Simple Visual Search Research Articles

Visuo-Attentional and Phonological Deficits Explored in French Students with Dyslexia: Eye Movements Recorded during a Phonological Lexical Decision Task.

Whether dyslexia is caused by phonological or attentional dysfunction remains a widely debated issue. To enrich this debate, we compared the eye movements of 32 French university students with (14 students) and without (18 students) dyslexia while performing a delayed phonological lexical decision task on 300 visually presented stimuli. The processing stimuli involved either a lexical (i.e., words) or a non-lexical route relying on a grapheme-phoneme correspondence (pseudohomophones and pseudowords), while other stimuli involved only a visual search (consonant and symbol sequences). We recorded the number of fixations, the duration of the first fixation and the amplitude of saccades made on the stimuli. Compared to the controls, the participants with dyslexia made more fixations while reading regardless of the type of stimulus (lexical and non-lexical). Crucially, the participants with dyslexia exhibited longer first fixations in particular while reading phonologically challenging stimuli such as pseudohomophones and pseudowords compared to stimuli involving a simple visual search (consonants, symbols). Taken together, these results suggest that both visual and phonological impairments may be implicated in dyslexia, supporting the hypothesis that dyslexia is a multifactorial deficit.

88 Determining the Eye-Tracking Strategies Used in the Game “Spot the Missing Object (SMO)” by Simulator Malingerers, ADHD, and Non-ADHD

Objective:Typical evaluations of adult ADHD consist of behavior self-report rating scales, cognitive or intellectual functioning measures, and specific measures designed to measure attention. Boone (2009) suggested monitoring continuous effort is essential throughout psychological assessments. However, very few research studies have contributed to malingering literature on the ADHD population. Many studies have reported the adequate use of symptom validity tests, which assess effortful performance in ADHD evaluations (Jasinski et al., 2011; Sollman et al., 2010; Schneider et al., 2014). Because of the length of ADHD assessments, individuals are likely to become weary and tired, thus impacting their performance. This study investigates the eye movement strategies used by a clinical ADHD population, non-ADHD subjects, and malingering simulators when playing a common simple visual search task.Participants and Methods:A total of 153 college students participated in this study. To be placed in the ADHD group, a participant must endorse four or more symptoms on the ASRS (N = 37). To be placed in the non-ADHD, participants should have endorsed no ADHD symptoms (N = 43). Participants that did not meet the above criteria for ADHD and not-ADHD were placed in an Indeterminate group and were not included in the analysis. A total of 20 participants were instructed to fake symptoms related to ADHD during the session. A total of twelve Spot the Difference images were used as the visual picture stimuli. Sticky by Tobii Pro (2020) was used for the collection of eye-movement data was utilized. Sticky by Tobii Pro is an online self-service platform that combines online survey questions with an eye-tracking webcam, allowing participants to see images from their home computers.Results:Results indicated on the participants classified as Malingering had a significantly Visit Count (M = 17.16; SD= 4.99) compared to the ADHD(M = 12.53; SD= 43.92) and not-ADHD groups (M =11.51; SD=3.23). Results also indicated a statistically significant Area Under the Curve (AUC) = .784; SE = .067; p -.003; 95% CI = .652-.916. Optimal cutoffs suggest a Sensitivity of 50% with a False Positive Rate of 10%.Conclusions:Results indicated that eye-tracking technology could help differentiate simulator malingerers from non-malingerers with ADHD. Eye-tracking research’ relates to a patchwork of fields more diverse than the study of perceptual systems. Due to their close relation to attentional mechanisms, the study’s results can provide an insight into cognitive processes related to malingering performance.

Attentional selection is a sufficient cause for visual working memory interference.

Visual attention and visual working memory (VWM) are intertwined processes that allow navigation of the visual world. These systems can compete for highly limited cognitive resources, creating interference effects when both operate in tandem. Performing an attentional task while maintaining a VWM load often leads to a loss of memory information. These losses are seen even with very simple visual search tasks. Previous research has argued that this may be due to the attentional selection process, of choosing the target item out of surrounding nontarget items. Over two experiments, the current study disentangles the roles of search and selection in visual search and their influence on a retained VWM load. Experiment 1 revealed that, when search stimuli were relatively simple, target-absent searches (which did not require attentional selection) did not provoke memory interference, whereas target-present search did. In Experiment 2, the number of potential targets was varied in the search displays. In one condition, participants were required to select any one of the items displayed, requiring an attentional selection but no need to search for a specific item. Importantly, this condition led to memory interference to the same extent as a condition where a single target was presented among nontargets. Together, these results show that the process of attentional selection is a sufficient cause for interference with a concurrently maintained VWM load.

Feature Attention as a Control Mechanism for the Balance of Speed and Accuracy in Visual Search

Finding an object amongst a cluttered visual scene is an everyday task for humans but presents a fundamental challenge to computational models performing this feat. Previous attempts to model efficient visual search have focused on locating targets as swiftly as possible, but so far have not considered balancing the costs of lengthy searches against the costs of making errors. Here, we propose a neuro-inspired model of visual search that offers an attention-based control mechanism for this speed-accuracy trade-off. The model combines a goal-based fixation policy, which captures human-like behaviour on a simple visual search task, with a deep neural network that carries out the target detection step. The neural network is patched with a target-based feature attention model previously applied to standalone classification tasks. In contrast to image classification, visual search introduces a time component, which places an additional demand on the model to minimise the time cost of the search whilst also maintaining acceptable accuracy. The proposed model balances these two costs by modulating the attentional strength given to characteristic features of the target class, thereby minimising an associated cost function. The model offers a method for optimising the costs of visual search and demonstrates the value of a decision theoretic approach to modelling more complex visual tasks involving attention.

Looking for a word or for its meaning? The impact of induction tasks on adolescents' visual search for verbal material.

An eye-tracking experiment was conducted to examine whether the pre-activation of different word-processing pathways by means of semantic versus perceptual induction tasks could modify the way adults and 11- to 15-year-old adolescents searched for single target words within displays of nine words. The presence within the search displays of words either looking like the target word or semantically related to the target word was manipulated. The quality of participants' lexical representations was evaluated through three word-identification and vocabulary tests. Performing a semantic induction task rather than a perceptual one on the target word before searching for it increased search times by 15% in all age groups, reflecting an increase in both the number and duration of gazes directed to non-target words. Moreover, performing the semantic induction task increased the impact of distractor words that were semantically related to the target word on search efficiency. Participants' search efficiency increased with age because of a progressive increase in the quality of adolescents' lexical representations, which allowed participants to more quickly reject the distractors on which they fixated. Indeed, lexical quality scores explained 43% of the variance in search times independently of participants' age. In the simple visual search task used in this study, fostering semantic word processing through the semantic induction task slowed down visual search. However, the literature suggests that semantic induction tasks could, in contrast, help people find information more easily in more complex verbal environments where the meaning of words must be accessed to find task-relevant information.

The Effect of Spatial Uncertainty on Visual Search in Older School-Aged Children with and without ADHD.

Numerous studies support that simple visual search tests may not be sufficient to differentiate children with and without attention-deficit/hyperactivity disorder (ADHD), especially for older school-aged children. This study aimed to explore whether the high spatial uncertainty visual search tasks can effectively discriminate older school-aged children with ADHD from their typically developing (TD) peers. In a randomized, two-period crossover design, 122 school-aged children (61 ADHD and 61 TD subjects), aged 10-12years old, were measured using comparable visual search tasks with structured and unstructured layouts. First, the discriminant effectiveness of unstructured visual search tasks, which are associated with high-level spatial uncertainty, is superior to structured ones. Second, combining accuracy and speed into a Q score is a more sensitive measure than accuracy or time calculated alone in visual search tasks. A more in-depth ROC analysis showed that all variables could accurately identify ADHD from their TD peers under unstructured visual search tasks, with the index of the Q score performing best (AUR = 0.956). Third, the development of detectability, which represents the ability to distinguish between target and non-target, is approaching maturity in 10-12-year-old children with ADHD. However, these children showed severe deficits in dealing with disorganized distractors when performing visual search tasks with high-level spatial uncertainty. The findings of this study support that older school-aged children with ADHD demonstrate less efficient search performance than their TD peers in complex/difficult visual search tasks, especially under higher spatial uncertainty.

Research on visual search behaviors of basketball players at different levels of sports expertise

This study aims to examine visual search strategies of skilled basketball players in an anticipation task. This study selected 48 experienced and inexperienced basketball players. The participants were grouped into novice and expert groups based on their experience. The participants were asked to look at series of pictures of offensive patterns of play in a basketball game from a third person perspective and chose one of the three options: passing, shooting and break through. This study measured and recorded the response time, key pressing results, and eye movements. Eye movement data were recorded using the Tobii X-3 120 eye tracker. The results showed that, the expert group demonstrated superior anticipation performance, and were more accuracy. In addition, the results showed that participants in the expert group and faster predicted the offensive way faster than the novice group. The results also showed that experienced basketball players employed a simple and efficient visual search strategy including greater fixation counts and longer fixation duration on more informative areas than the novice group. Furthermore, the visualization metrics showed that the expert group had a more concise fixation trajectory and focused mainly on key information area. Generally, expert players exhibited a more efficient and effective visual search strategy demonstrating better performance on anticipation tasks.

Effect of Cognitive Training on Lower Limb Muscular Activity in Older Adults With Balance Impairment During Walking

Purpose: The purpose of this study was to compare the effects of two different approaches of dual-task training and executive training on lower limb muscular activity in older adults with balance impairment. Methods: This was a quasi-experimental study performed with a pre-test and post-test method. Thirty old adults (Mean±SD age=73.8±4.6 y, height=1.65±0.06 m, weight=69.17±12.67 kg) were randomly assigned to one of the three groups: two experimental groups included Cognitive Dual-Task training (CDT; participants did exercises under the dual-task condition with cognitive tasks, such as forward counting, simple visual search task, etc.) and Executive Function training (EF; included a mixture of 20 tasks involving working memory tasks, inhibitory and speed of processing tasks), and a control group. The training session lasted 45 min and was held three times a week for eight weeks. Gait muscle activity under single-task and Dual-Task (DT) conditions was recorded before and after training. Results: during the stance phase of normal walking, the amplitude of Electromyography (EMG) activity of right Tibialis Anterior (TA) muscle in the post-test was about 32% lower than that in the pre-test in the CDT group (P=0.011), and no statistically significant change was between pre- and post-training in the EF and control groups (P>0.05). During the swing phase of DT walking, the amplitude of EMG activity of the right Vastus Lateralis (VL) muscle in the post-test was about 15.5% higher than that in the pre-test in the CDT group (P=0.013), and in the right VL muscle during the post-test was lower than that in the pre-test in the EF group (P=0.01). In the CDT group, right ankle co-contraction during the stance phase in the post-test was statistically different from that in the pre-test. In all three groups, muscular EMG asymmetry demonstrated no statistically significant change between pre- and post-training measures (P>0.05). Conclusion: Overall, both training groups showed similar muscular activity in the post-test than pre-test; however, in the EF training group, walking velocity improved more than that in the CDT group. Therefore, because of improvements in both walking velocity and muscle activities after EF training, this training mode is suggested for older adults.

COMPARATIVE CHARACTERISTICS OF SENSORIMOTOR REACTIONS IN THE TASKS OF VISUAL SEARCH IN STUDENTS OF VARIOUS AGE GROUPS

The formation of perception and voluntary attention functions is the basis for the development of the child's cognitive activity. The implementation features of the voluntary attention processes on the models of simple and complex visual search in groups of subjects with an age range from 8 to 18 years old were studied. Reaction time, errors (goal's omissions, false alarms), time for cognitive processes, correlations and features of attention efficiency in subjects with various academic performances were analyzed. The search time for a single element in a random location of an empty grid decreases with age. Errors such as "false alarm" prevail in younger age groups. The effectiveness of visual search can be one of the criteria for academic performance. Young men and women with low academic performance make significantly more mistakes such as "false alarm" in visual search tasks. The front-parietal attention system is the main one for the implementation of sensorimotor reactions. The maturation of this system can be the basis for increasing the attention effectiveness with age.

Visual Task Characterization for Exploratory Search

Humans are living in the age of big data, advanced analytics, and human information interaction. The tremendous growth of ‘the data' presents enormous challenges to information-seeking. A naïve user adapts several strategies (e.g., analytical search, search by analogy, etc.) to aggregate the knowledge. Augmented visualization plays a pivotal role via visual cognitive support in user searches (i.e., simple visual search, visual exploration, etc.). Though it is hard for a user to look for specific tasks or visual metaphors, as evaluation of visual task is rarely undertaken, it is unclear what role, if any, information visualizations play in the user search. In this paper, a visual taxonomy is adopted to systematically review key visualization tools to understand the visual tasks and inherent functions and viability. The key contribution is to trace the current trends and advancements on the dimensions (i.e., visual accomplishments and visual implications) and to assert that annotations will provide a vision on the state of exploratory visual analytics, evolving frameworks, and tools.

Immersive 3D Virtual Reality Cancellation Task for Visual Neglect Assessment: A Pilot Study.

Background: Unilateral spatial neglectis an attention disorder frequently occurring after a right-hemispheric stroke. Neglect results in a reduction in qualityof life and performance in activities of daily living. With current technical improvements in virtual reality (VR) technology, trainingwith stereoscopic head-mounted displays (HMD) has become a promising new approach for the assessment and the rehabilitation of neglect. The focus of this pilot study was to develop and evaluate a simple visual search task in VR for HMD. The VR system was tested regarding feasibility, acceptance, and potential adverse effects in healthy controls and right-hemispheric stroke patients with and without neglect.Methods: The VR system consisted of two main components, a head-mounted display to present the virtual environment, and a hand-held controller for the interaction with the latter. The task followed the rationale of diagnostic paper-pencil cancellation tasks; i.e., the participants were asked to search targets among distractors. However, instead of a two-dimensional setup, the targets and distractors were arranged in three dimensions, in a sphere around the subject inside its field of view. Usability and acceptance of the task, as well as the performance in the latter, were tested in 15 right-hemispheric subacute stroke patients (10 of whom with and five of whom without unilateral spatial neglect; mean age: 67.1 ± 10.5 years) and 35 age-matched healthy controls.Results: System usability and acceptance were rated as high both in stroke patients and healthy controls, close to the maximum score of the questionnaire scale. No relevant adverse effects occurred. There was a high correlation (r = 0.854, p = 0.002) between the Center of Cancellation [an objective neglect measure) calculated from a paper-pencil cancellation task (Sensitive Neglect Test (SNT)] and the newly developed VR cancellation task.Conclusion: Overall, the developed visual search task in the tested VR system is feasible, well-accepted, enjoyable, and does not evoke any significant negative effects, both for healthy controls and for stroke patients. Findings for task performance show that the ability of the VR cancellation to detect neglect in stroke patients is similar to paper-pencil cancellation tasks.

N-Back Task Training Helps to Improve Post-error Performance.

Improved performance on working memory (WM) through training has been widely expected to transfer to other domains. Recent studies have proposed that WM training could enhance the autonomous coordination of WM processes. Based on the shared processes between WM and error processing, our present study explored the transfer effect of 15 days of training on post-error performance, during the n-back task, compared to a simple visual search task. Participants were randomly assigned to either the training (N = 22) or control (N = 18) group. We found that WM training successfully improved WM performance. After training, compared with the control group, the training group showed a significant reduction in post-error slowing (PES); however, post-error accuracy and the flanker effect were not modulated by WM training. Moreover, we observed a significant, negative correlation between the changes in PES and WM from pretest to posttest and classified two groups based on these changes in PES with 70% accuracy. Thus, in our present sample, WM training improved post-error performance. We propose that the skill of controlling information flow, developed during WM training, is transferable to other tasks and discuss the implications of current findings for understanding the generation of PES.

The confirmation and prevalence biases in visual search reflect separate underlying processes.

Research by Rajsic, Wilson, and Pratt (2015, 2017) suggests that people are biased to use a target-confirming strategy when performing simple visual search. In 3 experiments, we sought to determine whether another stubborn phenomenon in visual search, the low-prevalence effect (Wolfe, Horowitz, & Kenner, 2005), would modulate this confirmatory bias. We varied the reliability of the initial cue: For some people, targets usually occurred in the cued color (high prevalence). For others, targets rarely matched the cues (low prevalence). High cue-target prevalence exacerbated the confirmation bias, indexed via search response times (RTs) and eye-tracking measures. Surprisingly, given low cue-target prevalence, people remained biased to examine cue-colored letters, even though cue-colored targets were exceedingly rare. At the same time, people were more fluent at detecting the more common, cue-mismatching targets. The findings suggest that attention is guided to "confirm" the more available cued target template, but prevalence learning over time determines how fluently objects are perceptually appreciated. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Visual Search in the older age: Understanding cognitive decline

Did I miss that sign post? - Where did I leave my glasses? Older adults increasingly report experiencing such cognitive failures. Consistent with this experience, age-related decline has been demonstrated in standard visual search experiments. These standard laboratory tasks typically use simple stimulus material and brief trial structures that are well-designed to isolate some specific cognitive process component. Real-world tasks, however, while built of these smaller components, are complex and extend over longer periods of time. In this talk, I will compare findings on age differences in simple visual search experiments to our recent findings from extended hybrid (visual and memory) search and foraging tasks. The extended search tasks resemble complex real-world tasks more closely and enable us to look at age differences in attention, memory, and strategic process components within one single task. Surprisingly, after generalized age-related slowing of reaction times (RT) was controlled for, the extended search tasks did not reveal any age-specific deficits in attention and memory functions. However, we did find age-related decline in search efficiency, which were explained by differences between age groups in foraging strategies. I will discuss how these new results challenge current theories on cognitive aging and what impact they could have on the neuropsychological assessment of age-related cognitive changes.

Stimulus- and Response-locked Posterior Contralateral Negativity Bisect Cognitive Operations in Visual Search.

We explored the flow of information during visual search by examining activity indexing visual attention (N2pc) and the subsequent processing of the selected objects in visual short-term memory (SPCN) time-locked to stimulus presentation and to the motor response. We measured event-related activity at posterior sites (PO7/PO8) for 96 participants during a simple visual search task. A response-locked posterior contralateral negativity (RLpcN) was observed with a scalp distribution similar to that of the N2pc and SPCN. The RLpcN was compared with the stimulus-locked activity (N2pc and SPCN) across experimental manipulations (targets were either closer or farther from fixation in visual space, and the response was either more frequent [75%] or less frequent [25%]) and across response speeds (EEG data were separated into tertiles by RT both within-subjects and between-subjects). The leading edge and early portion of the RLpcN appeared to reflect the initial deployment of attention (N2pc), whereas the later portion (up to peak amplitude) reflected subsequent processing of visual information (SPCN). SPCN and RLpcN also had similar modulations in amplitude for both analyses. Moreover, whereas very small N2pc and SPCN onset latency differences were observed when data were separated into tertiles by RT, there were large onset differences for the RLpcN, with earlier RLpcN onsets for longer RTs, suggesting that RT variance is in large determined by processing after the initial deployment of attention. The results show how we can bisect processing responsible for variations in RT relative to the onset of visual spatial attention.

Differences in Search Mechanics for Anxious Individuals and Individuals with an Autism Spectrum Disorder During Real-World Visual Search Tasks

Introduction: Superiority in visual search tasks is often seen in individuals with autism spectrum disorders (ASD) and is frequently attributed to perceptual differences in visual processing (either a preference for local processing or a difficulty with global processing). Recent research, however, has suggested that these differences may instead be related to an atypical attentional system. In addition, research has also suggested that individuals with ASD may no longer demonstrate a visual search advantage when those searches involve real-world scenes. Similarly, differences in visual search have been seen in individuals with anxiety, compared to non-anxious typically developing (TD) individuals. Despite the high prevalence of anxiety symptoms in ASD, the extent to which these altered visual search profiles overlap had not been investigated. Method: Individuals with ASD (N = 30), anxiety (N = 27), and typically developing (TD) individuals (N = 49) completed two simple visual search tasks (41 trials of each) with real-world scenes (one to find a digit superimposed on the scene and the other to find an object placed in a contextually-relevant location). Eye movements were recorded to quantify three stages of the search process: initiation time (start of trial to first saccade), scan time (first saccade to first target fixation), and verification time (first target fixation to response). Results: Across conditions, the ASD group required longer initiation time than the anxiety and TD groups. Both the ASD and anxiety groups had a longer scan time and verification time than the TD group but were similar to each other. Conclusion: With real-world scenes, those with ASD and anxiety require more time for real-world visual search. The only aspect of search mechanics uniquely difficult for those with ASD is initiation time. This is consistent with theories proposing a difficulty disengaging attention as underlying real-world visual search difficulties in those with ASD. Meeting abstract presented at VSS 2018

Temporal Limitations of the Standard Leaky Integrate and Fire Model

The leaky integrate and fire model of neural spiking has been used extensively to simulate saccadic responses in a variety of tasks from visual search to simple reaction times. Although it has been tested for its neural spiking accuracy and its spatial prediction of fixations in visual salience, it has not been well tested for its temporal accuracy. Saccade generation invariably results in a positively skewed distribution of saccadic reaction times over large numbers of samples, yet we show that the LIF algorithm tends to produce a distribution shifted to shorter fixations (in comparison with human data) in its classic implementation. Further, parameter optimization using a genetic algorithm and Nelder–Mead method does improve the fit of the resulting distribution, but is still unable to match temporal distributions of human responses in a simple visual search task. Further analysis revealed, that the LIF algorithm produces discrete reaction times instead of distributions. Aggregated over many pictures they may be treated as a distribution although the form of this distribution depends on the input images used to create it.

Performance on naturalistic virtual reality tasks depends on global cognitive functioning as assessed via traditional neurocognitive tests

ABSTRACTThis investigation sought to understand whether performance in naturalistic virtual reality tasks for cognitive assessment relates to the cognitive domains that are supposed to be measured. The Shoe Closet Test (SCT) was developed based on a simple visual search task involving attention skills, in which participants have to match each pair of shoes with the colors of the compartments in a virtual shoe closet. The interaction within the virtual environment was made using the Microsoft Kinect. The measures consisted of concurrent paper-and-pencil neurocognitive tests for global cognitive functioning, executive functions, attention, psychomotor ability, and the outcomes of the SCT. The results showed that the SCT correlated with global cognitive performance as measured with the Montreal Cognitive Assessment (MoCA). The SCT explained one third of the total variance of this test and revealed good sensitivity and specificity in discriminating scores below one standard deviation in this screening tool. These findings suggest that performance of such functional tasks involves a broad range of cognitive processes that are associated with global cognitive functioning and that may be difficult to isolate through paper-and-pencil neurocognitive tests.

Does within-person variability predict errors in healthy adults aged 18-90?

This study investigated within-person variability on basic psychomotor tasks in relation to errors on a higher order cognitive task. We were interested in whether more variable individuals were more prone to making errors, and whether this relationship varied with age. Variability was assessed using simple and choice reaction time, while errors of omission (misses) and commission (false alarms) were obtained from simple and complex visual search tasks. Data from 557 participants aged 18-90 years were included in the analysis. Greater variability was associated with more misses, and distribution analyses showed that slower responses were behind this effect. Variability was also associated with false alarms, but the pattern was inconsistent. Taking age into account revealed that the association between variability and misses in the simple visual search condition was stronger in older (aged 65-90 years) participants. The results suggest the relationship between greater variability and errors of omission (misses) may be related to inattention. Measures of variability may therefore provide valuable insights into individual differences in error rates and, more broadly, may also offer early warning of persons who are more prone to errors in visual search.

Evidence for an attentional component of inhibition of return in visual search.

Inhibition of return (IOR) is typically described as an inhibitory bias against returning attention to a recently attended location as a means of promoting efficient visual search. Most studies examining IOR, however, either do not use visual search paradigms or do not effectively isolate attentional processes, making it difficult to conclusively link IOR to a bias in attention. Here, we recorded ERPs during a simple visual search task designed to isolate the attentional component of IOR to examine whether an inhibitory bias of attention is observed and, if so, how it influences visual search behavior. Across successive visual search displays, we found evidence of both a broad, hemisphere-wide inhibitory bias of attention along with a focal, target location-specific facilitation. When the target appeared in the same visual hemifield in successive searches, responses were slower and the N2pc component was reduced, reflecting a bias of attention away from the previously attended side of space. When the target occurred at the same location in successive searches, responses were facilitated and the P1 component was enhanced, likely reflecting spatial priming of the target. These two effects are combined in the response times, leading to a reduction in the IOR effect for repeated target locations. Using ERPs, however, these two opposing effects can be isolated in time, demonstrating that the inhibitory biasing of attention still occurs even when response-time slowing is ameliorated by spatial priming.