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Various lifestyle factors, including diet, physical activity, and sleep, have been studied in the context of children’s health. However, how these lifestyle factors contribute to the development of cognitive abilities, including spatial cognition, remains vastly understudied. One landmark in spatial cognitive development occurs between 2.5 and 3 years of age. For spatial orientation at that age, children learn to use allocentric reference frames (using spatial relations between objects as the primary reference frame) in addition to, the already acquired, egocentric reference frames (using one’s own body as the primary reference frame). In the current virtual reality study in a sample of 30–36-month-old toddlers (N = 57), we first demonstrated a marginally significant developmental shift in spatial orientation. Specifically, task performance with allocentric performance increased relative to egocentric performance (ηp2 = 0.06). Next, we explored a variety of lifestyle factors, including diet, in relation to task performance, to explain individual differences. Screen time and gestational weight gain of the mother were negatively associated with spatial task performance. The findings presented here can be used to guide future confirmatory studies about the role of lifestyle factors in the development of spatial cognition.

Down syndrome (DS, Trisomy 21) and Williams syndrome (WS) are two neurodevelopmental disorders of genetic origin that are accompanied by mild to moderate intellectual disability but exhibit distinct cognitive profiles. In this review we discuss our recent work characterizing the real-world spatial learning and memory abilities of adult individuals with DS and WS. We used several different paradigms in which participants locomote freely and have access to coherent input from all sensory modalities to investigate their fundamental egocentric (body-centered or viewpoint-dependent) and allocentric (world-centered or viewpoint-independent) spatial abilities. We found unequivocal evidence that most individuals with DS exhibit low-resolution egocentric and allocentric spatial learning and memory abilities similar to typically developing (TD) children in the same mental age range. In contrast, most individuals with DS exhibit impaired high-resolution allocentric spatial learning and facilitated response learning as compared to TD children. In comparison, whereas most individuals with WS also exhibit facilitated response learning, their low-resolution allocentric spatial learning and memory abilities are severely impaired as compared to both TD children and individuals with DS. Together with work from other laboratories using real-world or virtual reality paradigms, these findings indicate that in order to navigate in their environment most individuals with DS may use either egocentric route learning that does not integrate individual landmarks, or a low-resolution allocentric spatial representation that encodes the relationships between different locations (i.e., cognitive mapping). In contrast, since most individuals with WS are unable to build or use a low-resolution allocentric or configural representation of the environment they may use visually and verbally encoded landmarks as beacons to learn routes. Finally, we discuss the main neural structures implicated in these different spatial processes and explain how the relative preservation or impairment of specific brain functions may engender the unique cognitive profiles observed in individuals with these neurodevelopmental disorders.

Philosophy of perception is guilty of focusing on the perception of far space, neglecting the possibility that the perception of the space immediately surrounding the body, which is known as peripersonal space, displays different properties. Peripersonal space is the space in which the world is literally at hand for interaction. It is also the space in which the world can become threatening and dangerous, requiring protective behaviours. Recent research in cognitive neuroscience has yielded a vast array of discoveries on the multisensory and sensorimotor specificities of the processing of peripersonal space. Yet very little has been done on their philosophical implications. Here I will raise the following question: in what manner does the visual experience of a big rock close to my foot differ from the visual experience of the moon in the sky? [ABSTRACT FROM AUTHOR]

• Multiple reference frames are often available to animals in paradigms extensively used to study spatial learning. • Unaccounted reference frames can manifest as confounding factors, cause spurious associations and invalid inferences. • Directional learning predominates over place learning in widely used paradigms such as the Morris water maze and cross-maze. • We propose a decision-algorithm that serves as an example of how to approach the problem with multiple reference frames. • Hippocampus mediates complex egocentric learning whereas its role in response learning and path integration is controversial. One major challenge in animal research on spatial learning and memory pertains to designing methods to dissociate spatial strategies (allocentric vs. egocentric). This is crucial for understanding the underlying cognitive processes and neural circuits that are recruited in navigational tasks. Taking the egocentric reference frames as a starting point, this review argues that in many extensively used spatial paradigms, multiple spatial reference frames are often available to the animals but remain unaccounted for. We discuss the implications this has for the inferences that can be made and propose a decision-algorithm to construct spatial learning paradigms that can reduce the influence of these confounding variables. Furthermore, with these considerations in mind, we review the role of the hippocampus in egocentric navigation forms, i.e. in response learning, egocentric sequential learning and path integration. This choice is based on the controversy surrounding the role of hippocampus in these spatial paradigms. We discuss the possible methodological confounders that may explain the inconclusive results. [ABSTRACT FROM AUTHOR]

Down syndrome (DS, Trisomy 21) and Williams syndrome (WS) are two neurodevelopmental disorders of genetic origin that are accompanied by mild to moderate intellectual disability but exhibit distinct cognitive profiles. In this review we discuss our recent work characterizing the real-world spatial learning and memory abilities of adult individuals with DS and WS. We used several different paradigms in which participants locomote freely and have access to coherent input from all sensory modalities to investigate their fundamental egocentric (body-centered or viewpoint-dependent) and allocentric (world-centered or viewpoint-independent) spatial abilities. We found unequivocal evidence that most individuals with DS exhibit low-resolution egocentric and allocentric spatial learning and memory abilities similar to typically developing (TD) children in the same mental age range. In contrast, most individuals with DS exhibit impaired high-resolution allocentric spatial learning and facilitated response learning as compared to TD children. In comparison, whereas most individuals with WS also exhibit facilitated response learning, their low-resolution allocentric spatial learning and memory abilities are severely impaired as compared to both TD children and individuals with DS. Together with work from other laboratories using real-world or virtual reality paradigms, these findings indicate that in order to navigate in their environment most individuals with DS may use either egocentric route learning that does not integrate individual landmarks, or a low-resolution allocentric spatial representation that encodes the relationships between different locations (i.e., cognitive mapping). In contrast, since most individuals with WS are unable to build or use a low-resolution allocentric or configural representation of the environment they may use visually and verbally encoded landmarks as beacons to learn routes. Finally, we discuss the main neural structures implicated in these different spatial processes and explain how the relative preservation or impairment of specific brain functions may engender the unique cognitive profiles observed in individuals with these neurodevelopmental disorders. [ABSTRACT FROM AUTHOR]

Representations of space in mind are crucial for navigation, facilitating processes such as remembering landmark locations, understanding spatial relationships between objects, and integrating routes. A significant problem, however, is the lack of consensus on how these representations are encoded and stored in memory. Specifically, the nature of egocentric and allocentric frames of reference in human memory is widely debated. Yet, in recent investigations of the spatial domain across the lifespan, these distinctions in mnemonic spatial frames of reference have identified age‐related impairments. In this review, we survey the ways in which different terms related to spatial representations in memory have been operationalized in past aging research and suggest a taxonomy to provide a common language for future investigations and theoretical discussion. This article is categorized under:Psychology > MemoryNeuroscience > CognitionPsychology > Development and Aging [ABSTRACT FROM AUTHOR]

Existing methods for egocentric activity recognition are mostly based on extracting motion characteristics from videos. On the other hand, ubiquity of wearable sensors allow acquisition of information from different sources. Although the increase in sensor diversity brings out the need for adaptive fusion, most of the studies use pre-determined weights for each source. In addition, there are a limited number of studies making use of optical, audio and wearable sensors. In this work, we propose a new framework that adaptively weighs the visual, audio and sensor features in relation to their discriminative abilities. For that purpose, multi-kernel learning (MKL) is used to fuse multi-modal features where the feature and kernel selection/weighing and recognition tasks are performed concurrently. Audio-visual information is used in association with the data acquired from wearable sensors since they hold information on different aspects of activities and help building better models. The proposed framework can be used with different modalities to improve the recognition accuracy and easily be extended with additional sensors. The results show that using multi-modal features with MKL outperforms the existing methods. [ABSTRACT FROM AUTHOR]

Egocentric representations of external items are essential for spatial navigation and memory. Here, we explored the neural mechanisms underlying egocentric processing in the retrosplenial cortex (RSC), a pivotal area for memory and navigation. Using one-photon and two-photon calcium imaging, we identified egocentric tuning for environment boundaries in dendrites, spines, and somas of RSC neurons (egocentric boundary cells) in the open-field task. Dendrites with egocentric tuning tended to have similarly tuned spines. We further identified egocentric neurons representing landmarks in a virtual navigation task or remembered cue location in a goal-oriented task, respectively. These neurons formed an independent population with egocentric boundary cells, suggesting that dedicated neurons with microscopic clustering of functional inputs shaped egocentric boundary processing in RSC and that RSC adopted a labeled line code with distinct classes of egocentric neurons responsible for representing different items in specific behavioral contexts, which could lead to efficient and flexible computation. [Display omitted] • RSC dendrites with egocentric boundary tuning had more similarly tuned spines • Some RSC cells functioned as egocentric landmark cells • Egocentric landmark dendrites had more similarly tuned spines • Independent cell sets were recruited for items with sufficiently different demands To study how distinct items are represented by the egocentric representation system, Cheng et al. show that retrosplenial cortex neurons demonstrated microscopic clustering of functional inputs at the synaptic level, and independent populations of cells were recruited to represent items in sufficiently different contexts. [ABSTRACT FROM AUTHOR]

While the widely studied allocentric spatial representation holds a special status in neuroscience research, its exact nature and neural underpinnings continue to be the topic of debate, particularly in humans. Here, based on a review of human behavioral research, we argue that allocentric representations do not provide the kind of map-like, metric representation one might expect based on past theoretical work. Instead, we suggest that almost all tasks used in past studies involve a combination of egocentric and allocentric representation, complicating both the investigation of the cognitive basis of an allocentric representation and the task of identifying a brain region specifically dedicated to it. Indeed, as we discuss in detail, past studies suggest numerous brain regions important to allocentric spatial memory in addition to the hippocampus, including parahippocampal, retrosplenial, and prefrontal cortices. We thus argue that although allocentric computations will often require the hippocampus, particularly those involving extracting details across temporally specific routes, the hippocampus is not necessary for all allocentric computations. We instead suggest that a non-aggregate network process involving multiple interacting brain areas, including hippocampus and extra-hippocampal areas such as parahippocampal, retrosplenial, prefrontal, and parietal cortices, better characterizes the neural basis of spatial representation during navigation. According to this model, an allocentric representation does not emerge from the computations of a single brain region (i.e., hippocampus) nor is it readily decomposable into additive computations performed by separate brain regions. Instead, an allocentric representation emerges from computations partially shared across numerous interacting brain regions. We discuss our non-aggregate network model in light of existing data and provide several key predictions for future experiments.

Every individual has a different interpretation in understanding religion because of internal factors (differences in background, education, religious experience, environment that shapes character, and socio-economic status). The pattern of individuals understanding on religion is believed to be inseparable from the basic doctrine they acquired. Although, not infrequently the religion concepts originating from the doctrine is interfered by imagination and reality based on spiritual experiences. This research aims to determine the understanding and thinking development of the early childhood age 3-6 years old about religion interpretation. This research was a qualitative descriptive research. The research subjects were early childhood at Rumah Ibu Kindergarten, Sleman, and Yogyakarta. Data collection techniques were observations, in-depth interviews, and documentation. Data analysis were data reduction, data display and drawing conclusion and verification. The results of the research indicate that; 1) Religion is described by early childhood with symbols and worship rituals. Regarding the divine concept, children still describe God as egocentric and anthropomorphic, followed by God’s characteristics. 2) The interpretation of early childhood about religion is predominantly influenced by experiences, parents, teachers, and the surrounding environment. The findings of this research suggest that the cultivation of godliness must be able to develop children's fantasies about the infinite nature of God, and also the children’s love and obedience to God associated to the problems that are close to the children's live. Therefore, in addition to develop the fantasy power, factual learning is needed.

Older adults typically perform worse on spatial navigation tasks, although whether this is due to degradation of memory or an impairment in using specific strategies has yet to be determined. An issue with some past studies is that older adults are tested on desktop-based virtual reality: a technology many report lacking familiarity with. Even when controlling for familiarity, these paradigms reduce the information-rich, three-dimensional experience of navigating to a simple two-dimensional task that utilizes a mouse and keyboard (or joystick) as means for ambulation. Here, we utilize a wireless head-mounted display and free ambulation to create a fully immersive virtual Morris water maze in which we compare the navigation of older and younger adults. Older and younger adults learned the locations of hidden targets from same and different start points. Across different conditions tested, older adults remembered target locations less precisely compared to younger adults. Importantly, however, they performed comparably from the same viewpoint as a switched viewpoint, suggesting that they could generalize their memory for the location of a hidden target given a new point of view. When we implicitly moved one of the distal cues to determine whether older adults used an allocentric (multiple landmarks) or beaconing (single landmark) strategy to remember the hidden target, both older and younger adults showed comparable degrees of reliance on allocentric and beacon cues. These findings support the hypothesis that while older adults have less precise spatial memories, they maintain the ability to utilize various strategies when navigating.

Converging evidence has established that positive concepts presented on a computer screen are associated with upper regions of space, and negative concepts with a lower region of space. One explanation for this is that understanding positive or negative concepts requires the re-experiencing of direction, whereby “happy is up” and “sad is down.” However, it is unclear how the regions of space are encoded in these paradigms, space can be encoded in relation to oneself (egocentrically) or in object centred coordinates that are independent of oneself (exocentrically). The current study compares exocentric and egocentric coding of space, using a variation of the Meier and Robinson (2004) paradigm. Participants were asked to evaluate valenced concepts in either the upper or lower half of the screen. Spatial primes were used such that the concepts were preceded by either an upwards or a downwards eye movement. Exocentric coding of space in this paradigm was the computer screen, whilst egocentric coding was the eye movement used to access the top or bottom of the screen. It was proposed that egocentric coding of space, being coded in the body, provides evidence of a stronger relationship between the original bodily state of ‘up’ or ‘down’ and subsequent simulation. However, significant results supported an exocentric coding of space, with faster responses to positive concepts in the upper half of the screen, and to negative concepts in the lower half, irrespective of the direction of the eye movement preceding it. The implications of this for embodied cognition are discussed.

Older adults typically perform worse on spatial navigation tasks, although whether this is due to degradation of memory or an impairment in using specific strategies has yet to be determined. An issue with some past studies is that older adults are tested on desktop-based virtual reality: a technology many report lacking familiarity with. Even when controlling for familiarity, these paradigms reduce the information-rich, three-dimensional experience of navigating to a simple two-dimensional task that utilizes a mouse and keyboard (or joystick) as means for ambulation. Here, we utilize a wireless head-mounted display and free ambulation to create a fully immersive virtual Morris water maze in which we compare the navigation of older and younger adults. Older and younger adults learned the locations of hidden targets from same and different start points. Across different conditions tested, older adults remembered target locations less precisely compared to younger adults. Importantly, however, they performed comparably from the same viewpoint as a switched viewpoint, suggesting that they could generalize their memory for the location of a hidden target given a new point of view. When we implicitly moved one of the distal cues to determine whether older adults used an allocentric (multiple landmarks) or beaconing (single landmark) strategy to remember the hidden target, both older and younger adults showed comparable degrees of reliance on allocentric and beacon cues. These findings support the hypothesis that while older adults have less precise spatial memories, they maintain the ability to utilize various strategies when navigating. [ABSTRACT FROM AUTHOR]

Cognitive biases for encoding spatial information (orientation strategies) in relation to self (egocentric) or landmarks (allocentric) differ between species or populations according to the habitats they occupy. Whether biases in orientation strategy determine early habitat selection or if individuals adapt their biases following experience is unknown. We determined orientation strategies of pheasants, Phasianus colchicus, using a dual‐strategy maze with an allocentric probe trial, before releasing them (n = 20) into a novel landscape, where we monitored their movement and habitat selection. In general, pheasants selected for woodland over non‐woodland habitat, but allocentric‐biased individuals exhibited weaker avoidance of non‐woodland habitat, where we expected allocentric navigation to be more effective. Sex did not influence selection but was associated with speed and directional persistence in non‐woodland habitat. Our results suggest that an individual's habitat selection is associated with inherent cognitive bias in early life, but it is not yet clear what advantages this may offer. [ABSTRACT FROM AUTHOR]

The most used frames of reference in spatial memory, which allows us to move through the environment, are the egocentric, related to one's own perspective, and the allocentric, based on environmental cues. Although many tasks have been proposed, those that evaluate the two frames of reference separately and compare adults and children are scarce. Our aim was to assess egocentric and allocentric spatial orientation in young children and young adults, comparing between ages, frames of reference and gender. The Egocentric and Allocentric Spatial Memory tests were used. Adults performed better than children on both tasks. Children performed equally in both frames of reference, but adults were more efficient on the allocentric test. Gender did not seem relevant in the performance of either group. Overall, egocentric and allocentric spatial memory are not fully developed at the age of 7 and children do not master any strategy above the other. Highlights: Do school‐aged children reach adults performance in egocentric and allocentric spatial memory?Two experimental tasks, Egocentric and Allocentric Spatial Memory tests, were used for assessment. Significant differences were found between children from 5‐to‐7 years and adults.Egocentric and allocentric frameworks are not fully developed at 7 years. Children may not rely on one specific framework for their orientation. [ABSTRACT FROM AUTHOR]

Williams (WS) and Down (DS) syndromes are neurodevelopmental disorders with distinct genetic origins and different spatial memory profiles. In real-world spatial memory tasks, where spatial information derived from all sensory modalities is available, individuals with DS demonstrate low-resolution spatial learning capacities consistent with their mental age, whereas individuals with WS are severely impaired. However, because WS is associated with severe visuo-constructive processing deficits, it is unclear whether their impairment is due to abnormal visual processing or whether it reflects an inability to build a cognitive map. Here, we tested whether blindfolded individuals with WS or DS, and typically developing (TD) children with similar mental ages, could use path integration to perform an egocentric homing task and return to a starting point. We then evaluated whether they could take shortcuts and navigate along never-traveled trajectories between four objects while blindfolded, thus demonstrating the ability to build a cognitive map. In the homing task, 96% of TD children, 84% of participants with DS and 44% of participants with WS were able to use path integration to return to their starting point consistently. In the cognitive mapping task, 64% of TD children and 74% of participants with DS were able to take shortcuts and use never-traveled trajectories, the hallmark of cognitive mapping ability. In contrast, only one of eighteen participants with WS demonstrated the ability to build a cognitive map. These findings are consistent with the view that hippocampus-dependent spatial learning is severely impacted in WS, whereas it is relatively preserved in DS.

Background: Cognitive deficits are common in early multiple sclerosis (MS), however, spatial navigation changes and their associations with brain pathology remain poorly understood. Objective: To characterize the profile of spatial navigation changes in two main navigational strategies, egocentric (self-centred) and allocentric (world-centred), and their associations with demyelinating and neurodegenerative changes in early MS. Methods: Participants with early MS after the first clinical event (n = 51) and age-, gender- and education-matched controls (n = 42) underwent spatial navigation testing in a real-space human analogue of the Morris water maze task, comprehensive neuropsychological assessment, and MRI brain scan with voxel-based morphometry and volumetric analyses. Results: The early MS group had lower performance in the egocentric (p = 0.010), allocentric (p = 0.004) and allocentric-delayed (p = 0.038) navigation tasks controlling for age, gender and education. Based on the applied criteria, lower spatial navigation performance was present in 26–29 and 33–41% of the participants with early MS in the egocentric and the allocentric task, respectively. Larger lesion load volume in cortical, subcortical and cerebellar regions (ß ≥ 0.29; p ≤ 0.032) unlike brain atrophy was associated with less accurate allocentric navigation performance. Conclusion: Lower spatial navigation performance is present in up to 41% of the participants with early MS. Demyelinating lesions in early MS may disrupt neural network forming the basis of allocentric navigation. [ABSTRACT FROM AUTHOR]

Objectives: The present study evaluated the reciprocal temporal associations between one's subjective age (or felt age) and one's social relations in the adult day care center (ADCC) over two waves of data collection, spread about 1 year apart. Method: Participants from four ADCCs in Israel were approached in 2017 and repeatedly, in 2018 (N = 224 in Wave 1 and N = 259 in Wave 2). The ADCC social network included both outgoing ties of familiar relationships with other ADCC members as reported by the respondent (out-degree centrality) and ingoing ties, based on reports of other ADCC members who were familiar with the respondent (in-degree centrality). Results: Out-degree and in-degree centrality at baseline were not associated with change in subjective age. Subjective age at the first time point was not associated with change in out-degree centrality, but it was negatively associated with change in in-degree centrality. Even after controlling for sociodemographic and health variables, adults who felt younger were subsequently cited by more ADCC members. Conclusions: The findings stress the importance of subjective age to one's relationship in the ADCC. It is suggested that a younger subjective age is a desired quality in the ADCC. [ABSTRACT FROM AUTHOR]

Animals can use different types of information for navigation. Domestic chicks (Gallus gallus) prefer to use local features as a beacon over spatial relational information. However, the role of egocentric navigation strategies is less understood. Here, we tested domestic chicks' egocentric and allocentric orientation abilities in a large circular arena. In experiment 1, we investigated whether domestic chicks possess a side bias during viewpoint-dependent egocentric orientation, revealing facilitation for targets on the chicks' left side. Experiment 2 showed that local features are preferred over viewpoint-dependent egocentric information when the two conflict. Lastly, in experiment 3, we found that in a situation where there is a choice between egocentric and allocentric spatial relational information provided by free-standing objects, chicks preferentially rely on egocentric information. We conclude that chicks orient according to a hierarchy of cues, in which the use of the visual appearance of an object is the dominant strategy, followed by viewpoint-dependent egocentric information and finally by spatial relational information., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

Williams (WS) and Down (DS) syndromes are neurodevelopmental disorders with distinct genetic origins and different spatial memory profiles. In real-world spatial memory tasks, where spatial information derived from all sensory modalities is available, individuals with DS demonstrate low-resolution spatial learning capacities consistent with their mental age, whereas individuals with WS are severely impaired. However, because WS is associated with severe visuo-constructive processing deficits, it is unclear whether their impairment is due to abnormal visual processing or whether it reflects an inability to build a cognitive map. Here, we tested whether blindfolded individuals with WS or DS, and typically developing (TD) children with similar mental ages, could use path integration to perform an egocentric homing task and return to a starting point. We then evaluated whether they could take shortcuts and navigate along never-traveled trajectories between four objects while blindfolded, thus demonstrating the ability to build a cognitive map. In the homing task, 96% of TD children, 84% of participants with DS and 44% of participants with WS were able to use path integration to return to their starting point consistently. In the cognitive mapping task, 64% of TD children and 74% of participants with DS were able to take shortcuts and use never-traveled trajectories, the hallmark of cognitive mapping ability. In contrast, only one of eighteen participants with WS demonstrated the ability to build a cognitive map. These findings are consistent with the view that hippocampus-dependent spatial learning is severely impacted in WS, whereas it is relatively preserved in DS. [ABSTRACT FROM AUTHOR]

Spatial representation in the haptic domain has been shown to be prone to systematic errors. When participants are asked to make two bars haptically parallel, their performance deviates from what would be veridically parallel. This is hypothesized to be caused by the bias of the egocentric reference frame. Stimulating the use of an allocentric reference frame has previously been shown to improve performance in haptic parallelity matching. The aim of the current study was to investigate the influence of action video game experience on parallelity performance. We hypothesized that participants who extensively play action video games with a so-called 'bird's-eye view' are likely to process spatial information more allocentrically, resulting in better performance in haptic parallelity matching. This was tested in two groups of male participants, 10 participants with extensive action video gaming experience (AVGPs) and 10 participants without or hardly any action video gaming experience (NAVGPs). Additionally, the effect of visual–haptic practice on haptic parallelity performance was tested. In the haptic blocks, blindfolded participants had to feel the orientation of a reference bar with their non-dominant hand and had to match this orientation on a test bar with their dominant hand. In subsequent visual–haptic blocks, they had full view of the set-up and visually paralleled both bars. As hypothesized, AVGPs performed significantly better in haptic blocks than NAVGPs. Visual–haptic practice resulted in significantly better performance in subsequent haptic blocks in both groups. These results suggest that playing action video games might enhance haptic spatial representation, although a causative relationship still needs to be established. [ABSTRACT FROM AUTHOR]

Human description of the surrounding world may spontaneously rely on others' perspective, which is a crucial component of social cognition. In five studies, participants were asked to describe the spatial relations between objects in visual scenes including, or not, other agents. In Experiment 1, a substantial proportion of participants used an other-centered perspective in the presence of another agent, replicating classical findings. To our own surprise, we also observed that an even greater number of participants used an other-centered perspective when the human agent was replaced by an armchair. In order to explore this phenomenon, Experiments 2 to 5 compared the respective strength of chair-centered and agent-centered perspectives and/or set them into conflict. A significant proportion of participants spontaneously took the seat's perspective even when it may not be sat on (Experiments 3 and 4) and even when the seat was not referred to (Experiments 4 and 5). Altogether, these findings suggest that perspective taking may spontaneously apply to inanimate objects. These results question whether such tendencies originate from social cognitive skills—as classically assumed—or reveal a nonsocial phenomenon. Future works should specifically test the widely assumed social nature of spontaneous perspective-taking. [ABSTRACT FROM AUTHOR]

Human adults can optimally combine vision with self-motion to facilitate navigation. In the absence of visual input (e.g., dark environments and visual impairments), sensory substitution devices (SSDs), such as The vOICe or BrainPort, which translate visual information into auditory or tactile information, could be used to increase navigation precision when integrated together or with self-motion. In Experiment 1, we compared and assessed together The vOICe and BrainPort in aerial maps task performed by a group of sighted participants. In Experiment 2, we examined whether sighted individuals and a group of visually impaired (VI) individuals could benefit from using The vOICe, with and without self-motion, to accurately navigate a three-dimensional (3D) environment. In both studies, 3D motion tracking data were used to determine the level of precision with which participants performed two different tasks (an egocentric and an allocentric task) and three different conditions (two unisensory conditions and one multisensory condition). In Experiment 1, we found no benefit of using the devices together. In Experiment 2, the sighted performance during The vOICe was almost as good as that for self-motion despite a short training period, although we found no benefit (reduction in variability) of using The vOICe and self-motion in combination compared to the two in isolation. In contrast, the group of VI participants did benefit from combining The vOICe and self-motion despite the low number of trials. Finally, while both groups became more accurate in their use of The vOICe with increased trials, only the VI group showed an increased level of accuracy in the combined condition. Our findings highlight how exploiting non-visual multisensory integration to develop new assistive technologies could be key to help blind and VI persons, especially due to their difficulty in attaining allocentric information.

Abstract Introduction Spatial orientation relies mainly on two frameworks. The egocentric depends on our own position and point of view. The allocentric relies on remembering, recalling, and recognizing environmental stimuli called landmarks. The aim of this study was to analyze the egocentric and allocentric spatial memory performance in children of different ages using two experimental memory card‐placing tasks. We also aimed to examine relationships between spatial memory and other cognitive, physiological, and behavioral factors that, potentially, could be associated with spatial memory performance. Those were other visuospatial functions, the regular behavior of the child, cortisol levels, and daily life spatial memory. Methods We assessed 62 children (5, 6, and 7 years) using card‐placing tasks. We used RIST for IQ evaluation and subtest from NEPSY‐II for visuospatial ability assessment. Collection of saliva sample was carried out for cortisol analysis. Parents completed BASC questionnaire for behavioral evaluation and ECM‐Q questionnaire for daily life spatial memory evaluation. Results Our results showed that older children performed better on mental rotation. Directionality, map interpretation, and daily memory were directly associated with both egocentric and allocentric orientation. Egocentric performance was positively related to leadership abilities but negatively to depression and atypicality, while allocentric performance was directly associated with adaptive behavior but inversely with hyperactivity. Finally, cortisol values were positively associated with allocentric performance. Conclusions Our study shows the development of different spatial abilities between 5 and 7 years, as well as the relationship between orientation performance, visuospatial skills, behavior, and cortisol.

Path integration spatial navigation processes are emerging as promising cognitive markers for prodromal and clinical Alzheimer’s disease (AD). However, such path integration changes have been less explored in Vascular Cognitive Impairment (VCI), despite neurovascular change being a major contributing factor to dementia and potentially AD. In particular, the sensitivity and specificity of path integration impairments in VCI compared to AD is unclear. In the current pilot study, we explore path integration performance in early-stage AD and VCI patient groups and hypothesize that: (i) medial parietal mediated egocentric processes will be more affected in VCI; and (ii) medial temporal mediated allocentric processes will be more affected in AD. This cross-sectional study included early-stage VCI patients (n = 9), AD patients (n = 10) and healthy age-matched controls (n = 20). All participants underwent extensive neuropsychological testing, as well as spatial navigation testing. The spatial navigation tests included the virtual reality “Supermarket” task assessing egocentric (body-based) and allocentric (map-based) navigation as well as the “Clock Orientation” test assessing egocentric and path integration processes. Results showed that egocentric integration processes are only impaired in VCI, potentially distinguishing it from AD. However, in contrast to our prediction, allocentric integration was not more impaired in AD compared to VCI. These preliminary findings suggest limited specificity of allocentric integration deficits between VCI and AD. By contrast, egocentric path integration deficits emerge as more specific to VCI, potentially allowing for more specific diagnostic and treatment outcome measures for vascular impairment in dementia.

The goal of the present study was to investigate spatial memory in a group of patients with amnesia due to Korsakoff’s syndrome (KS). We used a virtual spatial memory task that allowed us to separate the use of egocentric and allocentric spatial reference frames to determine object locations. Research investigating the ability of patients with Korsakoff’s amnesia to use different reference frames is scarce and it remains unclear whether these patients are impaired in using ego- and allocentric reference frames to the same extent. Twenty Korsakoff patients and 24 matched controls watched an animation of a bird flying in one of three trees standing in a virtual environment. After the bird disappeared, the camera turned around, by which the trees were briefly out of sight and then turned back to the center of the environment. Participants were asked in which tree the bird was hiding. In half of the trials, a landmark was shown. Half of the trials required an immediate response whereas in the other half a delay of 10 s was present. Patients performed significantly worse than controls. For all participants trials with a landmark were easier than without a landmark and trials without a delay were easier than with a delay. While controls were above chance on all trials patients were at chance in allocentric trials without a landmark present and with a memory delay. Patients showed no difference in the ego- and the allocentric condition. Together the findings suggest that despite the amnesia, spatial memory and especially the use of ego- and allocentric reference frames in Korsakoff patients are spared.

Abstract Hand segmentation is one of the most fundamental and crucial steps for egocentric human-computer interaction. The special egocentric view brings new challenges to hand segmentation tasks, such as the unpredictable environmental conditions. The performance of traditional hand segmentation methods depend on abundant manually labeled training data. However, these approaches do not appropriately capture the whole properties of egocentric human-computer interaction for neglecting the user-specific context. It is only necessary to build a personalized hand model of the active user. Based on this observation, we propose an online-learning hand segmentation approach without using manually labeled data for training. Our approach consists of top-down classifications and bottom-up optimizations. More specifically, we divide the segmentation task into three parts, a frame-level hand detection which detects the presence of the interactive hand using motion saliency and initializes hand masks for online learning, a superpixel-level hand classification which coarsely segments hand regions from which stable samples are selected for next level, and a pixel-level hand classification which produces a fine-grained hand segmentation. Based on the pixel-level classification result, we update the hand appearance model and optimize the upper layer classifier and detector. This online-learning strategy makes our approach robust to varying illumination conditions and hand appearances. Experimental results demonstrate the robustness of our approach.

The dissociation between egocentric and allocentric reference frames is well established. Spatial coding relative to oneself has been associated with a brain network distinct from spatial coding using a cognitive map independently of the actual position. These differences were, however, revealed by a variety of tasks from both static conditions, using a series of images, and dynamic conditions, using movements through space. We aimed to clarify how these paradigms correspond to each other concerning the neural correlates of the use of egocentric and allocentric reference frames. We review here studies of allocentric and egocentric judgments used in static two- and three-dimensional tasks and compare their results with the findings from spatial navigation studies. We argue that neural correlates of allocentric coding in static conditions but using complex three-dimensional scenes and involving spatial memory of participants resemble those in spatial navigation studies, while allocentric representations in two-dimensional tasks are connected with other perceptual and attentional processes. In contrast, the brain networks associated with the egocentric reference frame in static two-dimensional and three-dimensional tasks and spatial navigation tasks are, with some limitations, more similar. Our review demonstrates the heterogeneity of experimental designs focused on spatial reference frames. At the same time, it indicates similarities in brain activation during reference frame use despite this heterogeneity. [ABSTRACT FROM AUTHOR]

We introduce a method for egocentric videoconferencing that enables hands-free video calls, for instance by people wearing smart glasses or other mixed-reality devices. Videoconferencing portrays valuable non-verbal communication and face expression cues, but usually requires a front-facing camera. Using a frontal camera in a hands-free setting when a person is on the move is impractical. Even holding a mobile phone camera in the front of the face while sitting for a long duration is not convenient. To overcome these issues, we propose a low-cost wearable egocentric camera setup that can be integrated into smart glasses. Our goal is to mimic a classical video call, and therefore, we transform the egocentric perspective of this camera into a front facing video. To this end, we employ a conditional generative adversarial neural network that learns a transition from the highly distorted egocentric views to frontal views common in videoconferencing. Our approach learns to transfer expression details directly from the egocentric view without using a complex intermediate parametric expressions model, as it is used by related face reenactment methods. We successfully handle subtle expressions, not easily captured by parametric blendshape-based solutions, e.g., tongue movement, eye movements, eye blinking, strong expressions and depth varying movements. To get control over the rigid head movements in the target view, we condition the generator on synthetic renderings of a moving neutral face. This allows us to synthesis results at different head poses. Our technique produces temporally smooth video-realistic renderings in real-time using a video-to-video translation network in conjunction with a temporal discriminator. We demonstrate the improved capabilities of our technique by comparing against related state-of-the art approaches. [ABSTRACT FROM AUTHOR]

In everyday life, our brain constantly builds spatial representations of the objects surrounding us. Many studies have investigated the nature of these spatial representations. It is well established that we use allocentric information in real-time and memory-guided movements. Most studies relied on small-scale and static experiments, leaving it unclear whether similar paradigms yield the same results on a larger scale using dynamic objects. We created a virtual reality task that required participants to encode the landing position of a virtual ball thrown by an avatar. Encoding differed in the nature of the task in that it was either purely perceptual ("view where the ball landed while standing still"—Experiment 1) or involved an action ("intercept the ball with the foot just before it lands"—Experiment 2). After encoding, participants were asked to place a real ball at the remembered landing position in the virtual scene. In some trials, we subtly shifted either the thrower or the midfield line on a soccer field to manipulate allocentric coding of the ball's landing position. In both experiments, we were able to replicate classic findings from small-scale experiments and to generalize these results to different encoding tasks (perception vs. action) and response modes (reaching vs. walking-and-placing). Moreover, we found that participants preferably encoded the ball relative to the thrower when they had to intercept the ball, suggesting that the use of allocentric information is determined by the encoding task by enhancing task-relevant allocentric information. Our findings indicate that results previously obtained from memory-guided reaching are not restricted to small-scale movements, but generalize to whole-body movements in large-scale dynamic scenes. [ABSTRACT FROM AUTHOR]

Human adults can optimally combine vision with self-motion to facilitate navigation. In the absence of visual input (e.g., dark environments and visual impairments), sensory substitution devices (SSDs), such as The vOICe or BrainPort, which translate visual information into auditory or tactile information, could be used to increase navigation precision when integrated together or with self-motion. In Experiment 1, we compared and assessed together The vOICe and BrainPort in aerial maps task performed by a group of sighted participants. In Experiment 2, we examined whether sighted individuals and a group of visually impaired (VI) individuals could benefit from using The vOICe, with and without self-motion, to accurately navigate a three-dimensional (3D) environment. In both studies, 3D motion tracking data were used to determine the level of precision with which participants performed two different tasks (an egocentric and an allocentric task) and three different conditions (two unisensory conditions and one multisensory condition). In Experiment 1, we found no benefit of using the devices together. In Experiment 2, the sighted performance during The vOICe was almost as good as that for self-motion despite a short training period, although we found no benefit (reduction in variability) of using The vOICe and self-motion in combination compared to the two in isolation. In contrast, the group of VI participants did benefit from combining The vOICe and self-motion despite the low number of trials. Finally, while both groups became more accurate in their use of The vOICe with increased trials, only the VI group showed an increased level of accuracy in the combined condition. Our findings highlight how exploiting non-visual multisensory integration to develop new assistive technologies could be key to help blind and VI persons, especially due to their difficulty in attaining allocentric information. [ABSTRACT FROM AUTHOR]

Introduction: Spatial orientation relies mainly on two frameworks. The egocentric depends on our own position and point of view. The allocentric relies on remembering, recalling, and recognizing environmental stimuli called landmarks. The aim of this study was to analyze the egocentric and allocentric spatial memory performance in children of different ages using two experimental memory card‐placing tasks. We also aimed to examine relationships between spatial memory and other cognitive, physiological, and behavioral factors that, potentially, could be associated with spatial memory performance. Those were other visuospatial functions, the regular behavior of the child, cortisol levels, and daily life spatial memory. Methods: We assessed 62 children (5, 6, and 7 years) using card‐placing tasks. We used RIST for IQ evaluation and subtest from NEPSY‐II for visuospatial ability assessment. Collection of saliva sample was carried out for cortisol analysis. Parents completed BASC questionnaire for behavioral evaluation and ECM‐Q questionnaire for daily life spatial memory evaluation. Results: Our results showed that older children performed better on mental rotation. Directionality, map interpretation, and daily memory were directly associated with both egocentric and allocentric orientation. Egocentric performance was positively related to leadership abilities but negatively to depression and atypicality, while allocentric performance was directly associated with adaptive behavior but inversely with hyperactivity. Finally, cortisol values were positively associated with allocentric performance. Conclusions: Our study shows the development of different spatial abilities between 5 and 7 years, as well as the relationship between orientation performance, visuospatial skills, behavior, and cortisol. [ABSTRACT FROM AUTHOR]

Path integration spatial navigation processes are emerging as promising cognitive markers for prodromal and clinical Alzheimer's disease (AD). However, such path integration changes have been less explored in Vascular Cognitive Impairment (VCI), despite neurovascular change being a major contributing factor to dementia and potentially AD. In particular, the sensitivity and specificity of path integration impairments in VCI compared to AD is unclear. In the current pilot study, we explore path integration performance in early-stage AD and VCI patient groups and hypothesize that: (i) medial parietal mediated egocentric processes will be more affected in VCI; and (ii) medial temporal mediated allocentric processes will be more affected in AD. This cross-sectional study included early-stage VCI patients (n = 9), AD patients (n = 10) and healthy age-matched controls (n = 20). All participants underwent extensive neuropsychological testing, as well as spatial navigation testing. The spatial navigation tests included the virtual reality "Supermarket" task assessing egocentric (body-based) and allocentric (map-based) navigation as well as the "Clock Orientation" test assessing egocentric and path integration processes. Results showed that egocentric integration processes are only impaired in VCI, potentially distinguishing it from AD. However, in contrast to our prediction, allocentric integration was not more impaired in AD compared to VCI. These preliminary findings suggest limited specificity of allocentric integration deficits between VCI and AD. By contrast, egocentric path integration deficits emerge as more specific to VCI, potentially allowing for more specific diagnostic and treatment outcome measures for vascular impairment in dementia. [ABSTRACT FROM AUTHOR]

In addition to its role in visuospatial navigation and the generation of spatial representations, in recent years, the hippocampus has been proposed to support perceptual processes. This is especially the case where high‐resolution details, in the form of fine‐grained relationships between features such as angles between components of a visual scene, are involved. An unresolved question is how, in the visual domain, perspective‐changes are differentiated from allocentric changes to these perceived feature relationships, both of which may be argued to involve the hippocampus. We conducted functional magnetic resonance imaging of the brain response (corroborated through separate event‐related potential source‐localization) in a passive visuospatial oddball‐paradigm to examine to what extent the hippocampus and other brain regions process changes in perspective, or configuration of abstract, three‐dimensional structures. We observed activation of the left superior parietal cortex during perspective shifts, and right anterior hippocampus in configuration‐changes. Strikingly, we also found the cerebellum to differentiate between the two, in a way that appeared tightly coupled to hippocampal processing. These results point toward a relationship between the cerebellum and the hippocampus that occurs during perception of changes in visuospatial information that has previously only been reported with regard to visuospatial navigation. [ABSTRACT FROM AUTHOR]

The goal of the present study was to investigate spatial memory in a group of patients with amnesia due to Korsakoff's syndrome (KS). We used a virtual spatial memory task that allowed us to separate the use of egocentric and allocentric spatial reference frames to determine object locations. Research investigating the ability of patients with Korsakoff's amnesia to use different reference frames is scarce and it remains unclear whether these patients are impaired in using ego- and allocentric reference frames to the same extent. Twenty Korsakoff patients and 24 matched controls watched an animation of a bird flying in one of three trees standing in a virtual environment. After the bird disappeared, the camera turned around, by which the trees were briefly out of sight and then turned back to the center of the environment. Participants were asked in which tree the bird was hiding. In half of the trials, a landmark was shown. Half of the trials required an immediate response whereas in the other half a delay of 10 s was present. Patients performed significantly worse than controls. For all participants trials with a landmark were easier than without a landmark and trials without a delay were easier than with a delay. While controls were above chance on all trials patients were at chance in allocentric trials without a landmark present and with a memory delay. Patients showed no difference in the ego- and the allocentric condition. Together the findings suggest that despite the amnesia, spatial memory and especially the use of ego- and allocentric reference frames in Korsakoff patients are spared. [ABSTRACT FROM AUTHOR]

Aim: This study examined the contribution of the social network to one's sense of belonging to the community (SCB) in two different long‐term care settings: Continuing care retirement communities (CCRCs) and adult day care centers (ADCCs). Methods: Overall, 245 respondents participated in both waves of the study that were spaced about 1 year apart. Results: Results show that constraint in the social network (e.g., being socially invested in a single group of interconnected ties) is particularly detrimental for CCRC residents, but not for ADCC participants. Betweenness, defined as the number of shortest paths that pass through the focal person, was not significantly related to SCB. In addition, the size of the egocentric network, obtained through a name generator of a list of all potentially meaningful individuals identified by respondents, was directly correlated with SCB at follow‐up. Conclusions: The findings are discussed in light of differences between the two long‐term care settings and the different social network indicators examined in this study. [ABSTRACT FROM AUTHOR]

Introduction: Spatial navigation deficits are observed in Alzheimer's disease cross‐sectionally, but prediction of longitudinal clinical decline has been less examined. Methods: Cognitive mapping (CM) was assessed in 95 participants and route learning (RL) was assessed in 65 participants at baseline. Clinical progression over an average of 4 to 5 years was assessed using the clinical dementia rating (CDR) scale. Relative predictive ability was compared to episodic memory, hippocampus, and cerebrospinal fluid biomarkers (phosphorylated tau/amyloid β 42 (ptau181/Aβ42) ratio). Results: CM and RL were predictors of clinical progression (P's < 0.032). All measures, except RL‐Learning remained predictors with episodic memory in models (P's < 0.048). Only RL‐Retrieval remained a predictor when ptau181/Aβ42 was included (P < 0.001). CM interacted with hippocampus and ptau181/Aβ42 in prediction (P's < 0.013). CM, RL, and episodic memory evidenced strong diagnostic accuracy (area under the curve (AUC) = 0.894, 0.794, and 0.735, respectively); CM tended to perform better than episodic memory (P = 0.056). Discussion: Baseline spatial navigation performance may be appropriate for assessing risk of clinical progression. [ABSTRACT FROM AUTHOR]

Individuals with spinal cord injury (SCI) report upper limb function as their top recovery priority. To accurately represent the true impact of new interventions on patient function, evaluation should occur in a natural setting. Wearable cameras can be used to monitor hand function at home, using computer vision to automatically analyze the resulting egocentric videos. A key step in this process, hand detection, is difficult to accomplish robustly and reliably, hindering the deployment of a complete monitoring system in the home and community. We propose an accurate and efficient hand detection method that uses a simple combination of existing detection and tracking algorithms, evaluated on a new hand detection dataset, consisting of 167,622 frames of egocentric videos collected from 17 individuals with SCI in a home simulation laboratory. The F1-scores for the best detector and tracker alone (SSD and Median Flow) were 0.90±0.07 and 0.42±0.18, respectively. The best combination method, in which a detector was used to initialize and reset a tracker, resulted in an F1-score of 0.87±0.07 while being two times faster than the fastest detector. The method proposed here, in combination with wearable cameras, will help clinicians directly measure hand function in a patient’s daily life at home. [ABSTRACT FROM AUTHOR]

Reference frames (or frames of reference) show how the knowledge of object organization is formed in the environment by the physical movement of the person or the environmental conditions where the representation takes place. This paper examines the formation of reference frames in memory to represent the spatial structure of large-scale outdoor environments, due to the lack of consideration in the research background, the lack of attention to the scale of the formation of reference frames, and the lack of ecological validity in other studies. For this purpose, two types of tests are used in this paper to change the scale of the environment as well as pointing targets. In one test, familiar and unfamiliar participants are introduced to the positions of the three building triads, by walking the path that encompasses each group. Then, maps are presented to them along with the representation of these three groups in five different directions (0-180 degrees), and they judge whether each triple group is correctly represented based on the relative positions of the buildings. In another test, participants are introduced to the position of eight unknown objects in a pedestrian-oriented environment, moving in two pre-programmed and inscribed paths (one path aligned with the sidewalk and the other misaligned, at a 45-degree angle). Then, participants use their memory, pointing to objects as targets. In both tests, the dependent research variables are the pointing accuracy and the latency in responding to the examiners’ questions. The results show that the positions of unfamiliar buildings are subjectively represented as egocentric reference frames. The allocentric frame of reference is defined by the environment when the environment is familiar, and the representation also tends to allocentric, as humans become familiar with the environment. On the other hand, object positions are subjectively represented in regular environments and distinctive by the geocentric frame, but are selected based on egocentric experience. [ABSTRACT FROM AUTHOR]

Episodic memory is defined as the ability to recall events in a spatiotemporal context. Formation of such memories is critically dependent on the hippocampal formation and its inputs from the entorhinal cortex. To be able to support the formation of episodic memories, entorhinal cortex and hippocampal formation should contain a neuronal code that follows several requirements. First, the code should include information about position of the agent ("where"), sequence of events ("when"), and the content of the experience itself ("what"). Second, the code should arise instantly thereby being able to support memory formation of one‐shot experiences. For successful encoding and to avoid interference between memories during recall, variations in location, time, or in content of experience should result in unique ensemble activity. Finally, the code should capture several different resolutions of experience so that the necessary details relevant for future memory‐based predictions will be stored. We review how neuronal codes in entorhinal cortex and hippocampus follow these requirements and argue that during formation of episodic memories entorhinal cortex provides hippocampus with instant information about ongoing experience. Such information originates from (a) spatially modulated neurons in medial entorhinal cortex, including grid cells, which provide a stable and universal positional metric of the environment; (b) a continuously varying signal in lateral entorhinal cortex providing a code for the temporal progression of events; and (c) entorhinal neurons coding the content of experiences exemplified by object‐coding and odor‐selective neurons. During formation of episodic memories, information from these systems are thought to be encoded as unique sequential ensemble activity in hippocampus, thereby encoding associations between the content of an event and its spatial and temporal contexts. Upon exposure to parts of the encoded stimuli, activity in these ensembles can be reinstated, leading to reactivation of the encoded activity pattern and memory recollection. [ABSTRACT FROM AUTHOR]

Economic self-interest has been central to explaining individual trade preferences. Depending on the theoretical trade model different variables influence individuals' attitude towards globalization and existing research has come to different conclusions as to whether individuals' preferences are dependent on skill level, income or the sector of employment. Other studies depart from economic self-interest by arguing that it is not self-interest that motivates individuals to form their preference, but country-level economic factors (sociotropic considerations) instead. We argue that one needs to approach trade preference formation from an information-based perspective and we test experimentally how people react if they are aware that they personally or nationally will gain or lose from trade and which of the two aspects are more important. By using survey experiments embedded in a representative national survey in the U.S. we are able to differentiate whether a person was triggered by ego- or sociotropic benefits/costs of free trade. [ABSTRACT FROM AUTHOR]

There has been significant amount of research work on human activity classification relying either on Inertial Measurement Unit (IMU) data or data from static cameras providing a third-person view. There has been relatively less work using wearable cameras, providing first-person or egocentric view, and even fewer approaches combining egocentric video with IMU data. Using only IMU data limits the variety and complexity of the activities that can be detected. For instance, the sitting activity can be detected by IMU data, but it cannot be determined whether the subject has sat on a chair or a sofa, or where the subject is. To perform fine-grained activity classification, and to distinguish between activities that cannot be differentiated by only IMU data, we present an autonomous and robust method using data from both wearable cameras and IMUs. In contrast to convolutional neural network-based approaches, we propose to employ capsule networks to obtain features from egocentric video data. Moreover, Convolutional Long Short Term Memory framework is employed both on egocentric videos and IMU data to capture the temporal aspect of actions. We also propose a genetic algorithm-based approach to autonomously and systematically set various network parameters, rather than using manual settings. Experiments have been conducted to perform 9- and 26-label activity classification, and the proposed method, using autonomously set network parameters, has provided very promising results, achieving overall accuracies of 86.6% and 77.2%, respectively. The proposed approach, combining both modalities, also provides increased accuracy compared to using only egovision data and only IMU data. [ABSTRACT FROM AUTHOR]

Indoor wayfinding poses significant challenges, as navigating complex environments can be difficult and time-consuming. Augmented reality (AR) has emerged as a promising solution to address these challenges. However, understanding how to effectively leverage AR techniques for large-scale indoor wayfinding scenarios remains unclear. In particular, the implications of AR-enabled egocentric perspectives have not been thoroughly investigated. This study aims to explore the potential benefits of AR-based egocentric perspectives and their impact on indoor wayfinding performance. A human-subject experiment (N = 31) was conducted in a multi-story building, utilizing a self-developed AR system capable of providing both traditional exocentric and innovative egocentric perspectives. The results of the experiment confirmed the performance and cognitive benefits of the AR-enabled egocentric perspective. Participants using the egocentric perspective demonstrated improved wayfinding efficiency, reduced cognitive load, and enhanced spatial awareness. These findings suggest that the AR-based egocentric perspective offers a more intuitive and effective approach to indoor wayfinding, enabling users to better process spatial information and make informed decisions during wayfinding tasks. The findings are expected to provide empirical evidence on the efficacy of AR systems for wayfinding and inspire new user interface (UI) designs that would better leverage the advantages of AR techniques. [ABSTRACT FROM AUTHOR]

Pointing to a visual target that disappears prior to movement requires the maintenance of a memory representation about the location of the target. It has been shown that a target can be stored egocentrically, allocentrically, or in both frames of reference simultaneously. The main goal of the present study was to compare the accuracy and kinematics of a pointing movement to a remembered target when egocentric, allocentric, or combined egocentric and allocentric coding was possible. The task was to localize, memorize, and reach to a remembered target. Condition 1 was the ‘no-context’ condition and involved presenting the target in a completely dark environment (egocentric condition). For 2 other conditions, the target was presented within a visual context provided by an illuminated square. Condition 2 was the ‘stationary-context’ condition and involved keeping the context at the same position during the whole trial (egocentric and/or allocentric coding). Condition 3 was a ‘moved-context’ condition that involved shifting the context to a different location during the recall delay (allocentric coding). Movement accuracy and kinematics results were strikingly similar for the moved-context and stationary-context conditions. These results suggest that when both allocentric and egocentric coding are possible, an allocentric strategy is used. [ABSTRACT FROM AUTHOR]

Spatial cognition is an umbrella term used to refer to the complex set of abilities necessary to encode, categorize, and use spatial information from the surrounding environment to move effectively and orient within it. Experimental studies indicate that the cerebellum belongs to the neural network involved in spatial cognition, although its exact role in this function remains unclear. Our aim was to investigate in a pilot study using a virtual reality navigation task in healthy subjects whether cerebellar transcranial direct current stimulation (tDCS), a non-invasive technique, influences spatial navigation. Forty healthy volunteers (24 women; age range = 20–42 years; years of education range 13–18) were recruited. The virtual reality spatial navigation task comprised two phases: encoding, in which participants actively navigated the environment and learned the spatial locations for one object, and retrieval, in which they retrieved the position of the object they had discovered and memorized in the previous encoding phase, starting from another starting point. Participants received tDCS stimulation (anodal or sham according to the experimental condition they were assigned to) for 20 min before beginning the retrieval phase. Our results showed that cerebellar tDCS left the accuracy of the three indexes used to measure effective navigational abilities unchanged. Hence, cerebellar tDCS had no influence on the retrieval phase for the spatial maps stored. Further studies, enrolling a larger sample and testing a different stimulation protocol, may give a greater insight into the role of the cerebellum in spatial navigation.