Malleability in the development of spatial reorientation

Distinct neural mechanisms for heading retrieval and context recognition in the hippocampus during spatial reorientation

Reorientation, the process of regaining one's bearings after becoming lost, requires identification of a spatial context (context recognition) and recovery of facing direction within that context (heading retrieval). We previously showed that these processes rely on the use of features and geometry, respectively. Here, we examine reorientation behavior in a task that creates contextual ambiguity over a long timescale to demonstrate that male mice learn to combine both featural and geometric cues to recover heading. At the neural level, most CA1 neurons persistently align to geometry, and this alignment predicts heading behavior. However, a small subset of cells remaps coherently in a context-sensitive manner, which serves to predict context. Efficient heading retrieval and context recognition correlate with rate changes reflecting integration of featural and geometric information in the active ensemble. These data illustrate how context recognition and heading retrieval are coded in CA1 and how these processes change with experience.

What have we learned from research on the "geometric module"?

This article is an overview of the research and controversy initiated by Cheng's (Cognition, 23(2), 149-178, 1986) article hypothesizing a purely geometric module in spatial representation. Hundreds of experiments later, we know much more about spatial behavior across a very wide array of species, ages, and kinds of conditions, but there is still no consensus model of the phenomena. I argue for an adaptive combination approach that entails several principles: (1) a focus on ecological niches and the spatial information they offer; (2) an approach to development that is experience-expectant: (3) continued plasticity as environmental conditions change; (4) language as one of many cognitive tools that can support spatial behavior.

Environment geometry alters subiculum boundary vector cell receptive fields in adulthood and early development

Boundaries to movement form a specific class of landmark information used for navigation: Boundary Vector Cells (BVCs) are neurons which encode an animal's location as a vector displacement from boundaries. Here we characterise the prevalence and spatial tuning of subiculum BVCs in adult and developing male rats, and investigate the relationship between BVC spatial firing and boundary geometry. BVC directional tunings align with environment walls in squares, but are uniformly distributed in circles, demonstrating that environmental geometry alters BVC receptive fields. Inserted barriers uncover both excitatory and inhibitory components to BVC receptive fields, demonstrating that inhibitory inputs contribute to BVC field formation. During post-natal development, subiculum BVCs mature slowly, contrasting with the earlier maturation of boundary-responsive cells in upstream Entorhinal Cortex. However, Subiculum and Entorhinal BVC receptive fields are altered by boundary geometry as early as tested, suggesting this is an inherent feature of the hippocampal representation of space.

Reorientation by features and geometry: Effects of healthy and degenerative age-related cognitive decline

The ability to orient is critical for mobile species. Two visual cues, geometry (e.g., distance and direction) and features (e.g., colour and texture) are often used when establishing one's orientation. Previous research has shown the use of these cues, in particular, geometry, may decline with healthy aging. Few studies have examined whether degenerative aging processes show similar time points for the decline of geometry use. The present study examined this issue by training adult and aged mice from two strains, a healthy wild-type and an Alzheimer's model, to search for a hidden platform in a rectangular water maze. The shape of the maze provided geometric information, and distinctive features were displayed on the walls. Following training, manipulations to the features were made to examine whether the mice were able to use the features and geometry, and whether they showed a preference between these two cue types. Results showed that although Alzheimer's transgenic mice were slower to learn the task, overall age rather than strain, was associated with a degradation in use of geometry. However, the presence of seemingly uninformative features (due to their redundancy) facilitated the use of geometry. Additionally, when features and geometry provided conflicting information, only young wild-type mice showed a primary use of features. Our results suggest the failure to use geometry may be a generalized function of aging, and not a diagnostic feature of degeneration for mice. Whether this is also the case for other mammals, such as humans for which the mouse is an important medical model, remains to be examined.

Spatial reorientation with a geometric array of auditory cues

A visuocentric bias has dominated the literature on spatial navigation and reorientation. Studies on visually accessed environments indicate that, during reorientation, human and non-human animals encode the geometric shape of the environment, even if this information is unnecessary and insufficient for the task. In an attempt to extend our limited knowledge on the similarities and differences between visual and non-visual navigation, here we examined whether the same phenomenon would be observed during auditory-guided reorientation. Provided with a rectangular array of four distinct auditory landmarks, blindfolded, sighted participants had to learn the location of a target object situated on a panel of an octagonal arena. Subsequent test trials were administered to understand how the task was acquired. Crucially, in a condition in which the auditory cues were indistinguishable (same sound sample), participants could still identify the correct target location, suggesting that the rectangular array of auditory landmarks was encoded as a geometric configuration. This is the first evidence of incidental encoding of geometric information with auditory cues and, consistent with the theory of functional equivalence, it supports the generalisation of mechanisms of spatial learning across encoding modalities.

Navigation and the developing brain

As babies rapidly acquire motor skills that give them increasingly independent and wide-ranging access to the environment over the first two years of human life, they decrease their reliance on habit systems for spatial localization, switching to their emerging inertial navigation system and to allocentric frameworks. Initial place learning is evident towards the end of the period. From 3 to 10 years, children calibrate their ability to encode various sources of spatial information (inertial information, geometric cues, beacons, proximal landmarks and distal landmarks) and begin to combine cues, both within and across systems. Geometric cues are important, but do not constitute an innate and encapsulated module. In addition, from 3 to 10 years, children build the capacity to think about frames of reference different from their current one (i.e. to perform perspective taking). By around 12 years, we see adult-level performance and adult patterns of individual differences on cognitive mapping tasks requiring the integration of vista views of space into environmental space. These lines of development are continuous rather than stage-like. Spatial development builds on important beginnings in the neural systems of newborns, but changes in experience-expectant ways with motor development, action in the world and success–failure feedback. Human systems for integrating and manipulating spatial information also benefit from symbolic capacities and technological inventions.

Comparative spatial memory and cue use: The contributions of Marcia L. Spetch to the study of small-scale spatial cognition

Dr. Marcia Spetch is a Canadian experimental psychologist who specializes in the study of comparative cognition. Her research over the past four decades has covered many diverse topics, but focused primarily on the comparative study of small-scale spatial cognition, navigation, decision making, and risky choice. Over the course of her career Dr. Spetch has had a profound influence on the study of these topics, and for her work she was named a Fellow of the Association for Psychological Science in 2012, and a Fellow of the Royal Society of Canada in 2017. In this review, I provide a biographical sketch of Dr. Spetch's academic career, and revisit her contributions to the study of small-scale spatial cognition in two broad areas: the use of environmental geometric cues, and how animals cope with cue conflict. The goal of this review is to highlight the contributions of Dr. Spetch, her students, and her collaborators to the field of comparative cognition and the study of small-scale spatial cognition. As such, this review stands to serve as a tribute and testament to Dr. Spetch's scientific legacy.

Self-Organized Attractor Dynamics in the Developing Head Direction Circuit

Head direction (HD) cells are neurons found in an extended cortical and subcortical network that signal the orientation of an animal’s head relative to its environment [1, 2, 3]. They are a fundamental component of the wider circuit of spatially responsive hippocampal formation neurons that make up the neural cognitive map of space [4]. During post-natal development, HD cells are the first among spatially modulated neurons in the hippocampal circuit to exhibit mature firing properties [5, 6], but before eye opening, HD cell responses in rat pups have low directional information and are directionally unstable [7, 8]. Using Bayesian decoding of HD cell ensemble activity recorded in the anterodorsal thalamic nucleus (ADN), we characterize this instability and identify its source: under-signaling of angular head velocity, which incompletely shifts the directional signal in proportion to head turns. We find evidence that geometric cues (the corners of a square environment) can be used to mitigate this under-signaling and, thereby, stabilize the directional signal even before eye opening. Crucially, even when directional firing cannot be stabilized, ensembles of unstable HD cells show short-timescale (1–10 s) temporal and spatial couplings consistent with an adult-like HD network. The HD network is widely modeled as a continuous attractor whose output is one coherent activity peak, updated during movement by angular head velocity signals and anchored by landmark cues [9, 10, 11]. Our findings present strong evidence for this model, and they demonstrate that the required network circuitry is in place and functional early during development, independent of reference to landmark information.

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Non-visual cues can anchor head direction (HD) cells in pre-eye-opening rat pups

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Internal network dynamics are preserved even when the HD representation is unstable

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Angular velocity under-signaling drives instability, which is mitigated by corners

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Circuit architecture develops even before any landmarks can stabilize HD responses

First Direct Evidence of Cue Integration in Reorientation: A New Paradigm

There are several models of the use of geometric and feature cues in reorientation (Cheng, Huttenlocher, & Newcombe, ). The adaptive combination approach posits that people integrate cues with weights that depend on cue salience and learning, or, when discrepancies are large, they choose between cues based on these variables (Cheng, Shettleworth, Huttenlocher, & Rieser, ; Newcombe & Huttenlocher, ). In a new paradigm designed to evaluate integration and choice, disoriented participants attempted to return to a heading direction, in a trapezoidal enclosure in which feature and geometric cues both unambiguously specified a heading, but later the feature was moved. With discrepancies greater than 90 degrees, participants choose geometry. With smaller discrepancies, integration appeared in three of five situations; otherwise, participants used geometry alone. Variation depended on direction of feature movement and whether the nearest corner was acute or obtuse. The results have implications for contrasting adaptive combination and modularity theory, and for future research, offering a new paradigm for reorientation research, and for testing cue integration more broadly.

An adaptive cue combination model of human spatial reorientation

Previous research has proposed an adaptive cue combination view of the development of human spatial reorientation (Newcombe & Huttenlocher, 2006), whereby information from multiple sources is combined in a weighted fashion in localizing a target, as opposed to being modular and encapsulated (Hermer & Spelke, 1996). However, no prior work has formalized this proposal and tested it against existing empirical data. We propose a computational model of human spatial reorientation that is motivated by probabilistic approaches to optimal perceptual cue integration (e.g. Ernst & Banks, 2002) and to spatial location coding (Huttenlocher, Hedges, & Duncan, 1991). We show that this model accounts for data from a variety of human reorientation experiments, providing support for the adaptive combination view of reorientation.

Spatial Impairment and Memory in Genetic Disorders: Insights from Mouse Models

Research across the cognitive and brain sciences has begun to elucidate some of the processes that guide navigation and spatial memory. Boundary geometry and featural landmarks are two distinct classes of environmental cues that have dissociable neural correlates in spatial representation and follow different patterns of learning. Consequently, spatial navigation depends both on the type of cue available and on the type of learning provided. We investigated this interaction between spatial representation and memory by administering two different tasks (working memory, reference memory) using two different environmental cues (rectangular geometry, striped landmark) in mouse models of human genetic disorders: Prader-Willi syndrome (PWScrm+/p- mice, n = 12) and Beta-catenin mutation (Thr653Lys-substituted mice, n = 12). This exploratory study provides suggestive evidence that these models exhibit different abilities and impairments in navigating by boundary geometry and featural landmarks, depending on the type of memory task administered. We discuss these data in light of the specific deficits in cognitive and brain function in these human syndromes and their animal model counterparts.

Avian cognition: examples of sophisticated capabilities in space and song

Although birds have traditionally and colloquially been considered less cognitively complex than mammals, and especially primates, more recent research has consistently refuted these assumptions. We argue that the impressive abilities of birds to navigate and communicate require considerable information-processing capabilities. These capacities include collecting, organizing, and selecting from a wide variety of navigational cues to orient toward and find a goal location in the spatial domain, and utilizing open-ended categorization and possibly even abstract reasoning to discriminate species-specific acoustic features of songs and calls. Furthermore, these abilities may be present across many avian species, providing evidence for domain-general cognitive facilities. We provide examples of processes in spatial learning and communication in birds, and locate them within the general literature, as evidence that the term 'bird-brain' should not be considered a pejorative.

Geometric and featural systems, separable and combined: Evidence from reorientation in people with Williams syndrome

Spatial reorientation by humans and other animals engages geometric representations of surface layouts as well as featural landmarks; however, the two types of information are thought to be behaviorally and neurally separable. In this paper, we examine the use of these two types of information during reorientation among children and adults with Williams syndrome (WS), a genetic disorder accompanied by abnormalities in brain regions that support use of both geometry and landmarks. Previous studies of reorientation in adolescents and adults with WS have shown deficits in the ability to use geometry for reorientation, but intact ability to use features, suggesting that the two systems can be differentially impaired by genetic disorder. Using a slightly modified layout, we found that many WS participants could use geometry, and most could use features along with geometry. However, the developmental trajectories for the two systems were quite different from one other, and different from those found in typical development. Purely geometric responding was not correlated with age in WS, and search processes appeared similar to those in typically developing (TD) children. In contrast, use of features in combination with geometry was correlated with age in WS, and search processes were distinctly different from TD children. The results support the view that use of geometry and features stem from different underlying mechanisms, that the developmental trajectories and operation of each are altered in WS, and that combination of information from the two systems is atypical. Given brain abnormalities in regions supporting the two kinds of information, our findings suggest that the co-operation of the two systems is functionally altered in this genetic syndrome.

A new biomarker to examine the role of hippocampal function in the development of spatial reorientation in children: a review

Spatial navigation is an adaptive skill that involves determining the route to a particular goal or location, and then traveling that path. A major component of spatial navigation is spatial reorientation, or the ability to reestablish a sense of direction after being disoriented. The hippocampus is known to be critical for navigating, and has more recently been implicated in reorienting in adults, but relatively little is known about the development of the hippocampus in relation to these large-scale spatial abilities in children. It has been established that, compared to school-aged children, preschool children tend to perform poorly on certain spatial reorientation tasks, suggesting that their hippocampi may not be mature enough to process the demands of such a task. Currently, common techniques used to examine underlying brain activity, such as electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), are not suitable for examining hippocampal development in young children. In the present paper, we argue instead for the use of eyeblink conditioning (EBC), a relatively under-utilized, inexpensive, and safe method that is easy to implement in developing populations. In addition, EBC has a well defined neural circuitry, which includes the hippocampus, making it an ideal tool to indirectly measure hippocampal functioning in young children. In this review, we will evaluate the literature on EBC and its relation to hippocampal development, and discuss the possibility of using EBC as an objective measure of associative learning in relation to large-scale spatial skills. We support the use of EBC as a way to indirectly access hippocampal function in typical and atypical populations in order to characterize the neural substrates associated with the development of spatial reorientation abilities in early childhood. As such, EBC is a potential, simple biomarker for success in tasks that require the hippocampus, including spatial reorientation.

How Clark's nutcrackers (Nucifraga columbiana) weigh geometric cues depends on their previous experience

Following passive disorientation, Clark's nutcrackers (Nucifraga columbiana) learned to search for a hidden food reward located in one corner of a rectangular-shaped enclosure that contained either identical or distinct features in each corner. Identical features allowed for explicit learning of geometric cues, whereas distinct features allowed for both explicit learning of featural cues and incidental learning of geometric cues. Birds that only learned about geometry incidentally (group Distinct) weighed features greater than geometry when the two cues were placed in conflict. However, birds that received explicit training with geometry, in addition to feature training (groups Distinct-Identical and Identical-Distinct), weighed geometry heavier relative to features. Cue preference by the birds also depended on the order in which learning was experienced; if explicit training with geometry followed that of features (group Distinct-Identical), then both geometry and features were weighed equally, but if explicit training with geometry training preceded that of features (group Identical-Distinct), the birds weighed geometry greater than features. Results suggest both a heightened sensitivity to geometric cues by Clark's nutcrackers relative to other species of birds and an increased sensitivity to any spatial cue (either features or geometry) that has proven both stable and reliable.

25 years of research on the use of geometry in spatial reorientation: a current theoretical perspective

The purpose of this article is to review and evaluate the range of theories proposed to explain findings on the use of geometry in reorientation. We consider five key approaches and models associated with them and, in the course of reviewing each approach, five key issues. First, we take up modularity theory itself, as recently revised by Lee and Spelke (Cognitive Psychology, 61, 152-176, 2010a; Experimental Brain Research, 206, 179-188, 2010b). In this context, we discuss issues concerning the basic distinction between geometry and features. Second, we review the view-matching approach (Stürzl, Cheung, Cheng, & Zeil, Journal of Experimental Psychology: Animal Behavior Processes, 34, 1-14, 2008). In this context, we highlight the possibility of cross-species differences, as well as commonalities. Third, we review an associative theory (Miller & Shettleworth, Journal of Experimental Psychology: Animal Behavior Processes, 33, 191-212, 2007; Journal of Experimental Psychology: Animal Behavior Processes, 34, 419-422, 2008). In this context, we focus on phenomena of cue competition. Fourth, we take up adaptive combination theory (Newcombe & Huttenlocher, 2006). In this context, we focus on discussing development and the effects of experience. Fifth, we examine various neurally based approaches, including frameworks proposed by Doeller and Burgess (Proceedings of the National Academy of Sciences of the United States of America, 105, 5909-5914, 2008; Doeller, King, & Burgess, Proceedings of the National Academy of Sciences of the United States of America, 105, 5915-5920, 2008) and by Sheynikhovich, Chavarriaga, Strösslin, Arleo, and Gerstner (Psychological Review, 116, 540-566, 2009). In this context, we examine the issue of the neural substrates of spatial navigation. We conclude that none of these approaches can account for all of the known phenomena concerning the use of geometry in reorientation and clarify what the challenges are for each approach.

Sex differences in the weighting of metric and categorical information in spatial location memory

According to the Category Adjustment model, remembering a spatial location involves the Bayesian combination of fine-grained and categorical information about that location, with each cue weighted by its relative certainty. However, individuals may differ in terms of their certainty about each cue, resulting in estimates that rely more or less on metric or categorical representations. To date, though, very little research has examined individual differences in the relative weighting of these cues in spatial location memory. Here, we address this gap in the literature. Participants were asked to recall point locations in uniform geometric shapes and in photographs of complex, natural scenes. Error patterns were analyzed for evidence of a sex difference in the relative use of metric and categorical information. As predicted, women placed relatively more emphasis on categorical cues, while men relied more heavily on metric information. Location reproduction tasks showed a similar effect, implying that the sex difference arises early in spatial processing, possibly during encoding.

Size does not matter, but features do: Clark's nutcrackers (Nucifraga columbiana) weigh features more heavily than geometry in large and small enclosures

Two groups of Clark's nutcrackers (Nucifraga columbiana) were trained to locate a hidden goal which was consistently located at one corner of a fully enclosed rectangular environment with distinctive cues available at each corner. One group was trained in a small enclosure, whereas the second group was trained in a large enclosure. Once the birds were showing accurate search behavior, they were presented with non-reinforced tests in either the same sized environment as training or the novel sized environment, as well as in a square-shaped environment. The birds were able to accurately search at the two geometrically correct corners when the four distinctive features were removed showing that they had encoded geometry. Although accuracy was greater when tested in the same sized environment as during training, accuracy was above chance in both environments. Regardless of the size of training enclosure both groups showed primary control by features along with secondary control by geometry. Furthermore, when the features and geometric cues provided conflicting information as to the goal location, both groups weighed featural cues over geometry, and this was independent of whether the size of the testing environment was maintained or manipulated. These results show that for Clark's nutcrackers the size of the environment had little effect on the weighing of featural and geometric cues. Furthermore, although nutcrackers encoded both features and geometry, when spatial cues provided discrepant information as to the goal location, nutcrackers relied primarily on features. This article is part of a Special Issue entitled: CO3 2013.

Core systems of geometry in animal minds

Research on humans from birth to maturity converges with research on diverse animals to reveal foundational cognitive systems in human and animal minds. The present article focuses on two such systems of geometry. One system represents places in the navigable environment by recording the distance and direction of the navigator from surrounding, extended surfaces. The other system represents objects by detecting the shapes of small-scale forms. These two systems show common signatures across animals, suggesting that they evolved in distant ancestral species. As children master symbolic systems such as maps and language, they come productively to combine representations from the two core systems of geometry in uniquely human ways; these combinations may give rise to abstract geometric intuitions. Studies of the ontogenetic and phylogenetic sources of abstract geometry therefore are illuminating of both human and animal cognition. Research on animals brings simpler model systems and richer empirical methods to bear on the analysis of abstract concepts in human minds. In return, research on humans, relating core cognitive capacities to symbolic abilities, sheds light on the content of representations in animal minds.

A modular geometric mechanism for reorientation in children

Although disoriented young children reorient themselves in relation to the shape of the surrounding surface layout, cognitive accounts of this ability vary. The present paper tests three theories of reorientation: a snapshot theory based on visual image-matching computations, an adaptive combination theory proposing that diverse environmental cues to orientation are weighted according to their experienced reliability, and a modular theory centering on encapsulated computations of the shape of the extended surface layout. Seven experiments test these theories by manipulating four properties of objects placed within a cylindrical space: their size, motion, dimensionality, and distance from the space's borders. Their findings support the modular theory and suggest that disoriented search behavior centers on two processes: a reorientation process based on the geometry of the 3D surface layout, and a beacon-guidance process based on the local features of objects and surface markings.