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Several studies have investigated visual processing impairment in schizophrenia. The literature on visual exploration has described restricted scanning in schizophrenia patients. This gaze behavior is characterized by increased fixation duration, a reduced scan path length and avoidance of salient features of the face with emotional content. The aim of this paper is to give an insight on the latest update on scan path deficit. Abnormal gaze exploration was replicated in various visual stimuli. This review describes gaze patterns with stimuli that imply minimal to high cognitive process: figures, objects, faces, and scenes. Interestingly, schizophrenia patients have shown cognitive flexibility by modulating gaze scanning when they are involved in an active assignment. We will also consider scanning abnormalities in real-life environment and discuss the potential therapeutic use of eye tracking in schizophrenia. The therapeutic application of eye tracking in schizophrenia is a young emerging field in psychiatry research. The recent remediation program is based on the reorientation of visual attention on the salient features of faces. For now, this program has shown encouraging results. Further studies are needed to explore behavior in real-world situations to complement laboratory measurements to move toward a full understanding of the mechanisms underlying atypical scanning in patients with schizophrenia., (Copyright © 2020 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)

Background: Eye movement abnormalities have been identified in schizophrenia; however, their relevance to cognition is still unknown. In this study, we explored the general relationship between eye movements and cognitive function., Methods: The three eye movement measures (scanpath length, horizontal position gain, and duration of fixations) that were previously reported to be useful in distinguishing subjects with schizophrenia from healthy subjects, as well as Wechsler Adult Intelligence Scale-III (WAIS-III) scores, were collected and tested for association in 113 subjects with schizophrenia and 404 healthy subjects., Results: Scanpath length was positively correlated with matrix reasoning and digit symbol coding in subjects with schizophrenia and correlated with vocabulary and symbol search in healthy subjects. Upon testing for interaction effects of diagnosis and scanpath length on correlated WAIS-III scores, a significant interaction effect was only observed for matrix reasoning. The positive correlation between scanpath length and matrix reasoning, which was specific to subjects with schizophrenia, remained significant after controlling for demographic confounders such as medication and negative symptoms. No correlation was observed between the two other eye movement measures and any of the WAIS-III scores., Conclusions: Herein, we reveal novel findings on the association between eye-movement-based measures of visual exploration and cognitive scores requiring visual search in subjects with schizophrenia and in healthy subjects. The association between scanpath length and matrix reasoning, a measure of perceptual organization in subjects with schizophrenia, implies the existence of common cognitive processes, and subjects with longer scanpath length may be advantageous in performance of perceptual organization tasks., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The question of whether animals perceive pictures as representation of real objects remains still unsolved. Object-picture perception is generally studied requiring animals to learn some information about real objects and transfer that knowledge to the pictorial domain, or vice versa. Here, we tackle the issue of object-picture perception from a different perspective, examining visual exploration behavior of two naïve macaque monkeys during free-viewing of objects and pictures of these objects on a computer monitor. Our main finding is that monkeys looked spontaneously longer at object rather than picture stimuli. However, we find striking similarities in temporal dynamics of gaze allocation within the time course of a single stimulus presentation, as well as in habituation rates within and across behavioral sessions. We also highlight differences between stimulus types in terms of spatial gaze patterns and looking strategies. Stimulus features that attract overt attention during spontaneous visual exploration are thus better predicted for object stimuli by a visual saliency model. Moreover, we provide evidence for a consistency in stimulus preference for objects and pictures, suggesting a correspondence of in how macaques perceive objects and their pictorial stimuli. Taken together, our data suggest that macaque monkeys exhibit evidence for correspondence between objects and pictures. This validates spontaneous visual exploration as a method for studying object-picture correspondence without a need for extensive behavioral training. We discuss the potential advantages of using object over picture stimuli in the context of studies on visual cognition., (Copyright © 2015. Published by Elsevier B.V.)

Background: Co-speech gestures are part of nonverbal communication during conversations. They either support the verbal message or provide the interlocutor with additional information. Furthermore, they prompt as nonverbal cues the cooperative process of turn taking. In the present study, we investigated the influence of co-speech gestures on the perception of dyadic dialogue in aphasic patients. In particular, we analysed the impact of co-speech gestures on gaze direction (towards speaker or listener) and fixation of body parts. We hypothesized that aphasic patients, who are restricted in verbal comprehension, adapt their visual exploration strategies., Methods: Sixteen aphasic patients and 23 healthy control subjects participated in the study. Visual exploration behaviour was measured by means of a contact-free infrared eye-tracker while subjects were watching videos depicting spontaneous dialogues between two individuals. Cumulative fixation duration and mean fixation duration were calculated for the factors co-speech gesture (present and absent), gaze direction (to the speaker or to the listener), and region of interest (ROI), including hands, face, and body., Results: Both aphasic patients and healthy controls mainly fixated the speaker's face. We found a significant co-speech gesture × ROI interaction, indicating that the presence of a co-speech gesture encouraged subjects to look at the speaker. Further, there was a significant gaze direction × ROI × group interaction revealing that aphasic patients showed reduced cumulative fixation duration on the speaker's face compared to healthy controls., Conclusion: Co-speech gestures guide the observer's attention towards the speaker, the source of semantic input. It is discussed whether an underlying semantic processing deficit or a deficit to integrate audio-visual information may cause aphasic patients to explore less the speaker's face., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The majority of a football referee's time is spent assessing open-play situations, yet little is known about how referees search for information during this uninterrupted play. The aim of the current study was to examine the exploratory gaze behaviour of elite and sub-elite football referees in open-play game situations. Four elite (i.e. national) and eight sub-elite (i.e. regional) referees officiated an in-situ football match while wearing a mobile eye-tracker to assess their gaze behaviour. Both referential head and eye movements (i.e. moving gaze away from and then back to the ball) were measured. Results showed gaze behaviour was characterised overall by more referential head than eye movements (~75 vs 25%), which were of longer duration (~950 vs 460 ms). Moreover, elite referees employed faster referential movements (~640 vs 730 ms), spending less time with their gaze away from the ball (carrier) than the sub-elite referees. Crucially, both the referential head and eye movements were coordinated relative to key events in the match, in this case passes, showing that referees anticipate the passes to ensure that the referential movements did not occur during passes, rather before or after. The results further our understanding of the coordinative gaze behaviours that underpin expertise in officiating. [ABSTRACT FROM AUTHOR]

Visual exploration paradigms involving object arrays have been used to examine salience of social stimuli such as faces in ASD. Recent work suggests performance on these paradigms may associate with clinical features of ASD. We evaluate metrics from a visual exploration paradigm in 4-to-11-year-old children with ASD (n = 23; 18 males) and typical development (TD; n = 23; 13 males). Presented with arrays containing faces and nonsocial stimuli, children with ASD looked less at (p = 0.002) and showed fewer fixations to (p = 0.022) faces than TD children, and spent less time looking at each object on average (p = 0.004). Attention to the screen and faces correlated positively with social and cognitive skills in the ASD group (ps <.05). This work furthers our understanding of objective measures of visual exploration in ASD and its potential for quantifying features of ASD. [ABSTRACT FROM AUTHOR]

• Driving simulator and eye tracker allow to assess dynamically the characteristics of driver's visual exploration of the driving surrounding. • In driving condition, all the participants show a reduction of the density of the visual field (VF), but only Glaucoma and Elderly ones show a smaller eccentricity of the VF. • Glaucoma participants have a more dynamic gaze than the other participants and they share their gaze more equally between the main ZVIs (Zones of Visual Interest). • Using a classification algorithm, it is possible to identify the group which a participant belongs to on the only basis of the visual exploration characteristics. Assessing the driving skills of people with cognitive or visual impairments is often complex. The analysis of visual exploration strategies can be a good solution to identify the implementation or not of good strategies of information search in the visual scene (adaptation and compensation). In this study, we compared the visual exploration behaviours of 26 healthy, 19 glaucoma and 21 elderly participants. For this purpose, we used a driving simulator for which a visual field measurement test had been adapted to obtain measurements in static and dynamic conditions. The dynamics of the gaze was also measured. Our results showed that each of the three groups of participants had specific characteristics of visual exploration. Using a classification algorithm, we were able to show that it was possible to identify the group which a participant belonged to on the basis of the visual exploration's characteristics. This finding opens the door to many applications in the context of driving assistance and training. [ABSTRACT FROM AUTHOR]

The present study examined the validity and reliability of two new soccer tests: the Passing Accuracy Test (PAT), which assesses ball passing accuracy in combination with visual stimulus recognition and the Passing and Visual Recognition test (PVR), which assesses player's space detection skill in a 360 degrees range along with the frequency and the accuracy of ball passing technique. Participants were allocated in four (4) groups based on their age: the Under 11 (U11) group consisted of 101 players, the Under 14 (U14) group consisted of 100 players, the Under 17 (U17) group consisted of 118 players and the Adults (AD) group consisted of 43 players. The typical error, the limits of agreement and the ICC of PAT and PVR test were examined. The results of the study showed high validity and reliability for both tests with the exception in PAT for adult group (ICC = 0.33–0.83; P < 0.05). Therefore, both tests could be valuable tools to assess the accuracy of ball passing technique and the space detection skill in players of different ages. [ABSTRACT FROM AUTHOR]

Similarity measuring methods are widely adopted in a broad range of visualization applications. In this work, we address the challenge of representing human perception in the visual analysis of scatterplots by introducing a novel deep-learning-based approach, ScatterNet, captures perception-driven similarities of such plots. The approach exploits deep neural networks to extract semantic features of scatterplot images for similarity calculation. We create a large labeled dataset consisting of similar and dissimilar images of scatterplots to train the deep neural network. We conduct a set of evaluations including performance experiments and a user study to demonstrate the effectiveness and efficiency of our approach. The evaluations confirm that the learned features capture the human perception of scatterplot similarity effectively. We describe two scenarios to show how ScatterNet can be applied in visual analysis applications. [ABSTRACT FROM AUTHOR]

Selective spatial attention is a crucial cognitive process that guides us to the behaviorally relevant objects in a complex visual world by using exploratory eye movements. The spatial location of objects, their (bottom-up) saliency and (top-down) relevance is assumed to be encoded in one "attentional priority map" in the brain, using different egocentric (eye-, head- and trunk-centered) spatial reference frames. In patients with hemispatial neglect, this map is supposed to be imbalanced, leading to a spatially biased exploration of the visual environment. As a proof of concept, we altered the visual saliency (and thereby attentional priority) of objects in a naturalistic scene along a left-right spatial gradient and investigated whether this can induce a bias in the exploratory eye movements of healthy humans (n = 28; all right-handed; mean age: 23 years, range 19–48). We developed a computerized mask, using high-end "gaze-contingent display (GCD)" technology, that immediately and continuously reduced the saliency of objects on the left—"left" with respect to the head (body-centered) and the current position on the retina (eye-centered). In both experimental conditions, task-free viewing and goal-driven visual search, this modification induced a mild but significant bias in visual exploration similar to hemispatial neglect. Accordingly, global eye movement parameters changed (reduced number and increased duration of fixations) and the spatial distribution of fixations indicated an attentional bias towards the right (rightward shift of first orienting, fixations favoring the scene's outmost right over left). Our results support the concept of an attentional priority map in the brain as an interface between perception and behavior and as one pathophysiological ground of hemispatial neglect. [ABSTRACT FROM AUTHOR]

Individuals with autism spectrum disorder (ASD) often display enhanced attention to detail and exhibit restricted behavior. However, due to a lack of comprehensive eye-movement modeling techniques, it is currently unknown whether these behavioral effects are also evident during scene viewing (i.e., detailed visual inspection and restricted visual exploration). Free-viewing eye-tracking data from observation of everyday photographic scenes were recorded during 2 experiments involving high-functioning adolescents with ASD and matched typically developing (TD) controls (Experiment 1, ASD n = 14; TD n = 22; Experiment 2, ASD n = 16; TD n = 23). Data from both experiments were combined and analyzed using 5 novel methods of eye-tracking, time-course analysis, enabling detailed characterization of viewing strategies. Participants' verbal descriptions of scenes were also assessed. Scenes either contained a centrally positioned person whose face was in full view or contained no centrally positioned face. For both types of scene, ASD participants displayed significantly less exploration of new areas over time compared with their TD peers. Analyses of scan-path length and recursion suggested a greater tendency to explore areas close to the current fixation in the ASD group, termed visual persistence. Differences were not accounted for by fixation rate. Significantly more areas within the scenes were also missing from the verbal descriptions in the ASD group. Differences were observed for both scene types, suggesting a domain-general difference rather than a specific impairment related to face processing. The observed characteristic viewing patterns may explain relative superior processing of local level information in individuals with ASD. [ABSTRACT FROM AUTHOR]

According to the direct matching hypothesis, perceived movements automatically activate existing motor components through matching of the perceived gesture and its execution. The aim of the present study was to test the direct matching hypothesis by assessing whether visual exploration behavior correlate with deficits in gestural imitation in left hemisphere damaged (LHD) patients. Eighteen LHD patients and twenty healthy control subjects took part in the study. Gesture imitation performance was measured by the test for upper limb apraxia (TULIA). Visual exploration behavior was measured by an infrared eye-tracking system. Short videos including forty gestures (20 meaningless and 20 communicative gestures) were presented. Cumulative fixation duration was measured in different regions of interest (ROIs), namely the face, the gesturing hand, the body, and the surrounding environment. Compared to healthy subjects, patients fixated significantly less the ROIs comprising the face and the gesturing hand during the exploration of emblematic and tool-related gestures. Moreover, visual exploration of tool-related gestures significantly correlated with tool-related imitation as measured by TULIA in LHD patients. Patients and controls did not differ in the visual exploration of meaningless gestures, and no significant relationships were found between visual exploration behavior and the imitation of emblematic and meaningless gestures in TULIA. The present study thus suggests that altered visual exploration may lead to disturbed imitation of tool related gestures, however not of emblematic and meaningless gestures. Consequently, our findings partially support the direct matching hypothesis. [ABSTRACT FROM AUTHOR]

Three-dimensional data arrays (collections of individual data matrices) are increasingly prevalent in modern data and pose unique challenges to pattern extraction and visualization. This article introduces a biclustering technique for exploration and pattern detection in such complex structured data. The proposed framework couples the popular plaid model together with tools from functional data analysis to guide the estimation of bicluster responses over the array. We present an efficient algorithm that first detects biclusters that exhibit strong deviations for some data matrices, and then estimates their responses over the entire data array. Altogether, the framework is useful to home in on and display underlying structure and its evolution over conditions/time. The methods are scalable to large datasets, and can accommodate a variety of dynamic patterns. The proposed techniques are illustrated on gene expression data and bilateral trade networks. Supplementary materials are available online. [ABSTRACT FROM PUBLISHER]

In coastal regions, water, wind, gravitation, vegetation, and human activity continuously alter landscape surfaces. Visualizations are important for understanding coastal landscape evolution and its driving processes. Visualizing change in highly dynamic coastal terrain poses a formidable challenge; the combination of natural and anthropogenic forces leads to cycles of retreat and recovery and complex morphology of landforms. In recent years, repeated high-resolution laser terrain scans have generated a time series of point cloud data that represent landscapes at snapshots in time, including the impacts of major storms. In this article, we build on existing approaches for visualizing spatial–temporal data to create a collection of perceptual visualizations to support coastal terrain evolution analysis. We extract terrain features and track their migration; we derive temporal summary maps and heat graphs that quantify the pattern of elevation change and sediment redistribution and use the space–time cube concept to create visualizations of terrain evolution. The space–time cube approach allows us to represent shoreline evolution as an isosurface extracted from a voxel model created by stacking time series of digital elevation models. We illustrate our approach on a series of Light Detection and Ranging surveys of sandy North Carolina barrier islands. Our results reveal terrain changes of shoreline and dune ridge migration, dune breaches and overwash, the formation of new dune ridges, and the construction and destruction of homes, changes which are due to erosion and accretion, hurricanes, and human activities. These events are all visualized within their geographic and temporal contexts. [ABSTRACT FROM PUBLISHER]

Effective visual exploration is required for many activities of daily living and instruments to assess visual exploration are important for the evaluation of the visual and the oculomotor system. In this article, the development of a new instrument to measure central and peripheral target recognition is described. The measurement setup consists of a hemispherical projection which allows presenting images over a large area of ±90° horizontal and vertical angle. In a feasibility study with 14 younger (21–49years) and 12 older (50–78years) test persons, 132 targets and 24 distractors were presented within naturalistic color photographs of everyday scenes at 10°, 30°, and 50° eccentricity. After the experiment, both younger and older participants reported in a questionnaire that the task is easy to understand, fun and that it measures a competence that is relevant for activities of daily living. A main result of the pilot study was that younger participants recognized more targets with smaller reaction times than older participants. The group differences were most pronounced for peripheral target detection. This test is feasible and appropriate to assess the functional field of view in younger and older adults. [ABSTRACT FROM AUTHOR]

High-dimensional data sets containing hundreds of variables are difficult to explore, as traditional visualization methods often are unable to represent such data effectively. This is commonly addressed by employing dimensionality reduction prior to visualization. Numerous dimensionality reduction methods are available. However, few reduction approaches take the importance of several structures into account and few provide an overview of structures existing in the full high-dimensional data set. For exploratory analysis, as well as for many other tasks, several structures may be of interest. Exploration of the full high-dimensional data set without reduction may also be desirable. This paper presents flexible methods for exploratory analysis and interactive dimensionality reduction. Automated methods are employed to analyse the variables, using a range of quality metrics, providing one or more measures of ‘interestingness’ for individual variables. Through ranking, a single value of interestingness is obtained, based on several quality metrics, that is usable as a threshold for the most interesting variables. An interactive environment is presented in which the user is provided with many possibilities to explore and gain understanding of the high-dimensional data set. Guided by this, the analyst can explore the high-dimensional data set and interactively select a subset of the potentially most interesting variables, employing various methods for dimensionality reduction. The system is demonstrated through a use-case analysing data from a DNA sequence-based study of bacterial populations. [ABSTRACT FROM AUTHOR]

We present a model for building, visualizing, and interacting with multiscale representations of information visualization techniques using hierarchical aggregation. The motivation for this work is to make visual representations more visually scalable and less cluttered. The model allows for augmenting existing techniques with multiscale functionality, as well as for designing new visualization and interaction techniques that conform to this new class of visual representations. We give some examples of how to use the model for standard information visualization techniques such as scatterplots, parallel coordinates, and node-link diagrams, and discuss existing techniques that are based on hierarchical aggregation. This yields a set of design guidelines for aggregated visualizations. We also present a basic vocabulary of interaction techniques suitable for navigating these multiscale visualizations. [ABSTRACT FROM AUTHOR]

Abstract: Reading and visual exploration impairments in unilateral homonymous hemianopia are well-established clinical phenomena. Spontaneous adaptation of eye-movements to the visual field defect leads to improved reading and visual exploration performance. Yet, it is still unclear whether oculomotor adaptation to visual field loss is task-specific or whether there is a transfer of adaptation-related improvements between reading and visual exploration. We therefore simulated unilateral homonymous hemianopia in healthy participants and explored the specificity with which oculomotor adaptation to this pure visual-sensory dysfunction during uninstructed reading or visual exploration practice leads to improvements in both abilities. Our findings demonstrate that there is no transfer of adaptation-related changes of eye-movements and performance improvements between reading and visual exploration. Efficient oculomotor adaptation to visual field loss is highly specific and task-dependent. [Copyright &y& Elsevier]

To help tracking all molecules made in a typical medicinal chemistry project, we have developed an algorithm to generate a maximum common framework (MCF) hierarchy and an interactive tool for its visualization and analysis. By identifying all unique frameworks for a set of molecules and all molecules containing each framework, we were able to simplify the MCF hierarchy build up steps and, as a result, speed up the entire process significantly. By allowing compounds to be assigned to multiple MCFs, users can easily remove bad branching nodes and concentrate on interesting ones. MCF hierarchies provide an effective and intuitive visualization for tracking medicinal chemistry lead optimization projects. We will provide examples to illustrate its usefulness. [ABSTRACT FROM AUTHOR]

Remote sensors are widely used in coastal morphodynamic research, and users are often confronted with abundant data sensors generated by these sensors. These data, if properly explored, can be used to study and manage many coastal features and processes that are not well understood. As an example, we present the exploration of rip channels. Coastal data sets are currently explored using animated image sequences. Users are dissatisfied, however, because exploration remains largely a subjective and time-consuming process. In particular, detecting the presence and evolution of relatively small, highly dynamic rip channels has proved difficult. This article examines how the visual exploration of rip objects can be improved. We first look at the factors limiting exploratory use of conventional animations for rip studies and argue that two main factors are responsible: data complexity and animation design based on images that mimic reality. Then we present an example of how the current approach to visualizing time series of coastal images can be improved by computational methods, particularly by feature tracking. Next, we describe a visualization prototype and discuss the representational, data-mining, and interactive functionality resulting from such a combination in an environment dedicated to the exploration of dynamic objects. [ABSTRACT FROM AUTHOR]

The analysis and exploration of multidimensional and multivariate data is still one of the most challenging areas in the field of visualization. In this paper, we describe an approach to visual analysis of an especially challenging set of problems that exhibit a complex internal data structure. We describe the interactive visual exploration and analysis of data that includes several (usually large) families of function graphs f,(x, t). We describe analysis procedures and practical aspects of the interactive visual analysis specific to this type of data (with emphasis on the function graph characteristic of the data). We adopted the well-proven approach of multiple, linked views with advanced interactive brushing to assess the data. Standard views such as histograms, scatterplots, and parallel coordinates are used to jointly visualize data. We support iterative visual analysis by providing means to create complex, composite brushes that span multiple views and that are constructed using different combination schemes. We demonstrate that engineering applications represent a challenging but very applicable area for visual analytics. As a case study, we describe the optimization of a fuel injection system in diesel engines of passenger cars. [ABSTRACT FROM AUTHOR]

The use of new representation forms and interactive means to visualize geospatial data requires an understanding of the impact of the visual tools used for data exploration and knowledge construction. Use and usability assessment of implemented methods and tools is an important part of our efforts to build this understanding. Based on an approach to combine visual and computational methods for knowledge discovery in large geospatial data, an integrated visualization‐geocomputation environment has been developed based on the Self‐Organizing Map (SOM), the map and the parallel coordinate plot. This environment allows patterns and attribute relationships to be explored. A use and usability assessment is conducted to evaluate the ability of each of these visual representations to meet user performance and satisfaction goals. In the test, different representations are compared while exploring a socio‐demographic dataset. [ABSTRACT FROM AUTHOR]