scale environments. Also, few studies examine differences between self-reported and objective environments including the potential effects of distance and content. In this study, a questionnaire, satellite imagery, and geographic information system data were used. Results indicate that self-reported environments are different from objective environments. In addition, self-reported responses separate natural and built environments into two different dimensions. Water combines self-reported and objective measurements into a single dimension. Further analysis revealed that content (natural vs. built) and distance (300 ft vs. 1,500 ft) are important factors influencing the relationships between self-reported and objective environmental measurements. By better understanding relationships between self-reported and objective environments, landscape planners and designers can choose the most appropriate data type for analyzing specific planning and design decisions. Keywords: environmental perception; geographic information system; landscape content

Five experiments performed in a desktop virtual-reality setting investigated the influence of environmental features--that is, noticeable landmarks along the route--on distance estimation. Landmarks were of two types: Either they simply 'filled' the route or they 'filled' and also segmented it, thereby inducing a hierarchical structuring of the route. Previous research had left the question open of whether a filling or a segmenting feature leads to an overestimation of a distance along the route. Our experiments showed different results dependent on the kind of space: If an environment was learned from a route perspective, filling and segmenting environmental features led to overestimations of distances, while the segmenting of a route induced by a grouping of similar features did not. If the environment was learned from a map that afforded a survey perspective, route structuring induced through a segmenting feature or by phenomenal grouping led to an overestimation of distances, whereas features that merely filled the route did not.

The primary purpose of the experiments presented in this report was to study systematically the geographic site-name, associative memory of male and female college students (predominantly White and middle class) for locations that varied in distance: local, national, and international sites. In the first experiment, participants were to match listed names of campus buildings and local cities with their marked locations on maps. In the second experiment, under a site-name memory, a site-name/map-aid memory, and a map-aid/name-aid memory (site-name associative memory) condition, participants were to recall or match as many of the 50 US states and the 25 largest US cities as they could. In the third experiment, the participants were to match a listed grouping of the world's largest bodies of water and continents, a set of countries, and the world's largest cities, with their marked locations on maps. In the first experiment, men matched significantly more local cities than did women; in the second experiment, men recalled significantly more of the cities under the site-name/map-aid and the map-aid/name-aid memory conditions than did women; and in the third experiment, men matched significantly more sites on all three maps than did women. The absence of gender differences for campus buildings and states may have been a product of the participants having had extensive opportunities to learn these sites. That men displayed greater knowledge of cities and international sites suggests that they have a greater interest in geography than do women. Because of the limitations of the methodology used, the gender differences favoring men could not be interpreted as primarily a product of nature or of nurture, and thus it was concluded that they were a joint product of nature and nurture. KEY WORDS: spatial memory; gender differences; geography.

A digital divide of in the Internet use from a geographical perspective is examined. The activities performed online were analyzed in Korea. It was observed that netizens living in other parts out of Seoul (the capital of Korea) had relatively lower rates of engagement on the Internet.

Previous studies have shown that disoriented children use the geometric features of the environment to reorient, but the results have not consistently demonstrated whether children can combine such information with landmark information. Results indicating that they cannot suggest the existence of a geometric module for reorientation. However, results indicating that children can use geometric information in combination with landmark information challenge the modularity interpretation. An uncontrolled variable in the studies yielding conflicting results has been the size of the experimental space. In the present studies, which tested young children in spaces of two different sizes, the size of the space affected their ability to use available landmark information. In the small space, the children did not use the landmark to reorient, but in the large space they did. The ability of children to use landmarks in combination with geometric information raises important questions about the existence of an encapsulated geometric module.

Blind and blindfolded sighted observers were presented with auditory stimuli specifying target locations. The stimulus was either sound from a loudspeaker or spatial language (e.g., '2 o'clock, 16 ft'). On each trial, an observer attempted to walk to the target location along a direct or indirect path. The ability to mentally keep track of the target location without concurrent perceptual information about it (spatial updating) was assessed in terms of the separation between the stopping points for the 2 paths. Updating performance was very nearly the same for the 2 modalities, indicating that once an internal representation of a location has been determined, subsequent updating performance is nearly independent of the modality used to specify the representation.

The purpose of this study was to explore wayfinding behavior in an unfamiliar environment. The participants were 24 university freshmen. The main task was returning to the starting point after an 8-minute walk within complex buildings. The participants were encouraged to use the shortest path possible. A photo memory task, a route memory task, a pointing task and a sketch map of the route were also completed. Wayfinding performance was found to correlate with performances in the sketch map task and the pointing task, and with route scene memory. However, some participants who either drew incomplete sketch maps or had an inaccurate homing vector could also find their way with a minimum of errors. Their verbal explanations of their choices revealed that using route scenes, schema-like knowledge, environmental constraints, and information-seeking heuristics enabled them to find their way in the artificial environment.

This paper argues cognitive mapping is a learning process that can be simulated by a self-organizing neural network. The learning of city locations was considered in two studies. One study focused on the learning of city locations on four continents. Results indicated the neural network aligned the cities producing systematic errors similar to those in human cognitive maps. A second study had a neural network learn a biased sample of city locations in the United States. Results indicated a non-linear relationship between cognitive and physical distances. Self-organized cognitive maps naturally produce this non-linear relationship when information from more than one scale is mapped into one space. Key Words: learning, cognitive maps, neural networks, self-organized.

Many researchers believe that when people read spatial descriptions, they construct mental models of the configurations described. Payne (1993) proposed that reading a spatial description produces a memory of the operations used to construct a mental model, an episodic construction trace. The episodic construction trace hypothesis predicts that memory for a spatial description will be influenced by the degree of overlap between the construction processes required by the original description and the construction processes prompted by an item in a recognition test. The two experiments reported here show that readers of spatial descriptions are more likely to accept sentences in a recognition test that are consistent with the operations used to construct a mental model than to accept sentences that are inconsistent. Consistency with the episodic construction trace leads to both correct recognition of verbatim sentences from the original description and false recognition of sentences that were not present in the original descriptions.

Two experiments on insect navigation indicate that insects do not possess a cognitive map to move along new routes. The first experiment revealed that desert ants navigate by associating walking vectors and compass information or landmark memories. The second experiment shows that honeybees can integrate vector information from two routes to navigate a new route without using a cognitive map. These findings suggest that the cognitive-map concept is no longer applicable for understanding the spatial behavior of animals.

Studies reveal that using a computer-based, networked knowledge mapping system to assess teamwork processes is possible. Research is based on 23 groups consisting of 69 participants for a pre-test and 14 groups consisting of 42 participants for the post test, all drawn from six middle and high school classes located on American army bases in Germany; other topics include team processes, such as adaptability, coordination, decision making and leadership and issue raised by the study, what is a team and the effectiveness of the systems interface are also discussed.

Studies reveal that knowledge map scores significantly increase from fall to spring for students who create maps individually while searching web space containing both relevant and irrelevant information about environmental science, while there was no change on group maps. Results are based on two administrations of the National Center for Research on Evaluation, Standards, and Student Testing (CRESST) on 149 middle and high school students some constructing group maps and some constructing individual maps.

In each of 3 experiments, rats were preexposed to the 4 distinct landmarks surrounding a circular pool before being trained to find a submerged platform located in a fixed position in the pool. When preexposure was to pairs of adjacent landmarks, it consistently retarded subsequent learning (a latent inhibition effect). When preexposure was to 1 landmark at a time, then, provided the 4 landmarks all contained a salient feature in common, preexposure facilitated subsequent learning (a perceptual learning effect). The results provide little support for the notion of a cognitive map and are quite consistent with an associative analysis.

Studies on people's manner of storing and processing geographic information fall under the realm of cognitive mapping. A researcher is able to measure geographic elements such as distance and direction through experiments with controlled parameters. However, interpretation of data garnered from these studies are affected by locational cueing, that is, individuals' degree of prior familiarity with a location, as well as spatial cueing. To counter the effects of these cues, the experimental settings need to incorporate a strong construct and a convergent validity.

Byline: Mario Borroi (1), Mario Minoja (2), Alessandro Sinatra (3) Abstract: This paper discusses the relationship between the subjective organisation and the perceived competitive structure of an industry based on an empirical study of the Carpi textile-clothing district, which partially replicates a previous study of the Scottish knitwear industry conducted by other authors (Porac et al., 1995). The initial hypothesis to be tested is that an industry may be broken down into a number of subsets of firms within which competition is perceived as being fiercer as compared with firms in different subsets. These subsets, or groups, correspond to the groups or types of firms into which decision-makers -- managers and entrepreneurial business owners alike -- perceive the industry as being divided. The results of the study are then compared to the empirical evidence from the research conducted by other authors. This comparison provides some interesting elements for investigating the relationships between industry complexity, cognitive maps and strategies implemented by the firms belonging to it. After suggesting a definition of complexity of an industry as the number of strategies implemented in it by competitors, we discuss the hypothesis that key-actors in the firms develop a mental picture of their environment that tends to become less comprehensive and accurate as the degree of complexity of the environment itself increases. Author Affiliation: (1) Department of Computer and Management Science, University of Trento, Italy (2) Department of Business Policy, Bocconi University, Milan, Italy (3) Libero Istituto Universitario Carlo Cattaneo, Castellanza (VA), Italy Article History: Registration Date: 14/10/2004

Cognitive behaviorist E. C. Tolman (1932) proposed many years ago that rats and men navigate with the aid of cognitive maps, but his theory was incomplete. Critic E. R. Guthrie (1935) pointed out that Tolman's maps lack a rule for action, a route finder. We show that a dynamic model for stimulus generalization based on an elementary diffusion process can reproduce the qualitative properties of spatial orientation in animals: area-restricted search in the open field, finding shortcuts, barrier learning (the Umweg problem), spatial 'insight' in mazes, and radial maze behavior. The model provides a behavioristic reader for Tolman's cognitive map.

INTRODUCTION Spatial Memory and Cognitive Maps All organisms capable of locomotion have to deal with space and spatial relations within their environment. Simple tasks like efficient grazing and foraging, path [...], Spatial behavior in humans and animals includes a wide variety of behavioral competences and makes use of a large number of sensory cues. Here we studied the ability of human subjects to search locations, to find shortcuts and novel paths, to estimate distances between remembered places, and to draw sketch maps of the explored environment; these competences are related to goal-independent memory of space, or cognitive maps. Information on spatial relations was restricted to two types: a visual motion sequence generated by simulated movements in a virtual maze and the subject's own movement decisions defining the path through the maze. Visual information was local (i.e., no global landmarks or compass information was provided). Other position and movement information (vestibular or proprioceptive) was excluded. The amount of visual information provided was varied over four experimental conditions. The results indicate that human subjects are able to learn a virtual maze from sequences of local views and movements. The information acquired is local, consisting of recognized positions and movement decisions associated to them. Although simple associations of this type can be shown to be present in some subjects, more complete configurational knowledge is acquired as well. The results are discussed in a view-based framework of navigation and the representation of spatial knowledge by means of a view graph.

Two versions of a fictitious recreational park were developed. One described the location and order of 25 park landmarks as might be encountered by a driver (route version). The other (survey version) presented the same 25 landmarks using spatial or geographic referents. Both versions were 25 sentences in length. Subjects read either the route or survey version first, one sentence at a time. After reading the text, subjects were given 1 min. access to a map of the park. The route subjects were given a label map, which showed the location of park landmarks by name. The survey readers were given an icon map, which designated the same landmarks using pictures. After viewing the map, both groups were given a set of 20 inferential questions regarding the landmarks. Subjects then read the same text version again; however, half the subjects for each text version viewed the same map, while the other half received the alternate map form. All groups then answered the same set of inferential questions. A control group received no feedback on either reading. Analysis showed that, compared to the control group, the subjects with feedback showed greater gains in scores across trials. Survey text readers showed greater gains than route version readers. For both versions, readers given access to the alternate map showed greater gains than those who viewed the same map twice. Moreover, the survey readers benefited more from the map change than the route readers. The data support prior research which suggests that the survey text base appears more flexible in terms of making greater use of available feedback, even if different from the original.

This paper advances the spatial-choice modelling literature by further examining the way in which spatial knowledge is gained. The specific research purpose of this paper is to see how a major boundary (the U.S.A.Canada border) will affect the generation of a spatial-knowledge surface. It is accepted that an important impact on the way an individual makes a spatial choice, such as a decision to migrate, is the amount and quality of the information he / she possesses about different locations. A positive influence on such a knowledge surface is the population size of the location. Negative influences include the separating distance between individual and location, and the degree of clustering the location faces in respect to other places around it. This paper investigates the way in which these influences also hold if a major boundary lies between a subject and the investigated research space. The paper uses a multivariate model calibrated on lists of recalled United States city names generated at 9 different Canadian test sites. These are then compared to similar model results from 22 U.S. test sites. The Canadian test results are more consistent than those for the United States. Also, for Canadian subjects, there is no distance decay in the probability of recalling a location unless the Canadian test site is located proximate to a major American border city. A strong relationship exists between the population size of the recalled location and its probability of being recalled. There is also further evidence to support a hierarchical method of knowledge processing, albeit in a weaker form than found in the U.S. test sites. Key words: competing destinations, spatial choice, spatial knowledge

Decrements in spatial competence appear to be a normal aging characteristic and can occur in the absence of cognitive or sensory impairment (Georgemiller & Hassan, 1986). It has been suggested [...], Adults, ranging in age from 20 to 78 years, were required to give directions to a hypothetical stranger while looking at a map. The direction giving was scored according to the strategies employed by the direction giver (e.g., landmarks, relational turns, road names, and cardinality). The 'map present' direction-giving paradigm was employed to reduce the influence of memory. The results suggest that the aging decline in spatial abilities does not influence direction-giving strategies when memory demands are minimal. Older adults are as proficient as young adults when employing direction-giving strategies. Middle-age females employed a significantly higher frequency of strategies relative to young males, young females, middle age males, and older females. When accuracy was examined, gender-related differences favoring males were obtained for the relational strategy.

Research conducted at Fogg Dam in Australia's Northern Territory, an artificially created wetland populated by wildlife, reveals tourists' understanding of 'ecotourism.' Many tourists regarded the Fogg Dam as ecotourism. The survey suggests that a pristine area is not required by the ecotourist if the area is attractive and provides opportunity for learning or wildlife viewing.

Study of the Maoist Naxalite movement in India illustrates the potential contribution of spatial analysis to social movement studies. Social movement theory focuses on social processes in time, and on the cultural and structural backgrounds to social movements, but neglects the contributions which geographers can make through analysis of the spatial context. Spatiality, which includes concepts of location, locale and sense of place, offers information on issues including the wider spatial contexts of social movements and potential aids or hindrances to collective action.

The probability matrix decomposition (PMD) method is presented as a perceptual mapping technique for evaluating two-way two-mode frequency data. The method is different from latent class analysis by the binomial model and correspondence analysis in that it tests several decision rules which each comprises a divergent model of the psychological process. The application of PMD to judgments aggregated across respondents revealed the method's suitability in representing data and effectiveness in predicting consumer preference for sandwich fillings.

Old rats have deficient spatial memory which may mean that the quality and stability of their hippocampal cognitive maps is altered. The hippocampal spatial code was observed to be multistable in recordings from large groups of neurons. In old rates place field maps often showed complete rearrangements between episodes in a familiar environment. The spatial memory performance of old rates remained markedly bimodal. This offers an insight into the dynamics of neural coding and may explain why elderly humans undergo frequent failure of place recognition.

Navigating through an environment and viewing a map of that environment can result in different types of cognitive representation. Maps are typically encoded in the same orientation that they are viewed, while navigation results in an orientation-free representation. The present study concerns the orientation specificity of spatial knowledge following navigation in a computer-simulated space. Subjects either explored a simulated 3-D environment by navigating through it, or were presented with a map-like single orientation plan view of the same environment. When asked to indicate the direction of test objects that were not directly visible from within the simulation, response latencies suggested that the navigation group had an orientation-free representation while the map group had an orientation-specific representation. We conclude that navigation in computer-simulated space and real space lead to similar kinds of spatial knowledge.

The recurrent collaterals' synaptic efficacies in the CA3 area of the hippocampus generate a cognitive graph which is formed using long-term potentiation and is stored in the synaptic efficacies. The graph is used for spatial tasks and its connections contain information about the distance between the place fields of the place cells. Rats form the cognitive graph in the absence of motivation and later use it when a goal is provided. The information stored in the graph is probably read out by destination cells which are not present in the hippocampus.

CA3 pyramidal cells of the hippocampus form a cognitive graph which depends on long-term potentiation, place cells, and connections between the cells. The distance between the firing fields of the place cells is stored as synaptic resistance changes induced by long-term potentiation. The cognitive map is used to find the shortest path, shortcuts and detours in a two-dimensional space. The shortest path is obtained by minimizing the sum of the synaptic resistance in space. Neural processes are probably parallel graph searching algorithms that perform the mapping activity.

218 college students (96 men and 122 women, including nearly equal numbers of right-handers and left-handers) were administered a modified version of the 'Gallup Geography Test.' Men outperformed women, and left-handed women outperformed right-handed women. We suggest that these results cannot be easily explained by any credible sociocultural model but are consistent with a neuropsychological model of sex and handedness differences in spatial ability advanced by Harshman, Hampson, and Berenbaum in 1983.

The purpose of this study was to investigate the effect of varying the elevation of the computer graphics eyepoint and the geometric field of view on judgements of spatial information using a stereoscopic perspective display. Twelve subjects judged the elevation and azimuth angle separating two computer-generated objects viewed using an eyepoint elevation that ranged between - 15[degrees] and 45[degrees] and a geometric field of view that ranged between 40[degrees] and 80[degrees]. The results of the study indicated that judgements of elevation were affected by the compression of the vertical axis resulting from the raised eyepoint elevation. Furthermore, azimuth judgements were influenced by both the eyepoint elevation and the geometric field of view. Implications of the results for the design of displays and for spatial performance using stereoscopic displays are discussed. Keywords: spatial displays. stereoscopic displays, eyepoint elevation

The aim of the present work was to test some of the criteria for automaticity of spatial-location coding claimed by Hasher and Zacks, particularly individual differences (as intelligence invariance) and effortful encoding strategies. Two groups of subjects, 15 with mental retardation (Down Syndrome, mean chronological age, 20.9 yr.; mean mental age, 11.6 yr.) and 15 normal children (mean age, 11.5 yr.), were administered four kinds of stimuli (pictures, concrete words, nonsense pictures, and abstract words) at one location on a card. Subsequently, subjects were presented the items on the card's centre and were required to place the items in their original locations. Analysis indicated that those with Down Syndrome scored lower than normal children on the four tasks and that stimuli were better or worse remembered according to their characteristics, e.g., their imaginability. Results do not support some of the conditions claimed to be necessary criteria for automaticity in the recall of spatial locations as stated by Hasher and Zacks.

Pigeons trained to peck at a spot on a computer screen showing a grassy field and several landmarks responded jointly to global cues and the landmark closest to the spot. Some pigeons depended to an extent on two landmarks, if both were close to the spot, and color appeared to be much more important than shape in landmark identification. Overall screen location affected control but the configuration of landmarks did not. The experiment generalized several earlier findings using simpler computer figures.

Subjects in three experiments read texts describing the locations of landmarks in a fictitious town. Later they drew sketch maps and verified sentences describing the relative locations of the landmarks. We predicted that subjects would develop mental models of the town that were organized around important landmarks ('anchors'), as are cognitive maps constructed through real-world navigation. More specifically, we expected that landmarks used in the text as reference points for describing the locations of some other landmarks would emerge as anchors in the subjects' cognitive maps and would consequently be recalled more accurately. Results showed that subjects represented such reference-point landmarks more accurately than they did the locations of other landmarks. This effect was independent of: (1) the perspective from which the text was written (route or survey); (2) whether or not a map was present at learning; (3) the order of information in the text (linear or anchors-first), and (4) the amount of information available to the subjects while drawing sketch maps (the full text, the landmark names only, or no information).

Two studies examined spatial organization reflected in searches for objects and descriptions of locations. Six-year-olds and adults retrieved objects hidden on the floors of a house or directed another person about how to retrieve them. Of particular interest was whether children's searches and directions reflected clustering of locations by floors. Six-year-olds' searches were more organized than their directions, but a follow-up study demonstrated that they could produce organized directions if prompted. Analyses of the content and structure of spatial information in directions indicated that children and adults communicated the information in an order of decreasing size of spatial unit. Results are discussed in terms of factors underlying spatially organized searching and direction-giving.

The research reported here in the domain of cognitive mapping stems from a gestalt-oriented framework. The key words underlying this approach are orientation, rotation, and analog. Orientation and cognitive mapping [...], Tversky (1981) has argued that when a map has a natural orientation that does not correspond to that of its frame of reference, conditions are ideal for invoking the heuristic of rotation in its representation as a cognitive map. In the two studies reported here, such a situation was exploited with respect to judgment of orientation to cities within Israel. In both Experiments 1 and 2, which employed a recall-and-production method, a 15 |degrees~ counterclockwise rotation was predicted and found in orientation judgments.

Four experiments investigated the use of cognitive strategies for encoding spatial location in visual figures. Subjects reproduced the position of a dot in a square figure that had distance markers placed along two sides. Subjects' responses were biased toward imaginary points of intersection formed by the distance markers when subjects responded from memory (Experiment 1) or while viewing the figures (Experiment 2). Dots located at an intersection point were reproduced more accurately than those located off an intersection. These findings demonstrate that empty regions of a figure can serve as subjective landmarks for spatial localization. In Experiment 3, dot relocation was found to be similarly distorted toward physical cross marks placed at the intersections of distance markers, supporting the landmark hypothesis. The attraction of dots to intersection points depends on the viewer employing a strategy of mentally projecting from distance markers to form imaginary intersections, which makes intersection points salient landmarks for coding location of nearby stimulus dots. In Experiment 4, attraction toward intersection points was observed only when subjects employed the projection strategy and not when instructed to use a different encoding strategy.

An algorithm for the perception of edge information by a vision machine is presented in this paper. In this approach, the sensored visual data are transformed by the process of cognition into generalized manifestations called percepts and concepts. Machine cognition is hypothesized as the transformation of sensory information between the information domain and comprehension domain. Percepts are the mental impressions of the sensory data which arise within the information domain. On the other hand, concepts are meanings which are attached to these percepts in the comprehension domain. The mechanisms for transforming raw data into percepts and then attaching conceptual meanings to them may be described by cognitive mapping functions. In this paper, a fuzzy set theoretic approach is used to emulate the cognitive mapping processes that occur within the information domain. More specifically, this algorithm employs fuzzy mapping functions to transform sensory gray-level images into various properties associated with a perceived edge. This new notion interprets an edge as a field with distributed membership values that may be observed at various levels of perception.

Subjects viewed projected slides of a downtown city area and attempted to find on a map the location at which they would be standing to see each view. Plan and oblique maps were used. As expected, performance using the plan map was significantly better when the map was used in alignment with the view than when it was misaligned. This issue is more complex with the oblique map, because S often has to choose between using the map in alignment with the view and using the map in its upright orientation. Performance was significantly better when the map was used in map-view alignment. However, Ss preferred to use the map in an upright-but-misaligned orientation rather than a non-upright-but-aligned orientation, despite the fact that their performance was much worse in the former case.