Free-viewing Task Research Articles

Attentional processing biases to threat in schizophrenia: Evidence from a free-viewing task with emotional scenes

Attentional biases to threatening stimuli have been suggested to play a key role in the onset and course of schizophrenia. However, current research has not completely demonstrated this assumption. The aim of this eye-tracking study was to shed light on the underlying psychological mechanisms of schizophrenia by examining the attentional processing of socio-emotional information. Forty-four individuals with schizophrenia and 47 healthy controls were assessed in a 3-s free-viewing task with a social scene (i.e., happy, threatening, or neutral) in competition with a non-social one to determine the effects of emotional information on the different stages of the attentional processing. The location and latency of initial fixations (i.e., initial orienting), the firs-pass fixations and gaze duration (i.e., attentional engagement), and the percentage of total duration and total fixations (i.e., attentional maintenance) were analyzed. It was found that the schizophrenia group showed longer first-pass gaze duration, as well as higher percentage of total fixations and total duration toward threatening scenes in relation to the non-social ones, compared to controls. Therefore, an attentional bias toward threatening scenes in schizophrenia was found in the attentional maintenance and engagement, but not in the initial orienting of attention. Of note, the threat-related attentional bias was not associated with positive symptoms of schizophrenia. These findings offer empirical support to affective-information processing models stating that threatening information may confer psychological vulnerability to develop schizophrenia. Moreover, the results can improve psychological treatments, such as attentional bias modification paradigms or cognitive-behavior interventions managing maladaptive schemas related to threat.

The effects of attentional and interpretation biases on later pain outcomes among younger and older adults: A prospective study.

Studies examining the effect of biased cognitions on later pain outcomes have primarily focused on attentional biases, leaving the role of interpretation biases largely unexplored. Also, few studies have examined pain-related cognitive biases in elderly persons. The current study aims to fill these research gaps. Younger and older adults with and without chronic pain (N=126) completed an interpretation bias task and a free-viewing task of injury and neutral scenes at baseline. Participants' pain intensity and disability were assessed at baseline and at a 6-month follow-up. A machine-learning data-driven approach to analysing eye movement data was adopted. Eye movement analyses revealed two common attentional pattern subgroups for scene-viewing: an "explorative" group and a "focused" group. At baseline, participants with chronic pain endorsed more injury-/illness-related interpretations compared to pain-free controls, but they did not differ in eye movements on scene images. Older adults interpreted illness-related scenarios more negatively compared to younger adults, but there was also no difference in eye movements between age groups. Moreover, negative interpretation biases were associated with baseline but not follow-up pain disability, whereas a focused gaze tendency for injury scenes was associated with follow-up but not baseline pain disability. Additionally, there was an indirect effect of interpretation biases on pain disability 6months later through attentional bias for pain-related images. The present study provided evidence for pain status and age group differences in injury-/illness-related interpretation biases. Results also revealed distinct roles of interpretation and attentional biases in pain chronicity. Adults with chronic pain endorsed more injury-/illness-related interpretations than pain-free controls. Older adults endorsed more illness interpretations than younger adults. A more negative interpretation bias indirectly predicted pain disability 6months later through hypervigilance towards pain.

Effect of visual searching task on the postural stability of children

BACKGROUND: The relationship between gaze behavior and postural stability under distinct cognitive loads is still unclear in children. AIM: This study focuses on eye movements' effect on the children's postural stability by varying the visual tasks' attentional/cognitive demands. METHOD: Twenty young adults (23.4 years-old, ± 2.1) and sixteen children (10.3 years-old, ± 0.4) stand in semi- tandem position on a force plate, wearing a head-mounted eye-tracking while performing three 40 second-trials in the following order: stationary gaze task; free-viewing task; and visual searching task. RESULTS: Children showed a higher number of fixations during the stationary gaze task (p<0.0001), but this number was lower during free-viewing (p<0.004) and visual searching tasks (p<0.0001) when compared to young adults. Total fixation duration was lower in children than in young adults (p<0.0001) and higher during stationary gaze task than free-viewing (p<0.0001) and visual searching tasks (p<0.0001) for both groups. CONCLUSION: These results indicate that the performance of the visual searching task during the maintenance of a challenging stance may deteriorate children’s postural stability suggesting that the relationship between gaze behavior and postural control is not well developed around the age of 10 years.

Let Me Make You Happy, and I'll Tell You How You Look Around: Using an Approach-Avoidance Task as an Embodied Emotion Prime in a Free-Viewing Task.

The embodied approach of human cognition suggests that concepts are deeply dependent upon and constrained by an agent's physical body's characteristics, such as performed body movements. In this study, we attempted to broaden previous research on emotional priming, investigating the interaction of emotions and visual exploration. We used the joystick-based approach-avoidance task to influence the emotional states of participants, and subsequently, we presented pictures of news web pages on a computer screen and measured participant's eye movements. As a result, the number of fixations on images increased, the total dwell time increased, and the average saccade length from outside of the images toward the images decreased after the bodily congruent priming phase. The combination of these effects suggests increased attention to web pages' image content after the participants performed bodily congruent actions in the priming phase. Thus, congruent bodily interaction with images in the priming phase fosters visual interaction in the subsequent exploration phase.

Attentional Bias to High-Calorie Food in Binge Eaters With High Shape/Weight Concern.

Individuals with high shape/weight concern (SWC) place disproportionate emphasis on shape and weight in evaluating their self-worth, making them more vulnerable to body-related cues. Binge eaters (BE), who are obsessed with devouring high-calorie foods, would show severe symptomatology, especially when they have clinically high SWC. The present study attempted to elucidate how SWC influences binging based on attentional patterns toward high-calorie food cues. A total of 120 participants were selected and divided into four groups: (1) BE with high SWC, (2) BE with low SWC, (3) healthy controls (HC) with high SWC, and (4) HC with low SWC. BE and SWC status were respectively determined using the Eating Disorder Diagnostic Scale (DSM-5) and the Eating Disorder Examination Questionnaire. All participants completed the same free-viewing task, measuring initial fixation latency and total fixation duration. BE with high SWC showed attentional bias toward high-calorie food cues in terms of significantly faster initial fixation latency and longer total fixation duration, whereas BE with low SWC and the HC groups did not show any differences. The results revealed that SWC level makes unique contributions to BE's initial orienting bias toward and difficulty disengaging from high-calorie food cues. This may indicate that BE with high SWC merely worry about eating high-calorie food in a cognitive way, but not controlling actual binging behavior. The current study of attentional bias elucidated the role of SWC as a potential maintenance factor of being concerned and binging in BE.

Predicting ASD diagnosis in children with synthetic and image-based eye gaze data

As early intervention is highly effective for young children with autism spectrum disorder (ASD), it is imperative to make accurate diagnosis as early as possible. ASD has often been associated with atypical visual attention and eye gaze data can be collected at a very early age. An automatic screening tool based on eye gaze data that could identify ASD risk offers the opportunity for intervention before the full set of symptoms is present. In this paper, we propose two machine learning methods, synthetic saccade approach and image based approach, to automatically classify ASD given children’s eye gaze data collected from free-viewing tasks of natural images. The first approach uses a generative model of synthetic saccade patterns to represent the baseline scan-path from a typical non-ASD individual and combines it with the real scan-path as well as other auxiliary data as inputs to a deep learning classifier. The second approach adopts a more holistic image-based approach by feeding the input image and a sequence of fixation maps into a convolutional or recurrent neural network. Using a publicly-accessible collection of children’s gaze data, our experiments indicate that the ASD prediction accuracy reaches 67.23% accuracy on the validation dataset and 62.13% accuracy on the test dataset.

Attentional biases to emotional scenes in schizophrenia: An eye-tracking study

Attentional biases to emotional information may play a key role in the onset and course of schizophrenia. The aim of this experiment was to examine the attentional processing of four emotional scenes in competition (happy, neutral, sad, threatening) in 53 patients with schizophrenia and 51 controls. The eye movements were recorded in a 20-seconds free-viewing task. The results were: (i) patients showed increased attention on threatening scenes, compared to controls, in terms of attentional engagement and maintenance; (ii) patients payed less attention to happy scenes than controls, in terms of attentional maintenance; (iii) whereas positive symptoms were associated with a late avoidance of sad scenes, negative symptoms were associated with heightened attention to threat. The findings suggest that a threat-related bias and a lack of sensitivity to positive information may represent an underlying psychological mechanism of schizophrenia. Importantly, schizophrenia symptoms modulated the attentional biases, which has aetiological and therapeutic implications.

Automatic attentional bias toward high-calorie food cues and body shape concerns in individuals with a high level of weight suppression: Preliminary findings

This study aimed to investigate differences in attentional processes in response to food cues and body shape concerns according to an individual's level of weight suppression. Among 470 women in their 20s, nonobese participants (body mass index [BMI] <25 kg/m2) were divided into two groups according to weight history. If the difference between their highest weight ever and current weight was greater than 10%, they were assigned to the high level of weight suppression (H-WS) group (n = 24); if it was less than 5%, they were assigned to the low level of weight suppression (L-WS) group (n = 29). Self-reported body shape concerns and bulimia nervosa symptoms were assessed. Visual attentional processes were recorded using an eye tracker while participants completed a free-viewing task composed of pairs of high- and low-calorie food cues. After controlling for current BMI, the H-WS group reported higher body shape concerns and higher levels of bulimia nervosa symptoms than did the L-WS group. In the free-viewing task, after controlling for current BMI, body shape concerns, and bulimia nervosa symptoms, the H-WS group had a significantly longer dwell time for high-calorie compared with low-calorie food cues than did the L-WS group, and this difference was observed for the first 1000 ms. Compared with individuals with low weight suppression, the vulnerability to bulimia nervosa symptoms observed in individuals with high weight suppression may be associated with a higher automatic approach tendency toward high-calorie foods after adjusting for body shape concerns.

Properties of visually guided saccadic behavior and bottom-up attention in marmoset, macaque, and human.

Saccades are stereotypic behaviors whose investigation improves our understanding of how primate brains implement precise motor control. Furthermore, saccades offer an important window into the cognitive and attentional state of the brain. Historically, saccade studies have largely relied on macaques. However, the cortical network giving rise to the saccadic command is difficult to study in macaques because relevant cortical areas lie in deep sulci and are difficult to access. Recently, a New World monkey. the marmoset, has garnered attention as an alternative to macaques because of advantages including its smooth cortical surface. However, adoption of the marmoset for oculomotor research has been limited due to a lack of in-depth descriptions of marmoset saccade kinematics and their ability to perform psychophysical tasks. Here, we directly compare free-viewing and visually guided behavior of marmoset, macaque, and human engaged in identical tasks under similar conditions. In the video free-viewing task, all species exhibited qualitatively similar saccade kinematics up to 25° in amplitude although with different parameters. Furthermore, the conventional bottom-up saliency model predicted gaze targets at similar rates for all species. We further verified their visually guided behavior by training them with step and gap saccade tasks. In the step paradigm, marmosets did not show shorter saccade reaction time for upward saccades whereas macaques and humans did. In the gap paradigm, all species showed similar gap effect and express saccades. Our results suggest that the marmoset can serve as a model for oculomotor, attentional, and cognitive research while we need to be aware of their difference from macaque or human.NEW & NOTEWORTHY We directly compared the results of a video free-viewing task and visually guided saccade tasks (step and gap) among three different species: marmoset, macaque, and human. We found that all species exhibit qualitatively similar saccadic kinematics and saliency-driven saccadic behavior albeit with different parameters. Our results suggest that the marmoset possesses similar neural mechanisms to macaque and human for saccadic control, and it is an appropriate model to study neural mechanisms for active vision and attention.

Effective schizophrenia recognition using discriminative eye movement features and model-metric based features

Eye movement abnormalities have been effective biomarkers that provide the possibility of distinguishing patients with schizophrenia from healthy controls. The existing methods for measuring eye movement abnormalities mostly focus on synchronic parameters, such as fixation duration and saccade amplitude, which can be directly obtained from eye movement data, while lack of considering more thorough features. In this paper, to better characterize eye-tracking dysfunction, we create a dataset containing 100 images with eye movement data of 40 patients and 30 healthy controls via a free-viewing task, and propose two types of features for effective schizophrenia recognition, i.e. the hand-crafted discriminative eye movement features and the model-metric based features via utilizing the computational models of fixation prediction and the metrics of evaluating their prediction performance. Using the proposed features, two commonly used classifiers including support vector machine and random forest have been trained for classification between patients and controls. Experimental results demonstrate the effectiveness of the proposed features for improving classification performance, and the potential that our method can serve as an alternative and promising approach for the computer-aided diagnosis of schizophrenia.

Primate Amygdalo-Nigral Pathway for Boosting Oculomotor Action in Motivating Situations.

SummaryA primary function of the primate amygdala is to modulate behavior based on emotional cues. To study the underlying neural mechanism, we first inactivated the amygdala locally and temporarily by injecting a GABA agonist. Then, saccadic eye movements and gaze were suppressed only on the contralateral side. Next, we performed optogenetic activation after injecting a viral vector into the amygdala. Optical stimulation in the amygdala excited amygdala neurons, whereas optical stimulation of axon terminals in the substantia nigra pars reticulata inhibited nigra neurons. Optical stimulation in either structure facilitated saccades to the contralateral side. These data suggest that the amygdala controls saccades and gaze through the basal ganglia output to the superior colliculus. Importantly, this amygdala-derived circuit mediates emotional context information, whereas the internal basal ganglia circuit mediates object value information. This finding demonstrates a basic mechanism whereby basal ganglia output can be modulated by other areas conveying distinct information.

Artificial Faces Predict Gaze Allocation in Complex Dynamic Scenes.

Both low-level physical saliency and social information, as presented by human heads or bodies, are known to drive gaze behavior in free-viewing tasks. Researchers have previously made use of a great variety of face stimuli, ranging from photographs of real humans to schematic faces, frequently without systematically differentiating between the two. In the current study, we used a Generalized Linear Mixed Model (GLMM) approach to investigate to what extent schematic artificial faces can predict gaze when they are presented alone or in competition with real human faces. Relative differences in predictive power became apparent, while GLMMs suggest substantial effects for real and artificial faces in all conditions. Artificial faces were accordingly less predictive than real human faces but still contributed significantly to gaze allocation. These results help to further our understanding of how social information guides gaze in complex naturalistic scenes.

Predicting artificial visual field losses: A gaze-based inference study.

Visual field defects are a world-wide concern, and the proportion of the population experiencing vision loss is ever increasing. Macular degeneration and glaucoma are among the four leading causes of permanent vision loss. Identifying and characterizing visual field losses from gaze alone could prove crucial in the future for screening tests, rehabilitation therapies, and monitoring. In this experiment, 54 participants took part in a free-viewing task of visual scenes while experiencing artificial scotomas (central and peripheral) of varying radii in a gaze-contingent paradigm. We studied the importance of a set of gaze features as predictors to best differentiate between artificial scotoma conditions. Linear mixed models were utilized to measure differences between scotoma conditions. Correlation and factorial analyses revealed redundancies in our data. Finally, hidden Markov models and recurrent neural networks were implemented as classifiers in order to measure the predictive usefulness of gaze features. The results show separate saccade direction biases depending on scotoma type. We demonstrate that the saccade relative angle, amplitude, and peak velocity of saccades are the best features on the basis of which to distinguish between artificial scotomas in a free-viewing task. Finally, we discuss the usefulness of our protocol and analyses as a gaze-feature identifier tool that discriminates between artificial scotomas of different types and sizes.

Looking at Facial Expressions of 12 Persons in One Scene: Anaysis of Eye Movement Patterns in Free-viewing Task

Looking at Facial Expressions of 12 Persons in One Scene: Anaysis of Eye Movement Patterns in Free-viewing Task

Free-viewing multi-stimulus eye tracking task to index attention bias for alcohol versus soda cues: Satisfactory reliability and criterion validity

Cognitive -motivational models point to attention bias (AB) as an important factor in the persistence of problematic drinking behavior. Unfortunately, the measures that have been used to examine AB in addiction typically showed poor psychometric properties. To bring research on AB a critical step further it would be crucial to develop tasks with acceptable reliability and construct validity. Recently, Lazarov and colleagues (2016) developed a multi-stimulus free-viewing task (participants were free to look at any part of the screen and there was no secondary task involved) that showed excellent psychometric properties in the context of social anxiety as well as depression. We, therefore, adapted this task and examined its psychometric quality within the context of alcohol use. Participants with varying levels of alcohol use (N = 100) were presented with 54 matrices each containing 8 alcoholic and 8 non-alcoholic drinks. Each matrix was presented for 6 s. First fixation (100 ms) location and latency and total dwell time were assessed for alcohol and soda pictures. Assessment of AB, craving, and alcohol use (problems) was repeated after 3–8 days. Specifically, the dwell-time based AB-measure showed excellent internal reliability and considerable stability. Supporting the validity of the current AB-measures, it was found that participants with higher scores on craving and alcohol problems (i) dwelt longer on alcohol stimuli, and (ii) more often showed a first fixation on alcohol, whereas (iii) stronger craving was associated with shorter latency of first alcohol fixations. The AB-measure showed promising psychometric properties. Thus, this free-viewing eye-tracking task seems a welcome new tool for being used in future research on AB in addiction.

Relations between Eye Movement, Postural Sway and Cognitive Involvement in Unprecise and Precise Visual Tasks

We studied eye and body movements in 16 healthy young adults who performed visual tasks in upright stance. Our objective was to investigate whether these movements could be functionally related to each other when performing a precise visual task requiring large ecological gaze shifts. We also questioned the influence of an additional counting task on these relations. The participants performed searching (precise), free-viewing (unprecise) and gaze-fixation (basic) either alone or in counting silently backwards in sevens. For the search task, the participants had to visually locate as many targets as possible in the images. For the free-viewing task, they had to watch images randomly. Based on a recent model, we expected to find negative correlations between eye and center of pressure and/or body (lower back, neck, head) movements only in the search tasks. The double search–counting task was expected to increase the number of negative correlations. The results confirmed both hypotheses in both search tasks, with relations mainly between eye and head movements (89% of the time). The subjective cognitive involvement (significantly higher in searching than in free-viewing and gaze-fixation) was significantly related to all (100%) and to half (50%) of these previous correlations in search–counting and searching, respectively. Complementarily, the participants rotated their segments and oscillated more in searching than free-viewing and more in both tasks than in gaze-fixation. This study confirmed that precise visual tasks may require the brain to control synergistic relations between eye and body movements instead of individual eye and body movements.

Attentional bias for emotional faces in depressed and non-depressed individuals: an eye-tracking study.

Current assessment tools for clinicians in mental health evaluation relies mostly on patient self-report and clinician's judgement. Recent studies suggest that affective disorders are correlated to attentional bias for visual information. This study used eye-tracking technology to measure attentional bias for faces in depressed and non-depressed individuals. The experiment was based on a free-viewing task of pair of faces including 4 types of expressions: neutral, sad, happy and angry. 69 individuals took part in this study. All the participants completed the Beck Depression Inventory II (BDI-II) to evaluate the severity of depressive symptoms. The attention indexes were total time for eye events, total fixation duration, ratio of total fixation and eye events, and fixation duration on each face. The results showed that depressed individuals have a significant (p = 0.005) difference in the total time of eye events (302.4±41.2) compared to non-depressed individuals (331.5±39.3) and revealed a tendency to disengage from emotional stimuli with differences in the total fixation in pair of faces. The study demonstrated that the use of eye-tracking is a valuable tool to asses attentional bias and important technology that could be used to improve diagnosis technics.

Systematic Review and Meta-Analysis: Eye-Tracking of Attention to Threat in Child and Adolescent Anxiety.

Attention biases for threat may reflect an early risk marker for anxiety disorders. Yet questions remain regarding the direction and time-course of anxiety-linked biased attention patterns in youth. A meta-analysis of eye-tracking studies of biased attention for threat was used to compare the presence of an initial vigilance toward threat and a subsequent avoidance in anxious and nonanxious youths. PubMed, PsycARTICLES, Medline, PsychINFO, and Embase were searched using anxiety, children and adolescent, and eye-tracking-related key terms. Study inclusion criteria were as follows: studies including participants≤18 years of age; reported anxiety using standardized measures; measured attention bias using eye tracking with a free-viewing task; comparison of attention toward threatening and neutral stimuli; and available data to allow effect size computation for at least one relevant measure. A random effects model estimated between- and within-group effects of first fixations toward threat and overall dwell time on threat. Thirteen eligible studies involving 798 participants showed that neither youths with or without anxiety showed significant bias in first fixation to threat versus neutral stimuli. However anxious youths showed significantly less overall dwell time on threat versus neutral stimuli than nonanxious controls (g= -0.26). Contrasting with adult eye-tracking data and child and adolescent data from reaction time indices of attention biases to threat, there was no vigilance bias toward threat in anxious youths. Instead, anxious youths were more avoidant of threat across the time course of stimulus viewing. Developmental differences in brain circuits contributing to attention deployment to emotional stimuli and their relationship with anxiety are discussed.

Positive Relations Between Vision and Posture in the Fixation Task Performed Upright.

In an upright stance, individuals sway in unpredictable ways. Their eyes also move in unpredictable ways in fixation tasks. The objective of this study was to analyze visual functions, postural control, and cognitive involvement in stationary gaze. A total of 14 healthy young adults performed a fixation task and a free-viewing task (three trials per task, 45s per trial). As expected, the results showed many (n = 32) significant positive Pearson correlation coefficients between the eye and center of pressure/body (head, neck, and lower back) movements in the fixation task. In the free-viewing task, the correlations were nonsignificant. Only 3 of the 32 significant correlations (9.4%) were significantly related to cognitive involvement (measured with a subjective questionnaire). These results indirectly strengthened the validity of the synergistic model of postural control.

The relationship between attentional processing of emotional information and personality: A comparison between older and younger adults.

Older adults have been found to focus more on positive and less on negative information compared to younger adults. Yet, results on this attentional positivity effect are inconsistent. Since personality has been related to attentional processing in younger adults, we explored whether (mal)adaptive personality traits are also linked to the occurrence of the positivity effect measured with eye tracking paradigms. We performed two studies with different experimental tasks and recruited for each study 60 community dwelling younger (aged 24–50) and 60 older (age 65–91) adults. We found some indication for a positivity effect with a free-viewing task (study 2), but not with a task measuring engagement and disengagement with emotional information (study 1). Although this effect should be interpreted with caution, it corroborates evidence that the positivity effect is more robust in situations without cognitive constraints. No evidence was found for personality traits to be related to the occurrence of the effect. Further research is needed to further clarify conditions that influence older adults’ attention for emotional information.