Earth-vertical motion perception assessment using an elevator: a feasibility study.

A feasible, inexpensive, rapid, and easy-to-use method to measure vestibular vertical movement perception is needed to assess the sacculus-mediated low-frequency otolith function of dizzy patients. To evaluate the feasibility of reaction time assessment in response to vertical motion induced by an elevator in healthy young individuals. We recorded linear acceleration/deceleration reaction times (LA-RT/LD-RT) of 20 healthy (13 female) subjects (mean age: 22 years ± 1 SD) as a measure of vertical vestibular motion perception. LA-RT/LD-RT were defined as the time elapsed from the start of elevator acceleration or deceleration to the time at which subjects in a sitting position indicated perceiving a change in velocity by pushing a button with their thumb. The light reaction time was measured as a reference. All 20 subjects tolerated the assessment with repeated elevator rides and reported no adverse events. Over all experiments, one upward and four downward rides had to be excluded for technical reasons (2.5%). The fraction of premature button presses varied among the four conditions, possibly related to elevator vibration (upward rides: LA-RT-up 66%, LD-RT-up 0%; downward rides: LA-RT-down 12%, LD-RT-down 4%). Thus LD-RT-up yielded the most robust results. The reaction time to earth-vertical deceleration elicited by an elevator provides a consistent indicator of linear vestibular motion perception in healthy humans. The testing procedure is inexpensive and easy to use. Deceleration on upward rides yielded the most robust measurements.

An immersive virtual reality system for ecological assessment of peripersonal and extrapersonal unilateral spatial neglect.

BACKGROUND: Unilateral spatial neglect (USN) is a debilitating neuropsychological syndrome that often follows brain injury, in particular a stroke affecting the right hemisphere. In current clinical practice, the assessment of neglect is based on old-fashioned paper-and-pencil and behavioral tasks, and sometimes relies on the examiner's subjective judgment. Therefore, there is a need for more exhaustive, objective and ecological assessments of USN. METHODS: In this paper, we present two tasks in immersive virtual reality to assess peripersonal and extrapersonal USN. The tasks are designed with several levels of difficulty to increase sensitivity of the assessment. We then validate the feasibility of both assessments in a group of healthy adult participants. RESULTS: We report data from a study with a group of neurologically unimpaired participants (N = 39). The results yield positive feedback on comfort, usability and design of the tasks. We propose new objective scores based on participant's performance captured by head gaze and hand position information, including, for instance, time of exploration, moving time towards left/right and time-to-reach, which could be used for the evaluation of the attentional spatial bias with neurological patients. Together with the number of omissions, the new proposed parameters can result in lateralized index ratios as a measure of asymmetry in space exploration. CONCLUSIONS: We presented two innovative assessments for USN based on immersive virtual reality, evaluating the far and the near space, using ecological tasks in multimodal, realistic environments. The proposed protocols and objective scores can help distinguish neurological patients with and without USN.

The cost of attentional reorienting on conscious visual perception: an MEG study.

How do attentional networks influence conscious perception? To answer this question, we used magnetoencephalography in human participants and assessed the effects of spatially nonpredictive or predictive supra-threshold peripheral cues on the conscious perception of near-threshold Gabors. Three main results emerged. (i) As compared with invalid cues, both nonpredictive and predictive valid cues increased conscious detection. Yet, only predictive cues shifted the response criterion toward a more liberal decision (i.e. willingness to report the presence of a target under conditions of greater perceptual uncertainty) and affected target contrast leading to 50% detections. (ii) Conscious perception following valid predictive cues was associated to enhanced activity in frontoparietal networks. These responses were lateralized to the left hemisphere during attentional orienting and to the right hemisphere during target processing. The involvement of frontoparietal networks occurred earlier in valid than in invalid trials, a possible neural marker of the cost of re-orienting attention. (iii) When detected targets were preceded by invalid predictive cues, and thus reorienting to the target was required, neural responses occurred in left hemisphere temporo-occipital regions during attentional orienting, and in right hemisphere anterior insular and temporo-occipital regions during target processing. These results confirm and specify the role of frontoparietal networks in modulating conscious processing and detail how invalid orienting of spatial attention disrupts conscious processing.

Spatial anxiety and self-confidence mediate sex/gender differences in mental rotation.

A recent meta-synthesis study with a sample of >12 million participants revealed that the male advantage in mental rotation (MR) is the largest cognitive sex/gender difference found in psychological literature. MR requires test takers to mentally rotate three-dimensional cubic figures under time restrictions. Previous studies have investigated how biological and social factors contribute to cognitive sex/gender differences in tasks of this type. Spatial anxiety and self-confidence in MR tasks have received less attention. The present study investigated the contribution of these psychological factors to sex/gender differences in MR performance. Participants (n = 269) completed two MR tasks that differed in task difficulty. Participants also indicated their self-confidence (for each item) and spatial anxiety. The results revealed that pronounced sex/gender differences in spatial anxiety and self-confidence mediate sex/gender in MR performance, especially when task demands are high. The current findings suggest that task-irrelevant factors that are not spatial cognitive in nature contribute largely to the well-known medium to large sex/gender differences in MR. Future studies should further explore mechanisms underlying cognitive sex/gender differences within a biopsychosocial approach.

"Run to the hills": Specific contributions of anticipated energy expenditure during active spatial learning.

Grounded views of cognition consider that space perception is shaped by the body and its potential for action. These views are substantiated by observations such as the distance-on-hill effect, described as the overestimation of visually perceived uphill distances. An interpretation of this phenomenon is that slanted distances are overestimated because of the integration of energy expenditure cues. The visual perceptual processes involved are, however, usually tackled through explicit estimation tasks in passive situations. The goal of this study was to consider instead more ecological active spatial processing. Using immersive virtual reality and an omnidirectional treadmill, we investigated the effect of anticipated implicit physical locomotion cost by comparing spatial learning for uphill and downhill routes, while maintaining actual physical cost and walking speed constant. In the first experiment, participants learnt city layouts by exploring uphill or downhill routes. They were then tested using a landmark positioning task on a map. In the second experiment, the same protocol was used with participants who wore loaded ankle weights. The results from the first experiment showed that walking uphill routes led to a global underestimation of distances compared with downhill routes. This inverted distance-of-hill effect was not observed in the second experiment, where an additional effort was applied. These results suggest that the underestimation of distances observed in Experiment 1 emerged from recalibration processes whose function was to solve the transgression of proprioceptive predictions linked with uphill energy expenditure. The results are discussed in relation to constructivist approaches on spatial representations and predictive coding theories.

Overcoming navigational challenges: A novel approach to the study and assessment of topographical orientation.

Several studies investigating environmental navigation require participants to navigate in virtual environments, in which the proprioceptive and vestibular components present during real environmental navigation are lost. Here, we aimed to provide a novel computerized ecological navigational battery, investigating whether the absence of proprioceptive and vestibular inputs yields a representation of the navigational space comparable to that acquired ecologically. In Study 1, 38 participants underwent two sets of tasks, one performed in a laboratory-based setting (LBS) and the other in an ecological environment (EE), with both including evaluation of route, landmark, and survey knowledge and a landmark ordering task. All tasks, except the route task, significantly correlated between EE and LBS. In LBS, performance in the landmark ordering task was predicted by that in the survey task, but not by those in the route and landmark tasks. Results of Study 1 were replicated in Study 2, in which 44 participants completed a modified and shorter online version of LBS tests. Reliability of the online LBS tests was also tested and showed a moderate-to-high internal consistency. Overall, results show that the conditions in which tasks are performed affect the acquisition of route knowledge, likely due to the lack of proprioceptive and vestibular information in LBS. However, LBS tasks presented here provide a standard battery of tests that can overcome the replicability problems encountered by ecological navigation tests, while taking into consideration all the complexities of navigational processes in terms of the use of landmark, route, and survey strategies.

Assessment of Color Perception and Preference with Eye-Tracking Analysis in a Dental Treatment Environment.

Nowadays, medical facilities are developing their treatment environment to provide better services to their patients. In particular, dental hospitals have been considered uncomfortable and uninviting spaces, which needs to change so that people can visit easily and feel more relaxed. However, only a few systematic studies have reported on the demand for building a comfortable space. This study aimed to investigate gaze characteristics based on a color preference survey of the dental unit chair, which has the most influence on spatial perception in the dental treatment environment, using an eye tracking technique for color. The results of this study showed that the color perception by eye tracking and the color preference by survey did not tend to match. The color most viewed by a majority of subjects was pink, which attracted a high level of attention, regardless of personal preference. In addition, for the psychological color images associated with color preference, the subjects tended to prefer images such as warmth, friendliness, and calmness. This appeared to reflect the psychology of the subjects who wished to replace their feelings of anxiety or fear when going to the dental hospital with comfort and tranquility. Therefore, colors that can provide comfort and tranquility to patients should be considered first as visual elements (e.g., brown) in creating a dental treatment environment.

The Peripersonal Space in a social world.

The PeriPersonal Space (PPS) has been defined as the space surrounding the body, where physical interactions with elements of the environment take place. As our world is social in nature, recent evidence revealed the complex modulation of social factors onto PPS representation. In light of the growing interest in the field, in this review we take a close look at the experimental approaches undertaken to assess the impact of social factors onto PPS representation. Our social world also influences the personal space (PS), a concept stemming from social psychology, defined as the space we keep between us and others to avoid discomfort. Here we analytically compare PPS and PS with the aim of understanding if and how they relate to each other. At the behavioral level, the multiplicity of experimental methodologies, whether well-established or novel, lead to somewhat divergent results and interpretations. Beyond behavior, we review physiological and neural signatures of PPS representation to discuss how interoceptive signals could contribute to PPS representation, as well as how these internal signals could shape the neural responses of PPS representation. In particular, by merging exteroceptive information from the environment and internal signals that come from the body, PPS may promote an integrated representation of the self, as distinct from the environment and the others. We put forward that integrating internal and external signals in the brain for perception of proximal environmental stimuli may also provide us with a better understanding of the processes at play during social interactions. Adopting such an integrative stance may offer novel insights about PPS representation in a social world. Finally, we discuss possible links between PPS research and social cognition, a link that may contribute to the understanding of intentions and feelings of others around us and promote appropriate social interactions.

Testosterone administration in women increases the size of their peripersonal space.

Peripersonal space (PPS) is the space immediately surrounding the body, conceptualised as a sensory-motor interface between body and environment. PPS size differs between individuals and contexts, with intrapersonal traits and states, as well as social factors having a determining role on the size of PPS. Testosterone plays an important role in regulating social-motivational behaviour and is known to enhance dominance motivation in an implicit and unconscious manner. We investigated whether the dominance-enhancing effects of testosterone reflect as changes in the representation of PPS in a within-subjects testosterone administration study in women (N = 19). Participants performed a visuo-tactile integration task in a mixed-reality setup. Results indicated that the administration of testosterone caused a significant enlargement of participants' PPS, suggesting that testosterone caused participants to implicitly appropriate a larger space as their own. These findings suggest that the dominance-enhancing effects of testosterone reflect at the level of sensory-motor processing in PPS.

Spatial orientation assessment in preschool children: Egocentric and allocentric frameworks.

Spatial orientation is an important function in daily life because it allows us to reach a target place when moving through our environment, using self-centered (egocentric) or environmental information (allocentric). Compared to other cognitive functions, spatial orientation has been studied less in preschool ages. Some brain areas, such as the hippocampus and the temporal as well as the parietal and frontal cortices, are involved in spatial orientation. Therefore, when these brain regions are altered in neurological conditions or in atypical development in children, we would expect impairment of spatial abilities. The aim of this study is to review studies, published in recent years, that use egocentric and allocentric spatial orientation tasks for assessing spatial memory in preschool children, with the final goal of finding out which tests could be included in a clinical neuropsychological evaluation. We observed that although egocentric spatial orientation emerges first during development, allocentric spatial orientation tasks are employed at very early ages. Most of these tasks are performed in real environments, allowing children's self-movements and using environmental modifications, but technologies such as virtual or augmented reality are increasingly used. Other aspects are discussed, such as the lack of consensus in the nomenclature, the difficulty of tracing the course of development of spatial orientation, or the ecological validity of the tests used. We finally observed that there is greater interest in studying the allocentric framework than the egocentric one, which makes it difficult to compare the use of the two frames of reference during a neuropsychological evaluation in preschool-aged children.

Dissociation between visuospatial neglect assessment tasks and its neuroanatomical substrates: a case report.

Visuospatial neglect possesses significant heterogeneity in clinical features and neuroanatomical substrates. Behavioral dissociations on different neglect tasks have been reported in the past, and the investigation of their respective anatomical correlates at cortical and, to a lesser degree, subcortical levels has been attempted in stroke studies. We report a patient with a neoplasm occupying the right ventral post-central gyrus and anterior supramarginal gyrus. The patient was admitted preoperatively with dissociation on the performance of neglect tasks, showing clinical deficits in the line bisection task and clock drawing, but not on the cancelation task. The patient underwent an awake craniotomy for tumor excision. Intraoperative visuospatial mapping was employed by applying direct electrical stimulation (DES) to the supramarginal gyrus and the ventral branch of the superior longitudinal fasciculus (SLF III) during the line bisection task. According to our findings, DES was ineffective at the cortical level, but it induced strong rightward bias when applied subcortically at the SLF III. By combining our preoperative and intraoperative anatomical and clinical data, we suggest that the posterior part of the SLF III might have a distinct role in the perceptual component of neglect. Our findings are discussed within the context of previous literature supporting the notion that particular behavioral features of spatial neglect are mediated by different white-matter connections.

Entorhinal-retrosplenial circuits for allocentric-egocentric transformation of boundary coding.

Spatial navigation requires landmark coding from two perspectives, relying on viewpoint-invariant and self-referenced representations. The brain encodes information within each reference frame but their interactions and functional dependency remains unclear. Here we investigate the relationship between neurons in the rat's retrosplenial cortex (RSC) and entorhinal cortex (MEC) that increase firing near boundaries of space. Border cells in RSC specifically encode walls, but not objects, and are sensitive to the animal's direction to nearby borders. These egocentric representations are generated independent of visual or whisker sensation but are affected by inputs from MEC that contains allocentric spatial cells. Pharmaco- and optogenetic inhibition of MEC led to a disruption of border coding in RSC, but not vice versa, indicating allocentric-to-egocentric transformation. Finally, RSC border cells fire prospective to the animal's next motion, unlike those in MEC, revealing the MEC-RSC pathway as an extended border coding circuit that implements coordinate transformation to guide navigation behavior.

Temporal focus and time spatialization across cultures.

The temporal focus hypothesis (TFH) proposes that whether the past or the future is conceptualized as being located in front depends on temporal focus: the balance of attention paid to the past (tradition) and the future (progress). How general is the TFH, and to what extent can cultures and subcultures be placed on a single line relating time spatialization and temporal focus in spite of stark differences in language, religion, history, and economic development? Data from 10 Western (sub)cultural groups (N = 1198,) were used to derive a linear model relating aggregated temporal focus and proportion of future-in-front responses. This model then successfully fitted 10 independently collected (sub)cultural groups in China and Vietnam (N = 899). Further analysis of the whole data set (N = 2,097) showed that the group-level relation arose at the individual level and allowed precise quantification of its influence. Finally, in an effort to apply the model to all relevant published data sets, we included recent data from Britain and South Africa: The former, but not the latter, fitted the model well. Temporal focus is a central factor that shapes how people around the world think of time in spatial terms.

Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm.

Vestibular disorders are among the most common syndromes in medicine. In recent years, new vestibular diagnostic systems have been introduced that allow the examination of all semicircular canals in the clinical setting. Assessment methods of the otolithic system, which is responsible for the perception of linear acceleration and perception of gravity, are far less in clinical use. There are several experimental approaches for measuring the perception of gravity. The most frequently used method is the determination of the subjective visual vertical. This is usually measured with the head in an upright position. We present here an assessment method for testing otolith function in the roll plane. The subjective visual vertical is measured in the head upright position as well as with head inclination of ± 15° and ± 30° in the roll plane. This extended functional paradigm is an easy-to-perform clinical test of otolith function and ensures increased information content for the detection of impaired graviceptive perception.

Piecing together the role of a spatial assembly intervention in preschoolers' spatial and mathematics learning: Influences of gesture, spatial language, and socioeconomic status.

Spatial skills are associated with mathematics skills, but it is unclear if spatial training transfers to mathematics skills for preschoolers, especially from underserved communities. The current study tested (a) whether spatial training benefited preschoolers' spatial and mathematics skills, (b) if the type of feedback provided during spatial training differentially influenced children's spatial and mathematics skills, and (c) if the spatial training's effects varied by socioeconomic status (SES). Preschoolers (N = 187) were randomly assigned to either a 'business-as-usual' control or one of three spatial training groups (modeling and feedback [MF]; gesture feedback [GF]; spatial language feedback [SLF]). Three-year-olds were trained to construct puzzles to match a model composed of various geometric shapes. New models were created similar to the 2-dimensional trials of the Test of Spatial Assembly (TOSA). Training was given once per week for 5 weeks. Preschoolers were pretested and posttested on 2D and 3D TOSA trials, spatial vocabulary, shape identification, and 2 mathematics assessments. Results indicate that first, any spatial training improved preschoolers' 2D TOSA performance, although a significant interaction with SES indicated improvement was driven by low-SES children. Furthermore, low-SES children showed greatest gains on the 2D TOSA with MF and GF. Second, MF and GF improved low-SES children's performance on the 3D TOSA. Third, only low-SES children with MF saw improvements in far-transfer to mathematics (Woodcock-Johnson: Applied Problems, but not the Test of Early Mathematical Ability). Results indicate that, especially for low-income learners, spatial training can improve children's early spatial and mathematics skills. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Cost of Dual-Task Performance in Tactile Perception Is Greater for Competing Tasks of the Same Type.

This study examines dual-task performance in the tactile modality and tests whether dual-task cost depends on task type. Experiment 1 involved competing tasks of the same type, using a primary localisation task on the left hand and a secondary localisation task on the right hand. In Experiment 2, the primary task on the left hand remained the same, while an intensity discrimination task was used as the secondary task on the right hand. Subjects in both experiments completed three conditions: the primary task alone, a dual-task condition, and the primary task with the secondary stimulus present but no response required. Across both experiments, performance on the primary task was best when it was presented alone, and there was a performance decrement when the secondary stimulus was present but not responded to. Performance on the primary task was further decreased when participants had to respond to the secondary stimulus, and the decrease was larger when the secondary task was localisation rather than discrimination. This result indicates that task type in the tactile modality may modulate the attentional cost of dual-task performance and implies partially shared resources underlie localisation and intensity discrimination.

Attentional capture by context cues, not inhibition of cue singletons, explains same location costs.

Recent attentional capture studies with the spatial cueing paradigm often found that target-dissimilar precues resulted in longer RTs on valid than invalid cue trials. These same location costs were accompanied by a contralateral positivity over posterior electrodes from 200 to 300 ms, similar to a PD component. Same location costs and the PD have been linked to the inhibition of cues with a unique feature (singleton cues) that do not match the target feature. In some studies reporting same location costs, the cue was surrounded by other cues (i.e., the context cues) that matched the physical or relative feature of the target. We hypothesized that the context cues might have captured attention and might have elicited data patterns that mimicked the inhibitory effects. To disentangle inhibition of the singleton cue from capture by the context cues, we added gray cues to the cue array, which we considered neutral because gray matched neither the target nor the nontarget color. In four experiments, the results consistently showed that the context cues in the nonmatching cue condition captured attention, as reflected in shorter RTs compared to neutral cues and a substantial N2pc to lateralized context cues. By contrast, the evidence for inhibition of the singleton cue was rather weak. Therefore, same location costs and lateralized positivity in the event-related potential of participants in several recent studies probably reflected attentional capture by the context cues, not inhibition of the singleton cue. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Prefrontal attentional saccades explore space rhythmically.

Recent studies suggest that attention samples space rhythmically through oscillatory interactions in the frontoparietal network. How these attentional fluctuations coincide with spatial exploration/displacement and exploitation/selection by a dynamic attentional spotlight under top-down control is unclear. Here, we show a direct contribution of prefrontal attention selection mechanisms to a continuous space exploration. Specifically, we provide a direct high spatio-temporal resolution prefrontal population decoding of the covert attentional spotlight. We show that it continuously explores space at a 7-12 Hz rhythm. Sensory encoding and behavioral reports are increased at a specific optimal phase w/ to this rhythm. We propose that this prefrontal neuronal rhythm reflects an alpha-clocked sampling of the visual environment in the absence of eye movements. These attentional explorations are highly flexible, how they spatially unfold depending both on within-trial and across-task contingencies. These results are discussed in the context of exploration-exploitation strategies and prefrontal top-down attentional control.

Endogenous cueing effects for detection can be accounted for by a decision model of selective attention.

Spatial cues help participants detect a visual target when it appears at the cued location. One hypothesis for this cueing effect, called selective perception, is that cueing a location enhances perceptual encoding at that location. Another hypothesis, called selective decision, is that the cue has no effect on perception, but instead provides prior information that facilitates decision-making. We distinguished these hypotheses by comparing a simultaneous display with two spatial locations to sequential displays with two temporal intervals. The simultaneous condition had a partially valid spatial cue, and the sequential condition had a partially valid temporal cue. Selective perception predicts no cueing effect for sequential displays given there is enough time to switch attention. In contrast, selective decision predicts cueing effects for sequential displays regardless of time. We used endogenous cueing of a detection-like coarse orientation discrimination task with clear displays (no external noise or postmasks). Results showed cueing effects for the sequential condition, supporting a decision account of selective attention for endogenous cueing of detection-like tasks.