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Spatial scaling, or an understanding of how distances in different-sized spaces relate to each other, is fundamental for many spatial tasks and relevant for success in numerous professions. Previous research has suggested that adults use mental transformation strategies to mentally scale spatial input, as indicated by linear increases in response times and accuracies with larger scaling magnitudes. However, prior research has not accounted for possible difficulties in encoding spatial information within smaller spaces. Thus, the present study used a discrimination task in which we systematically pitted absolute size of the spaces against scaling magnitude. Adults (N = 48) were presented with 2 pictures, side-by-side on a computer display, each of which contained a target. Adults were asked to decide whether the targets were in the same position or not, by pressing the respective computer key. In the constant-large condition, the constant space was kept large, whereas the size of the other space was variable and smaller. In the constant-small condition, the constant space was small, whereas the size of the other space was variable and larger. Irrespective of condition, adults' discrimination performance (d-primes) and response times were linear functions of scaling magnitude, supporting the notion that analog imagery strategies are used in spatial scaling. [ABSTRACT FROM AUTHOR]

Research on the existence of cognitive maps and on the cognitive processes that support effective navigation has often focused on functioning across individuals. However, there are pronounced individual differences in navigation proficiency, which need to be explained and which can illuminate our understanding of cognitive maps and effective navigation. Using a virtual environment involving 2 routes (Virtual Silcton, a desktop virtual environment; Weisberg, Schinazi, Newcombe, Shipley, & Epstein, 2014), we divided people into 3 groups based on their within-route and between-route pointing accuracy: integrators, non-integrators, and imprecise navigators. In Study 1, we found that imprecise navigators have lower spatial and verbal working memory, which may limit their ability to build accurate within-route representations. We also found that integrators maintain excellent memories of buildings as categorized by route membership, possibly supporting the idea of hierarchical representations of the environment. In Study 2, we assessed preferences regarding place and route learning using a virtual version of the rodent T-maze (Marchette, Bakker, & Shelton, 2011). Integrators found more goals overall, and although they did not have an overall preference for a place-based strategy, integrators who did choose a place-based strategy found more goals. The opposite was true for imprecise navigators. In Study 3, we added a monetary incentive for accuracy to evaluate whether increased motivation leads to fewer participants classified as imprecise, but found no significant change in the distribution of performance. These data have theoretical implications for the cognitive map hypothesis, and practical implications for improving navigational functioning. A one-size-fits-all approach may fit none. [ABSTRACT FROM AUTHOR]

Memories for spatial locations often show systematic errors toward the central value of the surrounding region. The Category Adjustment (CA) model suggests that this bias is due to a Bayesian combination of categorical and metric information, which offers an optimal solution under conditions of uncertainty (Huttenlocher, Hedges, & Duncan, 1991). A fundamental assumption of this model is that representations of locations are unbiased but uncertain; during cohibination, greater metric uncertainty results in relatively greater emphasis on categorical information, ultimately leading to increased bias (but also minimizing error across multiple estimates). Sampaio and Wang (2009) have demonstrated that metric information is not lost during this combination process, supporting the CA model's assumption that underlying spatial representations are undistorted. Here, we examine the 2nd half of the CA model's central assumption: that increasing metric uncertainty drives the combination process. Participants recognized point locations within visually complex images in a 4-choice task. Our results indicate that individuals recognized the correct location over other, biased alternatives, confirming that metric information is unbiased at the time of retrieval. In addition, we found that, when participants make errors, they are more likely to select locations that are biased toward the category prototype. In Experiment 2, we demonstrate that categorically biased locations are most likely to be chosen under conditions of uncertainty. Indeed, under these conditions, categorically biased locations were chosen more frequently than the correct location. These results suggest that systematic errors are the result of combination across multiple levels of spatial representations that are undistorted but somewhat uncertain. [ABSTRACT FROM AUTHOR]

Studies of spatial representation generally focus on flat environments and visual input. However, the world is not flat, and slopes are part of most natural environments. In a series of 4 experiments, we examined whether humans can use a slope as a source of allocentric, directional information for reorientation. A target was hidden in a corner of a square, featureless enclosure tilted at a 50 angle. Finding it required using the vestibular, kinesthetic, and visual cues associated with the slope gradient. In Experiment I, the overall sample performed above chance, showing that slope is sufficient for reorientation in a real environment. However, a sex difference emerged; men outperformed women by 1.4 SDs because they were more likely to use a slope-based strategy. In Experiment 2, attention was drawn to the slope, and participants were prompted to rely on it to solve the task; however, men still outperformed women, indicating a greater ability to use slope. In Experiment 3, we excluded the possibility that women's disadvantage was due to wearing heeled footwear. In Experiment 4, women required more time than men to identify the uphill direction of the slope gradient; this suggests that, in a bottom-up fashion, a perceptual or attentional difficulty underlies women's disadvantage in the ability to use slope and their decreased reliance on this cue. Overall, a bi-coordinate representation was used to find the goal: The target was encoded primarily with respect to the vertical axis and secondarily with respect to the orthogonal axis of the slope. [ABSTRACT FROM AUTHOR]

Recent studies have used spatial reorientation task paradigms to identify underlying cognitive mechanisms of navigation in children, adults, and a range of animal species. Despite broad interest in this task across disciplines, little is known about the brain bases of reorientation. We used functional magnetic resonance imaging to examine neural activity in adults during a virtual reality version of the reorientation task. Three environments that varied in the cues provided were studied: a rectangular room with 4 identical gray walls (Geometry), a square room with 3 gray walls and 1 red wall (Feature), and a rectangular room with 3 gray walls and 1 red wall (Feature + Geometry). Multiple areas within the medial temporal lobe (MTL) showed increased activation when a feature was present compared with when reorientation was based only on geometric cues. In contrast, reliance on geometric cues significantly activated a number of non-MTL structures, including the prefrontal cortex and inferior temporal gyrus. These results provide neural evidence for processing differences between the 2 types of cue as well as insight into developmental and comparative aspects of reorientation. [ABSTRACT FROM AUTHOR]

This research was an investigation of children's performance on a task that requires memory binding. In Experiments 1 and 2, 4-year-olds, 6-year-olds, and adults viewed complex pictures and were tested on memory for isolated parts in the pictures and on the part combinations (combination condition). The results suggested improvement in memory for the combinations between the ages of 4 and 6 years but not in memory for the isolated parts. In Experiments 2 and 3, the authors also examined the developmental relationship between performance in the combination condition and free recall of a naturalistic event, finding preliminary evidence that performance on a memory task that requires binding is positively related to performance in episodic memory. [ABSTRACT FROM AUTHOR]

Relying on shared tasks and stimuli to conduct research can enhance the replicability of findings and allow a community of researchers to collect large data sets across multiple experiments. This approach is particularly relevant for experiments in spatial navigation, which often require the development of unfamiliar large-scale virtual environments to test participants. One challenge with shared platforms is that undetected technical errors, rather than being restricted to individual studies, become pervasive across many studies. Here, we discuss the discovery of a software bug in a virtual environment platform used to investigate individual differences in spatial navigation: Virtual Silcton. The bug, which was difficult to detect for several reasons, resulted in storing the absolute value of a direction in a pointing task rather than the signed direction and rendered the original sign of the direction unrecoverable. To assess the impact of the bug on published findings, we collected a new data set for comparison. Results revealed that although the bug caused suppression in pointing errors and had different effects across people (less accurate navigators had more suppression), the effect of the bug on published data is small, partially explaining the difficulty in detecting the bug. We also used the new data set to develop a tool that allows researchers who have previously used Virtual Silcton to evaluate the impact of the bug on their findings. We summarize the ways that shared open materials, shared data, and collaboration can pave the way for better science to prevent errors in the future. [ABSTRACT FROM AUTHOR]

In the real word, we perceive our environment as a series of static and dynamic views, with viewpoint transitions providing a natural link from one static view to the next. The current research examined if experiencing such transitions is fundamental to learning the spatial layout of small-scale displays. In Experiment 1, participants viewed a tabletop array from 4 orientations in 1 of 3 conditions. The control condition presented the array sequentially, as a series of static views. In the remaining conditions, participants experienced the transition between viewpoints by rotating the array or moving around it. Both transitions improved spatial performance. Experiment 2 added a passive rotation condition to examine the effect of watching the transition without actively generating it. Spatial performance was equivalent across active and passive rotation conditions, with both outperforming static views. Together, these findings suggest that continuous visual flow is key to small-scale spatial learning. [ABSTRACT FROM AUTHOR]

Although the hippocampus is implicated in both spatial navigation and associative memory, very little is known about whether individual differences in the 2 domains covary. People who prefer to navigate using a hippocampal-dependent place strategy may show better performance on associative memory tasks than those who prefer a caudate-dependent response strategy (Bohbot, Gupta, Banner, & Dahmani, 2011), but not all studies suggest such an effect (Woollett & Maguire, 2009, 2012). Here we tested nonexpert young adults and found that preference for a place strategy positively correlated with spatial (object-location) associative memory performance but did not correlate with nonspatial (face-name) associative memory performance. Importantly, these correlations differed from each other, indicating that the relation between navigation strategy and associative memory is specific to the spatial domain. In addition, the 2 associative memory tasks significantly correlated, suggesting that object-location memory taps into processes relevant to both hippocampal-dependent navigation and nonspatial associative memory. Our findings also suggest that individual differences in spatial associative memory may account for some of the variance in navigation strategies. [ABSTRACT FROM AUTHOR]

There are marked individual differences in the formation of cognitive maps both in the real world and in virtual environments (VE; e.g., Blajenkova, Motes, & Kozhevnikov, 2005; Chai & Jacobs, 2010; Ishikawa & Montello, 2006; Wen, Ishikawa, & Sato, 2011). These differences, however, are poorly understood and can be difficult to assess except by self-report methods. VEs offer an opportunity to collect objective data in environments that can be controlled and standardized. In this study, we designed a VE consisting of buildings arrayed along 2 separated routes, allowing for differentiation of between-route and within-route representation. Performance on a pointing task and a model-building task correlated with self-reported navigation ability. However, for participants with lower levels of between-route pointing, the Santa Barbara Sense of Direction scale (Hegarty, Richardson, Montello, Lovelace, & Subbiah, 2002) did not predict individual differences in accuracy when pointing to buildings within the same route. Thus, we confirm the existence of individual differences in the ability to construct a cognitive map of an environment, identify both the strengths and the potential weaknesses of self-report measures, and isolate a dimension that may help to characterize individual differences more completely. The VE designed for diis study provides an objective behavioral measure of navigation ability that can be widely used as a research tool. [ABSTRACT FROM AUTHOR]

Memories for spatial locations often show systematic errors toward the central value of the surrounding region. This bias has been explained using a Bayesian model in which fine-grained and categorical information are combined (Huttenlocher, Hedges, & Duncan, 1991). However, experiments testing this model have largely used locations contained in simple geometric shapes. Use of this paradigm raises 2 issues. First, do results generalize to the complex natural world? Second, what types of information might be used to segment complex spaces into constituent categories? Experiment 1 addressed the 1st question by showing a bias toward prototypical values in memory for spatial locations in complex natural scenes. Experiment 2 addressed the 2nd question by manipulating the availability of basic visual cues (using color negatives) or of semantic information about the scene (using inverted images). Error patterns suggest that both perceptual and conceptual information are involved in segmentation. The possible neurological foundations of location memory of this kind are discussed. [ABSTRACT FROM AUTHOR]

The geometry formed by the walls of a room is known to be a potent cue in reorientation, yet little is known about the use of geometric information gleaned from other contexts. We used functional magnetic resonance imaging to examine neural activity in adults while reorienting in 3 different environments: the typical rectangular walled room, a rectangular configuration of pillars in an open field, and a rectangular floor in an open field. Behavioral response patterns for the 3 environments were similar, but pairwise contrasts of brain activation revealed differences at the neural level. We observed greater medial temporal lobe (MTL) involvement when reorienting with the pillars versus the walls and floor. In addition, the walled room selectively engaged areas of posterior parahippocampal cortex corresponding to the parahippocampal place area, when compared with the floor. Finally, a conjunction analysis of the 3 geometry conditions, compared with a control task, revealed activation in the primary auditory cortex that was common to all geometry conditions. These findings add to growing evidence that adults use verbal processes to encode environment geometry and that the reorientation tasks that young children find difficult are particularly hippocampus-dependent. [ABSTRACT FROM AUTHOR]