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Objective: This article aimed to assess the relationship between musical training and age-related changes in binaural, temporal, and spatial processing abilities. Design: A standard group comparison study was conducted involving both musicians and nonmusicians. The effect of musical training was assessed using a battery of psychoacoustical tests (interaural time and level difference thresholds: ITD & ILD, binaural gap detection threshold, and virtual auditory space identification test) and subjective ratings (Spatial-Hearing subsection of Speech, Spatial, and Quality of Hearing scale in Kannada). Study sample: A total of 60 participants, between 41 and 70 years, were divided into three groups of 20 each, based on their age (41–50, 51–60, and 61–70 years). Each of these three groups was subdivided into two, one comprising 10 musicians (vocalists practicing South-Indian classical music) and the other comprising 10 nonmusicians. Results: Multivariate analyses of variance revealed that musicians performed significantly better ( p < .001) than nonmusicians in all the tests. Analyses of variance showed that whereas age had no effect ( p > .05) on performance in any of the tests in musicians, age affected the performance of nonmusicians significantly in terms of ITD ( p = .02) and ILD ( p = .01) thresholds. Conclusion: Musical training appears to have the potential to slow down age-related decline in binaural, temporal, and spatial processing.

Functional Near Infrared Spectroscopy (fNIRS) may be a suitable, simple, and cost-effective brain imaging technique for detecting divergent neuronal patterns at an early stage of neurodegeneration. In course of Mild Cognitive Impairment (MCI) or Alzheimer's disease (AD), a deficit in visual-spatial processing, located in the parietal cortex, is a reliable risk factor. Earlier, we established the application of the clock-hand-angle-discrimination task (ADT) during fNIRS to identify neuronal correlates of the visual-spatial processing in a healthy elderly sample. In this analysis, we aimed to measure and find out differences in the hemodynamic response in MCI participants compared to matched healthy controls. As expected, MCI participants showed more errors over all conditions of pointer length and a higher reaction time in the long and middle pointer length condition. Moreover, results revealed a significant reduction of cortical activation in MCI patients. There was a generally increased activity in both the right as compared to the left hemisphere and the superior parietal brain region as compared to the inferior parietal brain region in both groups. In summary, fNIRS can be implemented in the measurement of visual-spatial processing in MCI patients and healthy elderly based on ADT. MCI participants had difficulties to cope with the ADT. Since neuronal hypoactivity occurs with concomitant behavioral deficits, an additional analysis was performed on a subgroup of MCI patients who performed as well as the control group in behavior. This subgroup analysis also showed a hypoactivation of the parietal cortex, without evidence of a compensatory activation. Therefore, we assume that MCI patients are characterized by a deficit in the parietal cortex. Overall, these findings confirm our hypothesis that hemodynamic deficits in visual-spatial processing, localized in the parietal cortex, are reliable and early diagnostic markers for cognitive decline in risk groups for the development of AD.

Contains fulltext : 278678.pdf (Publisher’s version ) (Open Access) The sense of touch is not restricted to the body but can also extend to external objects. When we use a handheld tool to contact an object, we feel the touch on the tool and not in the hand holding the tool. The ability to perceive touch on a tool actually extends along its entire surface, allowing the user to accurately localize where it is touched similarly as they would on their body. Although the neural mechanisms underlying the ability to localize touch on the body have been largely investigated, those allowing to localize touch on a tool are still unknown. We aimed to fill this gap by recording the electroencephalography signal of participants while they localized tactile stimuli on a handheld rod. We focused on oscillatory activity in the alpha (7-14 Hz) and beta (15-30 Hz) ranges, as they have been previously linked to distinct spatial codes used to localize touch on the body. Beta activity reflects the mapping of touch in skin-based coordinates, whereas alpha activity reflects the mapping of touch in external space. We found that alpha activity was solely modulated by the location of tactile stimuli applied on a handheld rod. Source reconstruction suggested that this alpha power modulation was localized in a network of fronto-parietal regions previously implicated in higher-order tactile and spatial processing. These findings are the first to implicate alpha oscillations in tool-extended sensing and suggest an important role for processing touch in external space when localizing touch on a tool. 12 p.

People can support abstract reasoning by using mental models with spatial simulations. Such models are employed when people represent elements in terms of ordered dimensions (e.g. who is oldest, Tom, Dick, or Harry). We test and find that the process of forming and using such mental models can influence the liking of its elements (e.g. Tom, Dick, or Harry). The presumed internal structure of such models (linear-transitive array of elements), generates variations in processing ease (fluency) when using the model in working memory (see the Symbolic Distance Effect, SDE). Specifically, processing of pairs where elements have larger distances along the order should be easier compared to pairs with smaller distances. Elements from easier pairs should be liked more than elements from difficult pairs (fluency being hedonically positive). Experiment 1 shows that unfamiliar ideographs are liked more when at wider distances and therefore easier to process. Experiment 2 replicates this effect with non-words. Experiment 3 rules out a non-spatial explanation of the effect while Experiments 4 offers a high-powered replication. Experiment 5 shows that the spatial effect spontaneously emerges after learning, even without a task that explicitly focuses on fluency. Experiment 6 employed a shorter array, but yielded no significant results.

Objective The purpose of this study was to determine better- ear listening effect on spatial separation with the N1–P2 complex. Methods Twenty individuals with normal hearing participated in this study. The speech stimulus /ba/ was presented in front of the participant (0°). Continuous Speech Noise (5 dB signal-to-noise ratio) was presented either in front of the participant (0°), left-side (-90°), or right-side (+90°). N1- P2 complex has been recorded in quiet and three noisy conditions. Results There was a remarkable effect of noise direction on N1, P2 latencies. When the noise was separated from the stimulus, N1 and P2 latency increased in terms of when noise was co-located with the stimulus. There was no statistically significant difference in N1-P2 amplitudes between the stimulus-only and co-located condition. N1-P2 amplitude was increased when the noise came from the sides, according to the stimulus-only and co-located conditions. Conclusion These findings demonstrate that the latency shifts on N1-P2 complex explain cortical mechanisms of spatial separation in better-ear listening.

La ville de Tindouf est caractérisée par la fréquence des zones inondables qui affectent dangereusement de nombreux quartiers à forte densité de population. Ces sites affectés par d’importantes crues lors d’orages et affichent une grande vulnérabilité pour une population de 75 000 habitants, mais aussi pas moins de 15 000 constructions menacées de ruines : par l’ampleur des dommages spectaculaires aux constructions. La ville de Tindouf offre toutes les conditions de potentiel élevé de dégradation de l’habitat en Algérie. Les inondations ont pour origine des événements météorologiques et/ou hydrologiques de nature stochastique, sont très difficiles à prévoir quant à leur période de retour et à leur intensité. Une démarche méthodologique sur les anciennes agglomérations regroupant les quartiers [Remadine – Moussani - Guessabi] permettant ainsi de délimiter les zones vulnérables et de proposer des aménagements urbains pour leurs protections. Les résultats obtenus montrent la distribution spatiale de la vulnérabilité des quartiers historiques et proposent une approche de conservation pour le développement durable. The city of Tindouf is characterized by the frequency of flood zones which dangerously affect many densely populated neighbourhoods. These sites affected by major floods during thunderstorms and display great vulnerability for a population of 75,000 inhabitants, but also no less than 15,000 constructions threatened with ruins: by the extent of the spectacular damage to constructions. The city of Tindouf offers all the conditions of high potential for habitat degradation in Algeria. Floods originate from meteorological and/or hydrological events of a stochastic nature are very difficult to predict as to their return period and their intensity. A methodological approach on the old agglomerations grouping the districts [Remadine - Moussani - Guessabi] thus making it possible to delimit the vulnerable zones and to propose urban developments for their protections. The results obtained show the spatial distribution of the vulnerability of historic districts and propose a conservation approach for sustainable development.

Could learning that uses cognitive control to judiciously use relevant information while ignoring distractions generally improve brain function, beyond forming explicit memories? According to a neuroplasticity hypothesis for how some cognitive behavioural therapies are effective, cognitive control training (CCT) changes neural circuit information processing1–3. Here we investigated whether CCT persistently alters hippocampal neural circuit function. We show that mice learned and remembered a conditioned place avoidance during CCT that required ignoring irrelevant locations of shock. CCT facilitated learning new tasks in novel environments for several weeks, relative to unconditioned controls and control mice that avoided the same place during reduced distraction. CCT rapidly changes entorhinal cortex-to-dentate gyrus synaptic circuit function, resulting in an excitatory–inhibitory subcircuit change that persists for months. CCT increases inhibition that attenuates the dentate response to medial entorhinal cortical input, and through disinhibition, potentiates the response to strong inputs, pointing to overall signal-to-noise enhancement. These neurobiological findings support the neuroplasticity hypothesis that, as well as storing item–event associations, CCT persistently optimizes neural circuit information processing. Studies in mice show that cognitive control training rapidly improves brain circuit function and enhances subsequent learning, which both persist for months.

Vision and touch both support spatial information processing. These sensory systems also exhibit highly specific interactions in spatial perception, which may reflect multisensory representations that are learned through visuo-tactile (VT) experiences. Recently, Wani and colleagues reported that task-irrelevant visual cues bias tactile perception, in a brightness-dependent manner, on a task requiring participants to detect unimanual and bimanual cues. Importantly, tactile performance remained spatially biased after VT exposure, even when no visual cues were presented. These effects on bimanual touch conceivably reflect cross-modal learning, but the neural substrates that are changed by VT experience are unclear. We previously described a neural network capable of simulating VT spatial interactions. Here, we exploited this model to test different hypotheses regarding potential network-level changes that may underlie the VT learning effects. Simulation results indicated that VT learning effects are inconsistent with plasticity restricted to unisensory visual and tactile hand representations. Similarly, VT learning effects were also inconsistent with changes restricted to the strength of inter-hemispheric inhibitory interactions. Instead, we found that both the hand representations and the inter-hemispheric inhibitory interactions need to be plastic to fully recapitulate VT learning effects. Our results imply that crossmodal learning of bimanual spatial perception involves multiple changes distributed over a VT processing cortical network.

Even though vision is considered the best suited sensory modality to acquire spatial information, blind individuals can form spatial representations to navigate and orient themselves efficiently in space. Consequently, many studies support theamodality hypothesisof spatial representations since sensory modalities other than vision contribute to the formation of spatial representations, independently of visual experience and imagery. However, given the high variability in abilities and deficits observed in blind populations, a clear consensus about the neural representations of space has yet to be established. To this end, we performed a meta-analysis of the literature on the neural correlates of spatial processing and navigation via sensory modalities other than vision, like touch and audition, in individuals with early and late onset blindness. An activation likelihood estimation (ALE) analysis of the neuroimaging literature revealed that early blind individuals and sighted controls activate the same neural networks in the processing of non-visual spatial information and navigation, including the posterior parietal cortex, frontal eye fields, insula, and the hippocampal complex. Furthermore, blind individuals also recruit primary and associative occipital areas involved in visuo-spatial processing via cross-modal plasticity mechanisms. The scarcity of studies involving late blind individuals did not allow us to establish a clear consensus about the neural substrates of spatial representations in this specific population. In conclusion, the results of our analysis on neuroimaging studies involving early blind individuals support theamodality hypothesisof spatial representations.

Our experience of the world seems to unfold seamlessly in a unitary 3D space. For this to be possible, the brain has to merge many disparate cognitive representations and sensory inputs. How does it do so? I discuss work on two key combination problems: coordinating multiple frames of reference (e.g. egocentric and allocentric), and coordinating multiple sensory signals (e.g. visual and proprioceptive). I focus on two populations whose spatial processing we can observe at a crucial stage of being configured and optimised: children, whose spatial abilities are still developing significantly, and naïve adults learning new spatial skills, such as sensing distance using auditory cues. The work uses a model-based approach to compare participants’ behaviour with the predictions of alternative information processing models. This lets us see when and how—during development, and with experience—the perceptual-cognitive computations underpinning our experiences in space change. I discuss progress on understanding the limits of effective spatial computation for perception and action, and how lessons from the developing spatial cognitive system can inform approaches to augmenting human abilities with new sensory signals provided by technology.

Legal systems often rule that people own objects in their territory. We propose that an early-developing ability to make territory-based inferences of ownership helps children address informational demands presented by ownership. Across 6 experiments (N = 504), we show that these inferences develop between ages 3 and 5 and stem from two aspects of the psychology of ownership. First, we find that a basic ability to infer that people own objects in their territory is already present at age 3 (Experiment 1). Children even make these inferences when the territory owner unintentionally acquired the objects and was unaware of them (Experiments 2 and 3). Second, we find that between ages 3 and 5, children come to consider past events in these judgments. They move from solely considering the current location of an object in territory-based inferences, to also considering and possibly inferring where it originated (Experiments 4 to 6). Together, these findings suggest that territory-based inferences of ownership are unlikely to be constructions of the law. Instead, they may reflect basic intuitions about ownership that operate from early in development.

Full dataset and supplementary analyses for Lopiccolo and Chang (2021, "Cultural factors weaken but do not reverse left-to-right spatial biases in numerosity processing: Data from Arabic and English monoliterates and Arabic-English biliterates", PLoS ONE). The dataset is provided in Excel format (.xlsx) and tab-delimited text format (.txt): Sheet 1 of the Excel file provides the raw (trial-by-trial) reaction time data; Sheet 2, the reaction time difference data; Sheet 3, the demographic data for all participants; and Sheet 4, a key explaining each column of the data spreadsheets in sheets 1-3. Supplementary analyses of error rates, along with a summary table of raw response times, are provided in the PDF file.

Test materials for Lopiccolo and Chang (2021, "Cultural factors weaken but do not reverse left-to-right spatial biases in numerosity processing: Data from Arabic and English monoliterates and Arabic-English biliterates", PLoS ONE), which are shareable publicly according to the study's IRB protocol: (1) language background & handedness questionnaire in Arabic, (2) language background & handedness questionnaire in English, and (3) MATLAB script for generating numerosity image files (from Gebuis & Reynvoet, 2011).

As mentioned in the project preregistration, we would like to explore whether spatial processing during a seemingly automatic multisensory integration phenomenon like the sound-induced flash illusion, can be modulated by attentional load. In Experiment 1, it will be used a dual-task that combines a primary audiovisual integration task with stimuli eliciting the sound-induced-flash illusion presented on the left or on the right side of the screen and a concurrent secondary working memory task to manipulate levels of attentional load in younger adults. Specifically, in the encoding phase of the working memory task, participants will have to memorize short or long sequences (low/high load) of consonants or spatial positions (verbal/spatial load). Thereafter, in the audiovisual integration task, they will be presented simultaneously with one or two lateralized flashes and binaural sounds and will have to report the number of perceived flashes. Usually, accuracy in reporting the number of perceived flashes is higher when the number of flashes and sounds is congruent (1F1S and 2F2S trials), while it drops when it is incongruent, as sounds influence flashes perception in an illusory way (1F2S and 2F1S trials); specifically, 1F2S trials can lead to split the visual percept and to report two flashes (i.e., fission illusion), while 2F1S trials can induce to merge the visual percepts and to report one flash (i.e., fusion illusion) (Andersen et al., 2004; Shams et al., 2000, 2002). Finally, in the test phase of the working memory task, participants will have to report the sequences of previously encoded stimuli. This procedure allows to vary load offline, indeed the working memory stimuli used to manipulate load will be presented before audiovisual integration stimuli. A peculiarity of the experiment is that participants recruitment and data collection will take place entirely via web.

Many attention theories assume that selection is guided by a preattentive, spatial representation of the scene that combines bottom-up stimulus information with top-down influences (task goals and prior experience) to code for potentially relevant locations (priority map). At which level(s) of priority computation top-down influences modulate bottom-up stimulus signals is an open question. In a visual-search task, here we induced experience-driven spatial suppression (statistical learning) by presenting 1 of 2 salient distractors more frequently in one display region than the other. When a distractor standing out in the same dimension as the target was spatially biased in Experiment 1, processing of both the target and another, spatially unbiased distractor standing out in a different dimension was likewise hampered in the suppressed region. This indicates that constraining spatial suppression to a specific distractor feature is not possible, and participants instead resort to purely space-based (distractor-feature-independent) suppression at a supradimensional, overall-priority map. In line with a common locus of suppression, a novel computational model of distraction in visual search captures all 3 location effects with a single spatial-weighting parameter. In contrast, when the different-dimension distractor was spatially biased in Experiment 2, processing of other objects in the suppressed region was unaffected, indicating suppression constrained to a subordinate, dimension-specific level of priority computation. In sum, we demonstrate experience-driven top-down modulations of saliency signals at the overall-priority and dimension-specific levels that do not reach down to the specific distractor features. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Objectives: Hamstring injuries in athletes can lead to significant time away from competition as a result of persistent posterior thigh pain. These cases are often difficult to treat as the state of the tissues alone cannot explain symptoms. In non-athletic populations with persistent pain, disruptions to tactile, proprioceptive, and spatial cortical representations exist, which has led to promising brain-based treatments.Here, we explored whether athletes with persistent posterior thigh pain also display impairments in these cortical representations.Design: Cross-sectional study.Methods: Fourteen male professional athletes with persistent posterior thigh pain (‘Patients’) and 14pain-free age, sport, body mass index and level-matched controls (‘Controls’) participated. The tactile cortical representation was assessed using two-point discrimination (TPD) threshold and accuracy of tactile localisation; the proprioceptive cortical representation was assessed using a left/right judgement task; spatial processing was assessed using an auditory detection task. Results: TPD thresholds were similar for Patients and Controls (p = 0.70). Patients were less accurate at localising tactile stimuli delivered to their affected leg, slower to make left/right judgements when the lower limb image corresponded to the side of their affected leg, and less accurate at detecting auditory stimuli delivered near their affected leg, when compared to their healthy leg or to the leg of Controls(p < 0.01 for all). Conclusions: Leg-specific tactile, proprioceptive, and spatial processing deficits exist in athletes with persistent posterior thigh pain. That these processing deficits exist despite rehabilitation and normal tissue healing time suggests they may play a role in the persistence of posterior thigh pain. Refereed/Peer-reviewed

Healthy individuals display systematic inaccuracies when allocating attention to perceptual space. Under many conditions, optimized spatial attention processing of the right hemisphere’s frontoparietal attention network directs more attention to the left side of perceptual space than the right. This is the pseudoneglect effect. We present evidence reshaping our fundamental understanding of this neural mechanism. We describe a previously unrecognized, but reliable, attention bias to the right side of perceptual space that is associated with semantic object processing. Using an object bisection task, we revealed a significant rightward bias distinct from the leftward bias elicited by the traditional line bisection task. In Experiment 2, object-like shapes that were not easily recognizable exhibited an attention bias between that of horizontal lines and objects. Our results support our proposal that the rightward attention bias is a product of semantic processing and its lateralization in the left hemisphere. In Experiment 3, our novel object-based adaptation of the landmark task further supported this proposition and revealed temporal dynamics of the effect. This research provides novel and crucial insight into the systems supporting intricate and complex attention allocation and provides impetus for a shift toward studying attention in ways that increasingly reflect our complex environments., Public Significance Statement This study describes a previously unrecognized but reliable spatial attention bias that is associated with the processing of the semantic meaning of objects. This counters the spatial attention bias well-known as the pseudoneglect effect. Our findings implicate a crucial role for the understudied left frontoparietal cortex in distributing attention, and open new, exciting areas for research. This work also reveals a mechanism that potentially enables our attention to be directed equally to different areas of space in daily life.

A major goal of many translational neuroimaging studies is the identification of biomarkers of disease. However, a prerequisite for any such biomarker is robust reliability, which for magnetoencephalography (MEG) and many other imaging modalities has not been established. In this study, we examined the reliability of visual (Experiment 1) and somatosensory gating (Experiment 2) responses in 19 healthy adults who repeated these experiments for three visits spaced 18 months apart. Visual oscillatory and somatosensory oscillatory and evoked responses were imaged, and intraclass correlation coefficients (ICC) were computed to examine the long-term reliability of these responses. In Experiment 1, ICCs showed good reliability for visual theta and alpha responses in occipital cortices, but poor reliability for gamma responses. In Experiment 2, the time series of somatosensory gamma and evoked responses in the contralateral somatosensory cortex showed good reliability. Finally, analyses of spontaneous baseline activity indicated excellent reliability for occipital alpha, moderate reliability for occipital theta, and poor reliability for visual/somatosensory gamma activity. Overall, MEG responses to visual and somatosensory stimuli show a high degree of reliability across 3 years and therefore may be stable indicators of sensory processing long term and thereby of potential interest as biomarkers of disease.

Humans have the subjective impression of a rich perceptual experience, but this perception is riddled with errors that might be produced by top-down expectancies or failures in feature integration. The role of attention in feature integration is still unclear. Some studies support the importance of attention in feature integration, whereas others suggest that feature integration does not require attention. Understanding attention as a heterogeneous system, in this study, we explored the role of divided (as opposed to focused—Experiment 1) attention, and endogenous–exogenous spatial orienting (Experiments 2 and 3) in feature integration. We also explored the role of feature expectancy, by presenting stimulus features that were completely unexpected to the participants. Results demonstrated that both endogenous and exogenous orienting improved feature integration whereas divided attention did not. Moreover, a strong and consistent feature expectancy effect was observed, demonstrating perceptual completion when an unexpected perceptual feature was presented in the scene. These results support the feature confirmation account, which proposes that attention is important for top-down matching of stable representations.

SIGNIFICANCE This study suggests that Chinese newspaper characters are more legible than English newspaper letters. Characters in Chinese newspapers have higher acuity reserve than English newspapers. PURPOSE The purpose of this study was to evaluate visual demand and acuity reserve for Chinese newspapers in comparison with published data on U.S. newspapers. METHODS The test distances for visual acuity in Chinese clinical studies were reviewed systematically. Characters from different sections of newspapers printed in simplified Chinese were evaluated. The character height, frequency, and visual demand and acuity reserve of each newspaper section were determined for Chinese characters of the six different levels of complexity. RESULTS More than 70% of Chinese clinical studies measure near visual acuity at either 33 or 40 cm. The height of Chinese characters ranged from 1.95 to 3.28 mm across different sections of five newspapers compared with 1.0 to 2.0 mm for English letters. The frequency of Chinese characters from least to most complex ranged from 7 to 34% across 12 sections of one Chinese newspaper. The angular threshold across the six complexity levels of Chinese characters ranged from 4.62 to 5.93 arcmin (0.54 to 0.69 mm at 40-cm reading distance) with a weighted angular threshold of 5.18 arcmin compared with 3.37 arcmin (0.39 mm) for the English letters. For Chinese newspapers, at 40-cm reading distance, the acuity reserve for the smallest and largest median size was 3.55 and 4.61, respectively. CONCLUSIONS Chinese characters are larger than English characters in all newspaper sections newspapers by a factor of 1.60 to 2.34. Given that Chinese characters need to be 1.54 times larger than English letters to provide the same acuity reserve, on average, Chinese newspapers are more legible than U.S. English newspapers.

Objectives Latinos are 1.5 times as likely to develop Alzheimer’s dementia as non-Latino Whites. This health disparity may arise from multiple influences with culturally relevant factors receiving increasing attention. Models of acculturation stress the importance of considering acculturation-related factors within the context of socioenvironmental factors to better capture the Latino experience in the United States. Methods We measured 10 acculturation and contextually-related variables in 199 Latinos (age 69.7 years) without dementia participating in Rush Alzheimer’s Disease Center studies. We tested the relationship between these variables via Principal Component Analysis (PCA), then investigated how resulting components associated with level of and longitudinal change in global and domain-specific cognition using separate linear mixed-effects models adjusted for relevant confounders and their interactions with time. Results The PCA revealed a 3-factor unrotated solution (variance explained ~70%). Factor 1, representing acculturation-related aspects of nativity, language- and social-based acculturation, was positively associated with level, but not change, in global cognition, semantic memory, and perceptual speed. Factor 2, representing contextually-related socioenvironmental experiences of discrimination, social isolation, and social networks, was negatively associated with level of global cognition, episodic and working memory, and faster longitudinal decline in visuospatial ability. Factor 3 (familism only) did not associate with level or change in any cognitive outcome. Discussion Acculturation- and contextually-related factors differentiated from each other and differentially contributed to cognition and cognitive decline in older Latinos. Providers should query acculturation and lived experiences when evaluating cognition in older Latinos.

BackgroundA mutation in C9orf72 constitute a cross-link between amyotrophic lateral sclerosis (ALS) and fronto-temporal dementia (FTD). At clinical manifestation, both patient groups may present with either cognitive impairment of predominantly behaviour or language (in FTD) or motor dysfunctions (in ALS).MethodsIn total, 36 non-symptomatic mutation carriers from ALS or FTD families were examined, including 21 subjects with C9orf72 and 15 with SOD1 mutations. Data were compared with 91 age-matched, education-matched and gender-matched healthy subjects (56 were first-degree relatives from ALS or FTD families, 35 with no known family history of ALS/FTD). MRI scanning for diffusion tensor imaging was performed to map fractional anisotropy (FA). Subjects performed an extensive neuropsychological assessment to address verbal fluency, language, executive, memory and visuospatial function. Measurements were repeated after 12 months.ResultsC9orf72 expansion carriers performed significantly worse in verbal fluency and non-verbal memory and presented with distinct alterations in structural white matter integrity indicated by lower FA values in inferior and orbitofrontal cortical areas compared with carriers of SOD1 mutations or healthy subjects. Loss of structural integrity was associated with decreased verbal fluency performance. White matter alterations and cognitive performance showed no changes over 12 months in all subjects.DiscussionReduced verbal fluency performance seems to be a distinct clinical feature of C9orf72 carriers before symptomatic disease onset without evidence for change over time in our cohort. The results support the emerging hypothesis of a general disorder in development in addition to neurodegeneration in C9orf72 carriers.

The hydrogeological environment of the Saharan North East region of Tindouf is of utmost interest, particularly in agriculture. In fact, exploitation and exploration processes must be analysed to ensure sufficient water production. This study demonstrates the value of spatial processing and exploitation of geoelectric and geological data in the study area and facilitates interpretation. The results of the electrical survey and the spatial analysis of the data allowed us to design a complete model that met the needs of hydrogeology. The applied methodology consists in breaking down our subject into three (3) classes of entities: geomatics, geophysics and hydrogeology. Synthetic mapping based on continuity is the result of studying two sites (Hassi Naga and Hassi Khebi) for geological analysis. Knowing that the electrical resistivity is between 0 and 3000 Ohm-meter, we were able to construct thematic maps showing the spatial distribution of the facies and the probable positions of the boreholes. The study provided with a geo-spatial model highlighting the impact of measurements in hydrogeology of the area considered that was called SIHE (Information System for Environmental Hydrogeology).

Objectives Visuospatial neglect (VSN) is a common cognitive disorder after stroke. The primary aim of this systematic review was to provide an overview of the impact of VSN in 3 aspects: (1) activities of daily living (ADL), (2) participation, and (3) caregiver burden. The second aim was to investigate the differences in studies focusing on populations with mean age Methods PubMed, EMBASE, Web of Science, Cochrane Library, Emcare, PsychINFO, Academic Search Premier and CENTRAL were searched systematically. Quality was assessed with the Mixed Methods Appraisal Tool. Results Of the 115 included studies, 104 provided outcomes on ADL, 15 on participation (4 studies with mean age ≥ 65), and 2 on caregiver burden (1 study with mean age ≥ 65). Quality assessment yielded scores ranging from 0 to 100%. VSN had a negative impact on ADL (i.e., independence during ADL and performance in self-care, household tasks, reading, writing, walking, wheelchair navigation) and participation (i.e., driving, community mobility, orientation, work). The impact of VSN on fulfilling social roles was unclear. VSN had a negative effect on caregiver burden. We found no clear age-related differences. Conclusions and implications VSN has a negative impact not only on patients’ independence but particularly on the performance of ADL. Despite the far fewer studies of VSN as compared with ADL, VSN also seems to hamper participation and increase caregiver burden, but further research is needed. Because of the large impact, VSN should be systematically and carefully assessed during rehabilitation. A considerable number of different instruments were used to diagnose VSN. Diagnosing VSN at more than one level [function (i.e., pen-and-paper test), activities, and participation] is strongly recommended. Consensus is needed on how to assess VSN and its negative impact for research and rehabilitation practice. Systematic review Registration No. PROSPERPO Registration No. CRD42018087483.

The present study investigated how response mode determines the specificity of control responsible for the congruency sequence effect (CSE), especially when conflict arises from spatial dimensions. Horizontal and vertical Simon tasks were presented in turn, while response mode (Experiment 1) or task-relevant stimulus dimension (Experiment 2) was manipulated. All responses were made by aimed movements to make the relative salience of the horizontal and vertical dimensions equivalent regardless of response mode. The confound-minimized CSEs were significant only when the two tasks shared the same response mode, which did not vary as a function of task-relevant stimulus dimension. This result suggests that response mode determines the scope of control, as it reconfigures the representations of the task-irrelevant spatial dimensions (i.e., the horizontal and vertical dimensions), which is corroborated by distributional analyses. This response mode-specific control was also consistently found for the horizontal and vertical arrow versions of flanker-compatibility tasks in Experiment 3, in which conflict does not directly arise from the response dimension. Furthermore, the current findings revealed that the CSEs were more evident in movement times than in initiation times, which provides new insight on how control inhibits the response activated by a task-irrelevant stimulus dimension, especially at a motor level.

Recent studies showed that some adults with dyslexia have difficulty processing sequentially arranged information. In a companion study, this deficit manifested as low accuracy during a word pair comparison task involving same/different decisions when two words differed in their letter sequences. This sequential deficit was associated with left/right spatial letter confusion. In the present study, we found the same underlying difficulty with sequential and spatial letter processing during word spelling. Participants were the same 22 adults with dyslexia and 20 age- and gender-matched controls as in the companion study. In the spelling task, sequential error rates were higher in the dyslexia group, compared to the controls. Measures of accuracy of serial letter order during the spelling task and the word comparison task were correlated. Only three participants, each with dyslexia, produced left/right letter reversals during spelling. These were the same participants who produced left/right errors when naming single letters. They also had profound difficulty with sequential and left/right letter processing in the spelling and word comparison tasks, and they had the most severe spelling impairment. We conclude that this pervasive, persistent difficulty with sequential and spatial reversals contributes to a severe dyslexia subtype. In the dyslexia group as a whole, additional and separate sources of errors were underspecified word representations in long-term memory and homophone errors that likely represent language-based deficits in word knowledge. In the participants, these three factors (sequential/spatial letter confusion, underspecified word form representation, language-based deficits) occurred either as single factors or in combination with each other.

OBJECTIVE To detail the characteristic traits of children with fetal alcohol spectrum disorders (FASDs) and maternal risk factors in a southeastern U.S. County. METHODS Independent samples were drawn from 2 different cohorts of first-grade students. All consented children (49.8%) were measured for height, weight, and head circumference, and those ≤ 25th centile entered the study along with a random sample drawn from all enrolled students. Study children were examined for physical growth, dysmorphology, and neurobehavior, and their mothers were interviewed. RESULTS Total dysmorphology scores discriminated well the physical traits of children across the FASD continuum: fetal alcohol syndrome (FAS) = 15.8, partial FAS (PFAS) = 10.8, alcohol-related neurobehavioral disorder (ARND) = 5.2, and typically developing controls = 4.4. Additionally, a neurobehavioral battery distinguished children with each FASD diagnosis from controls. Behavioral problems qualified more children for FASD diagnoses than cognitive traits. Significant proximal maternal risk variables were as follows: reports of prepregnancy drinking, drinking in any trimester, and comorbid use of other drugs in lifetime and during pregnancy, especially alcohol and marijuana (14.9% among mothers of children with FASD vs. 0.4% for controls). Distal maternal risks included reports of other health problems (e.g., depression), living unmarried with a partner during pregnancy, and a lower level of spirituality. Controlling for other drug use during pregnancy, having a child diagnosed with a FASD was 17.5 times greater for women who reported usual consumption of 3 drinks per drinking day prior to pregnancy than for nondrinking mothers (p

This study recruited kindergarteners and first graders to investigate gender and grade differences in semantic and spatial processing of number magnitude. Results based on the Bayesian statistics showed that (1) there was extreme evidence in favour of grade differences in both semantic processing and spatial processing; (2) there were no gender differences in semantic processing; and (3) boys developed earlier than girls in spatial processing of numbers, especially for the more difficult task. These results are discussed in terms of gender differences in cognitive mechanisms underlying semantic and spatial processing of number magnitude.

The capacity-limited human brain is constantly confronted with a huge amount of sensory information. Selective attention is needed for biasing neural processing towards relevant information and consequently allows meaningful interaction with the environment. Activity in the alpha-band has been proposed to be related to top-down modulation of neural inhibition and could thus represent a viable candidate to control the priority of stimulus processing. It is, however, unknown whether modulations in the alpha-band directly relate to changes in the sensory gain control of the early visual cortex. Here, we used a spatial cueing paradigm while simultaneously measuring ongoing alpha-band oscillations and steady-state visual evoked potentials (SSVEPs) as a marker of continuous early sensory processing in the human visual cortex. Thereby, the effects of spatial attention for both of these signals and their potential interactions were assessed. As expected, spatial attention modulated both alpha-band and SSVEP responses. However, their modulations were independent of each other and the corresponding activity profiles differed across task demands. Thus, our results challenge the view that modulations of alpha-band activity represent a mechanism that directly alters or controls sensory gain. The potential role of alpha-band oscillations beyond sensory processing will be discussed in light of the present results.

Introduction: Persons with Alzheimer’s disease (AD) have profound impairment in wayfinding, potentially related to a deficit in visual attention and selection of relevant environmental information. This study sought to determine differences in visual attention to salient visual cues and nonsalient cues (building features) in older adults with and without AD during active wayfinding in a large-scale, virtual reality spatial task. Methods: Fifteen subjects (7 with AD and 8 controls without AD) were asked to find their way repeatedly during 10 trials in a virtual simulation of a senior retirement community. Subjects wore eye tracking glasses to capture visual fixations while wayfinding. The least square means (LSMs) and their standard errors (SEs) for percentage of fixations and duration of fixations on salient and nonsalient cues were estimated from the linear mixed effects models and compared by group (AD or control) and cue type. Results: The group by cue type interaction was significant for both percentage of fixations (F(1, 13) = 6.79, p = 0.02) and duration of fixations (F(1, 13) = 4.87, p = 0.04). The AD group had significantly lower percentages of fixations on salient cues, LSM = 57.91 (SE = 2.44), compared to controls, LSM = 66.40 (SE = 2.19); p = 0.03. Persons with AD had a higher percentage of fixations on building features, LSM = 31.65 (SE = 2.18), than controls, LSM = 24.54 (SE = 1.95); p = 0.02. Shorter durations of fixations on salient cues were experienced by the AD group, LSM = 38.89 (SE = 1.69), than the control group, LSM = 44.69 (SE = 1.55); p = 0.02. Discussion/Conclusion: Individuals with AD may have difficulty selecting relevant information for wayfinding as compared to normally aging individuals and attend more frequently than controls to irrelevant information. This may help explain the wayfinding difficulties seen in AD.

A dual task was designed to involve a tracking mission with various tracking speeds and a spatial compatibility task with various signal-key mappings and presentation modalities. This dual task was used to investigate the effects of workload and resource competition in distinct parts of the dual-task process. The results demonstrated that increasing the tracking speed adversely affected the tracking performance but led to positive arousal to the secondary discrete response task. Visual spatial signals gave the shortest reaction time due to the optimal time-sharing of the visual resources in the focal and ambient channels. Compared with visual spatial signals, spatial signals of auditory and tactile modalities did not lead to an improved performance because of their cross-modality nature. These findings provided practical design guidelines for dual tasks in which the operators need to complete a continuous monitoring task visually and elicit timely and accurate responses to spatial information.

Humans have associations between numbers and physical space on both horizontal and vertical dimensions, called Spatial-Numerical Associations (SNAs). Several studies have considered the hypothesis of there being a dominant orientation by examining on which dimension people are more accurate and efficient at responding during various directional SNA tasks. However, these studies have difficulty differentiating between a person’s efficiency at accessing mental representations of numbers in space, and the efficiency at which they exercise motor control functions, particularly bilateral ones, when manifesting a response during an explicit directional SNA task. In this study we use a conflict test employing combined explicit magnitude and spatial directional processing in which pairs of numbers are placed along the diagonal axes and response accuracy/efficiency are considered across the horizontal and vertical dimensions simultaneously. Participants indicated which number in each pair was largest using a joystick that only required unilateral input. The experiment was run in English using Arabic numerals. Results showed that directional SNAs have a vertical rather than horizontal dominance. A moderating factor was also found during post-hoc analysis, where response efficiency, but not accuracy, is conditional on a person’s native language being oriented the same as the language of the experiment, left to right. The dominance of the vertical orientation suggests adopting more vertical display formats for numbers may provide situational advantages, particularly for explicit magnitude comparisons, with some domains like flight controls and the stock market already using these in some cases.

Throughout their daily lives, animals and humans often switch between different behaviours. However, neuroscience research typically studies the brain while the animal is performing one behavioural task at a time, and little is known about how brain circuits represent switches between different behaviours. Here we tested this question using an ethological setting: two bats flew together in a long 135 m tunnel, and switched between navigation when flying alone (solo) and collision avoidance as they flew past each other (cross-over). Bats increased their echolocation click rate before each cross-over, indicating attention to the other bat1–9. Hippocampal CA1 neurons represented the bat’s own position when flying alone (place coding10–14). Notably, during cross-overs, neurons switched rapidly to jointly represent the interbat distance by self-position. This neuronal switch was very fast—as fast as 100 ms—which could be revealed owing to the very rapid natural behavioural switch. The neuronal switch correlated with the attention signal, as indexed by echolocation. Interestingly, the different place fields of the same neuron often exhibited very different tuning to interbat distance, creating a complex non-separable coding of position by distance. Theoretical analysis showed that this complex representation yields more efficient coding. Overall, our results suggest that during dynamic natural behaviour, hippocampal neurons can rapidly switch their core computation to represent the relevant behavioural variables, supporting behavioural flexibility.

The visual system processes sensory inputs sequentially, perceiving coarse information before fine details. Here we study the neural basis of coarse-to-fine processing and its computational benefits in natural vision. We find that primary visual cortical neurons in awake mice respond to natural scenes in a coarse-to-fine manner, primarily driven by individual neurons rapidly shifting their spatial frequency preference from low to high over a brief response period. This shift transforms the population response in a way that counteracts the statistical regularities of natural scenes, thereby reducing redundancy and generating a more efficient neural representation. The increase in representational efficiency does not occur in either dark-reared or anesthetized mice, which show significantly attenuated coarse-to-fine spatial processing. Collectively, these results illustrate that coarse-to-fine processing is state dependent, develops postnatally via visual experience, and provides a computational advantage by generating more efficient representations of the complex spatial statistics of ethologically relevant natural scenes.

Recent work has shown that number concepts activate both spatial and magnitude representations. According to the social co-representation literature which has shown that participants typically represent task components assigned to others together with their own, we asked whether explicit magnitude meaning and explicit spatial coding must be present in a single mind, or can be distributed across two minds, to generate a spatial-numerical congruency effect. In a shared go/no-go task that eliminated peripheral spatial codes, we assigned explicit magnitude processing to participants and spatial processing to either human or non-human co-agents. The spatial-numerical congruency effect emerged only with human co-agents. We demonstrate an inter-personal level of conceptual congruency between space and number that arises from a shared conceptual representation not contaminated by peripheral spatial codes. Theoretical implications of this finding for numerical cognition are discussed.

Significance Attention, the deep processing of select items, is one of the most important cognitive operations in the brain. But how does the brain control its attention? One proposed part of the mechanism is that the brain builds a model, or attention schema, that helps monitor and predict the changing state of attention. Here, we show that an artificial neural network agent can be trained to control visual attention when it is given an attention schema, but its performance is greatly reduced when the schema is not available. We suggest that the brain may have evolved a model of attention because of the profound practical benefit for the control of attention., In the attention schema theory (AST), the brain constructs a model of attention, the attention schema, to aid in the endogenous control of attention. Growing behavioral evidence appears to support the presence of a model of attention. However, a central question remains: does a controller of attention actually benefit by having access to an attention schema? We constructed an artificial deep Q-learning neural network agent that was trained to control a simple form of visuospatial attention, tracking a stimulus with an attention spotlight in order to solve a catch task. The agent was tested with and without access to an attention schema. In both conditions, the agent received sufficient information such that it should, theoretically, be able to learn the task. We found that with an attention schema present, the agent learned to control its attention spotlight and learned the catch task. Once the agent learned, if the attention schema was then disabled, the agent’s performance was greatly reduced. If the attention schema was removed before learning began, the agent was impaired at learning. The results show how the presence of even a simple attention schema can provide a profound benefit to a controller of attention. We interpret these results as supporting the central argument of AST: the brain contains an attention schema because of its practical benefit in the endogenous control of attention.

Feedback in the brain is thought to convey contextual information that underlies our flexibility to perform different tasks. Empirical and computational work on the visual system suggests this is achieved by targeting task-relevant neuronal subpopulations. We combine two tasks, each resulting in selective modulation by feedback, to test whether the feedback reflected the combination of both selectivities. We used visual feature-discrimination specified at one of two possible locations and uncoupled the decision formation from motor plans to report it, while recording in macaque mid-level visual areas. Here we show that although the behavior is spatially selective, using only task-relevant information, modulation by decision-related feedback is spatially unselective. Population responses reveal similar stimulus-choice alignments irrespective of stimulus relevance. The results suggest a common mechanism across tasks, independent of the spatial selectivity these tasks demand. This may reflect biological constraints and facilitate generalization across tasks. Our findings also support a previously hypothesized link between feature-based attention and decision-related activity., Feedback modulates visual neurons, thought to help achieve flexible task performance. Here, the authors show decision-related feedback is not only relayed to task-relevant neurons, suggesting a broader mechanism and supporting a previously hypothesized link to feature-based attention.

Key Points Question Are there associations between visual and cognitive impairment across multiple cognitive domains and multiple measures of vision? Findings In this longitudinal cohort study of 1202 older adults, worse visual acuity and stereo acuity impairment were associated with greater declines in language and memory domain scores, whereas worse contrast sensitivity was associated with declines in language, memory, attention, and visuospatial ability domain scores. Meaning These findings suggest that the association between vision and cognition differs by measure of vision and that impaired contrast sensitivity is associated with declines across more cognitive domains than visual acuity., This cohort study examines the association between visual and cognitive impairments across multiple cognitive domains using multiple measures of vision., Importance Associations between visual and global cognitive impairments have been previously documented, but there is limited research examining these associations between multiple measures of vision across cognitive domains. Objective To examine the association between vision and cognitive across multiple cognitive domains using multiple measures of vision. Design, Setting, and Participants This longitudinal cohort study used data from the Baltimore Longitudinal Study of Aging for 2003 to 2019. Participants in the current study were aged 60 to 94 years with vision and cognitive measures. Data analysis was performed from May 2020 to May 2021. Main Outcomes and Measures Cognitive function was measured across multiple domains, including language, memory, attention, executive function, and visuospatial ability. Cognitive domain scores were calculated as the mean of standardized cognitive test scores within each domain. Visual function was assessed using measures of visual acuity, contrast sensitivity, and stereo acuity at baseline. Results Analyses included 1202 participants (610 women [50.8%]; 853 White participants [71.0%]) with a mean (SD) age of 71.1 (8.6) years who were followed up for a mean (SD) of 6.9 (4.7) years. Worse visual acuity (per 0.1 logarithm of the minimal angle of resolution) at baseline was associated with greater declines in language (β, −0.0035; 95% CI, −0.007 to −0.001) and memory (β, −0.0052; 95% CI, −0.010 to −0.001) domain scores. Worse contrast sensitivity (per 0.1 log units) at baseline was associated with greater declines in language (β, −0.010; 95% CI, −0.014 to −0.006), memory (β, −0.009; 95% CI, −0.015 to −0.003), attention (β, −0.010; 95% CI, −0.017 to −0.003), and visuospatial ability (β, −0.010; 95% CI, −0.017 to −0.002) domain scores. Over the follow-up period, declines on tests of language (β, −0.019; 95% CI, −0.034 to −0.005) and memory (β, −0.032; 95% CI, −0.051 to −0.012) were significantly greater for participants with impaired stereo acuity compared with those without such impairment. Conclusions and Relevance These findings suggest that the association between vision and cognition differs between visual acuity, contrast sensitivity, and stereo acuity and that patterns of cognitive decline may differ by type of vision impairment, with impaired contrast sensitivity being associated with declines across more cognitive domains than other measures of visual functioning.

Down syndrome (DS) is the leading genetic cause of intellectual disability and causes early-onset dementia and cerebellar hypoplasia. The prevalence of attention deficit hyperactivity disorder is elevated in children with DS. The aneuploid DS mouse model “Ts65Dn” shows prominent brain phenotypes, including learning and memory deficits, cerebellar hypoplasia, and locomotor hyperactivity. Previous studies indicate that impaired Sonic hedgehog (Shh) signaling contributes to neurological phenotypes associated with DS and neurodegenerative diseases. However, because of a lack of working inducible Shh knock-in mice, brain region-specific Shh overexpression and its effects on cognitive function have not been studied in vivo. Here, with Gli1-LacZ reporter mice, we demonstrated that Ts65Dn had reduced levels of Gli1, a sensitive readout of Shh signaling, in both hippocampus and cerebellum at postnatal day 6. Through site-specific transgenesis, we generated an inducible human Shh knock-in mouse, TRE-bi-hShh-Zsgreen1 (TRE-hShh), simultaneously expressing dually-lipidated Shh-Np and Zsgreen1 marker in the presence of transactivator (tTA). Double transgenic mice “Camk2a-tTA;TRE-hShh” and “Pcp2-tTA;TRE-hShh” induced Shh overexpression and activated Shh signaling in a forebrain and cerebellum, respectively, specific manner from the perinatal period. Camk2a-tTA;TRE-hShh normalized locomotor hyperactivity and improved learning and memory in 3-month-old Ts65Dn, mitigated early-onset severe cognitive impairment in 7-month-old Ts65Dn, and enhanced spatial cognition in euploid mice. Camk2a-tTA;TRE-hShh cohort maintained until 600days old showed that chronic overexpression of Shh in forebrain from the perinatal period had no effect on longevity of euploid or Ts65Dn. Pcp2-tTA;TRE-hShh did not affect cognition but mitigated the phenotype of cerebellar hypoplasia in Ts65Dn. Our study provides the first in vivo evidence that Shh overexpression from the perinatal period protects DS brain integrity and enhances learning and memory in normal mice, indicating the broad therapeutic potential of Shh ligand for other neurological conditions. Moreover, the first inducible hShh site-specific knock-in mouse could be widely used for spatiotemporal Shh signaling regulation. Supplementary Information The online version contains supplementary material available at 10.1186/s40478-021-01237-z.

Topographical disorientation is the impairment or inability to successfully navigate in three-dimensional space. Differing topographical disorientation syndromes have been associated with distinct lesion sites in the acquired brain injury (ABI) literature. This meta-analysis attempted to investigate the relationship between lesion location and dysfunctions in specific navigational abilities resulting in topographical disorientation in individuals with ABI, as measured by their performance on experimental and neuropsychological tests. It was expected that focal lesions would be associated with a specific navigational deficit in one ability, with relative sparing of other navigational abilities. Twenty-six papers met the inclusion criteria for the analysis. Results indicated that ABI populations performed worse on all measures of navigation, with moderate to large effect sizes. Dysfunctions in three core navigational skills were consistent with the available lesion studies: a feature/landmark processing unit, a spatial processing unit, and a spatial/feature binding and associative learning unit. A sequential processing model was created to attempt to best represent the transfer of information between these units and the process by which navigational knowledge is generated. The model was then used to assess the validity of existing models of navigation and topographical disorientation.

This study aimed to draw a cross-task comparison on visuospatial processing in autism spectrum disorder without intellectual disability. Participants with autism spectrum disorder were matched with typically developing individuals on general intelligence and perceptual reasoning index. The two groups were subsequently compared on visuospatial processing speed, visuo-perceptual, visuo-constructive, and visuospatial working memory tasks. Our results revealed similar performances between autism spectrum disorder and typically developing individuals on measures of visuospatial processing speed and visuospatial working memory. The autism spectrum disorder group showed slower reaction times than the typically developing group in the visuo-perceptual task, when stimuli were characterized by a minimum level of perceptual cohesiveness, revealing weaker spatial integration abilities. Concerning the visuo-constructive domain, no differences between the autism spectrum disorder and the typically developing group emerged for the unsegmented condition, revealing that our participants with autism spectrum disorder were similar to the typically developing group in the local analysis of the stimuli. The discussion takes into account the role of individual differences on visuospatial intelligence, task requirements, and cognitive domains to clarify the visuospatial processing skills of individuals with autism spectrum disorder.

Reading causes widespread changes in the brain, but its effect on visual word representations is unknown. Learning to read may facilitate visual processing by forming specialized detectors for longer strings or by making word responses more predictable from single letters—that is, by increasing compositionality. We provided evidence for the latter hypothesis using experiments that compared nonoverlapping groups of readers of two Indian languages (Telugu and Malayalam). Readers showed increased single-letter discrimination and decreased letter interactions for bigrams during visual search. Importantly, these interactions predicted subjects’ overall reading fluency. In a separate brain-imaging experiment, we observed increased compositionality in readers, whereby responses to bigrams were more predictable from single letters. This effect was specific to the anterior lateral occipital region, where activations best matched behavior. Thus, learning to read facilitates visual processing by increasing the compositionality of visual word representations.

The common finding of better locally oriented perception among persons with autism spectrum disorder (ASD) is based on evidence from paradigms in which hierarchical stimuli are used to pit local and global processes against one another. However, in most cases, determining whether group differences reflect reduced global processing, enhanced local processing, or both is difficult. To provide more conclusive evidence for global perception in ASD, we examined shape formation and sensitivity to Gestalt heuristics. Children with persons with ASD and mental age matched typically developing children completed tasks in which the organization of contour segments into a shape was likely to depend on utilizing cues of closure, spatial proximity, and collinearity. In Experiment 1, search efficiency was measured, with the efficiency of the global organization indicated by the slope of the best-fitting linear reaction-time function over the number of presented items. In Experiment 2, contour integration task was administered, while Gestalt cues and the contour to background spacing ratio were manipulated independently. The findings indicated typical shape formation among the persons with ASD. Furthermore, certain interactive relations between Gestalt grouping cues that are known to govern shape formation in typically developing individuals determined the extraction of the global shape among the participants with ASD.

The human egocentric perception of approaching objects and the related perceptual processes have been of interest to researchers for several decades. This article gives a literature review on numerous studies that investigated the phenomenon when an object approaches an observer (or the other way around) with the goal to single out factors that influence the perceptual process. A taxonomy of metrics is followed by a breakdown of different experimental measurement methods. Thereinafter, potential factors affecting the judgment of approaching objects are compiled and debated while divided into human factors (e.g., gender, age, and driving experience), compositional factors (e.g., approaching velocity, spatial distance, and observation time), and technical factors (e.g., field of view, stereoscopy, and display contrast). Experimental findings are collated, juxtaposed, and critically discussed. With virtual-reality devices having taken a tremendous developmental leap forward in the past few years, they have been able to gain ground in experimental research. Therefore, special attention in this article is also given to the perception of approaching objects in virtual environments and put in contrast to the perception in reality.

Elementary school students often lack a conceptual understanding of linear measurement, which is revealed by their poor performance when the object to be measured is not aligned with the start of the ruler. Instead of correctly counting the units that correspond to the object (e.g., inches or centimeters), children often use 1 of 2 incorrect strategies: reading off the number that corresponds to the end of the object (the least-mature, read-off strategy) and counting the hash marks that flank the object (a more mature, but still incorrect, hash-mark strategy). We hypothesized that shifting to a more mature linear measurement strategy would require the ability to inhibit less-mature prepotent responses, such as read-off and hash-mark responses. In the present study, we predicted that children with better inhibitory control would be more likely to improve in their linear measurement strategy use over one year. Participants (n = 317) were in 1st through 3rd grades when they completed a linear measurement task that required measuring objects that were not aligned with the start of the ruler; they also completed an inhibitory control task and control measures (visuospatial working memory, arithmetic calculations, and number line estimation). One year later, they repeated the linear measurement task. Students with higher initial inhibitory control were more likely to adopt a more mature strategy over time. Moreover, inhibitory control was a significant predictor of strategy improvement over and above other cognitive measures, including visuospatial working memory and arithmetic calculation skill. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Feature-based attention is known to enhance visual processing globally across the visual field, even at task-irrelevant locations. Here, we asked whether attention to object categories, in particular faces, shows similar location-independent tuning. Using EEG, we measured the face-selective N170 component of the EEG signal to examine neural responses to faces at task-irrelevant locations while participants attended to faces at another task-relevant location. Across two experiments, we found that visual processing of faces was amplified at task-irrelevant locations when participants attended to faces relative to when participants attended to either buildings or scrambled face parts. The fact that we see this enhancement with the N170 suggests that these attentional effects occur at the earliest stage of face processing. Two additional behavioral experiments showed that it is easier to attend to the same object category across the visual field relative to two distinct categories, consistent with object-based attention spreading globally. Together, these results suggest that attention to high-level object categories shows similar spatially global effects on visual processing as attention to simple, individual, low-level features.

SIGNIFICANCE Glaucoma has been shown to impair hazard detection ability and increase crash risk compared to controls. Differences in visual search behavior of the driving scene may explain these differences; however, there has been limited investigation of this issue with inconsistent findings. PURPOSE Through eye movement tracking of older drivers with glaucoma, we explored their visual search behavior in comparison with controls while performing the DriveSafe, a slide recognition test purported to predict fitness to drive. METHODS Thirty-one drivers with glaucoma (mean age, 71.7 ± 6.3 years; average better-eye mean defect,-3 dB; average worse-eye mean defect,-12 dB) and 25 age-matched controls underwent measurements of their visual acuity, contrast sensitivity, visual fields, and useful field of view (visual processing speeds). Participants' eye movements were recorded while they completed the DriveSafe test, which consists of brief presentations of static, real-world driving scenes containing various road users (pedestrians, bicycles, vehicles). Participants reported the types, positions, and direction of travel of road users in each image; the score was the total number of correctly reported items (maximum, 128). RESULTS Drivers with glaucoma had significantly worse DriveSafe scores (P = .03), fixated on road users for shorter durations (P < .001), and exhibited smaller saccades (P = .02) compared with controls. For all participants, longer fixation times on road users (P < .001) was the eye movement measure most strongly associated with better DriveSafe scores; this relationship was not significantly different between groups. Useful field-of-view divided attention was the strongest visual predictor of DriveSafe scores. CONCLUSIONS Eye movement changes in the glaucoma group may reflect increased difficulty in identifying relevant objects in the visual scene, which may be related to their lower DriveSafe scores. Given the DriveSafe's potential utility in assessing drivers with visual impairment before on-road testing, further investigations on how DriveSafe performance and eye movement patterns compare to those during on-road driving are warranted.

Background Assistant equipment for the visually impaired has a white cane. If the information in the three-dimensional space is transmitted by sound, the blind can draw a three-dimensional space. Objective This study developed "Visual System," an ambulation aid/guide for the blind that transforms visual-spatial information into auditory information, and verified its utility. Unlike conventional systems, which are in essence simple collision-warning systems, Visual System helps the visually impaired to recreate their surroundings and to be cognizant of the location and proximity of obstacles. Methods Ten subjects with normal vision (mean age: 32.4 years; male-to-female ratio: 6 to 4) were selected for blind tests. The subjects were instructed to detect and avoid obstacles presented in various three-dimensional settings. Prior to the tests, experiments were conducted to determine the distance to each subject. Upon completion of Visual System-based detection training, obstacles were presented and tests conducted. For evaluation, the subjects' vertical position detection, horizontal position detection, distance detection, and overall performance success were each evaluated. Results The total performance scores ranged between 88 (lowest) and 100 (highest), with a mean score of 91.5. Conclusions The results indicate that Visual System as a product can assist the visually impaired in their daily functioning.

The allocentric lock theory (ALT) suggests that people with eating disorders have difficulties in multisensory integration in two reference frames—egocentric and allocentric, whereby the egocentric, but not allocentric, is impaired. This leads to a distorted body image that contributes to the development and maintenance of the disorder. The current study aimed to explore a facet of the ALT, namely, the visuo-spatial aspect, and its relation to cognitive flexibility in patients with anorexia nervosa (AN). Fifty-five participants took part in the study: 20 AN patients and 35 controls, matched by age and education. The object perspective taking test (OPTT) and the mental rotation test (MRT), tapping egocentric and allocentric representations, respectively, and a set-shifting task were administered. The brief symptom inventory was used to measure overall levels of distress. AN patients showed higher level of distress. They performed poorer on the OPTT and set-shifting task but not on the MRT. The OPTT and MRT were correlated for controls but not for AN patients, while the set-shifting task and body mass index were associated with the OPTT but not with the MRT for the AN patients. The findings support the ALT by demonstrating impaired visual egocentric representations and intact allocentric visual functions in AN patients, with cognitive flexibility associated only with the egocentric frame. Therefore, egocentric frame impairment in AN patients may be influenced by visual perception and cognitive flexibility deficiency. Level III: case-control analytic study.