Visual Cognitive Tasks Research Articles

Dopaminergic modulation of visual attention in the prefrontal cortex

An essential cognitive ability that enables creatures to interpret pertinent information from their surroundings only is visual attention. The prefrontal cortex (PFC) is involved in modulating visual attention, and this review focuses on the dopaminergic aspects of this process. The PFC is crucial for top-down attention management, improving visual responses, and coordinating neural activity. This is especially true of the frontal eye field (FEF). Dopamine is an important neuromodulator that directly influences the PFC's visual signal processing by adjusting sensory input and the variability of neuronal response. The substantia nigra (SN) and ventral tegmental area (VTA) send dopaminergic pathways to the prefrontal cortex, where D1 and D2 receptors have different functions in attention regulation. Dopamine receptor modification has been shown in studies involving rodents and primates to have a major effect on visual attention and cognitive task performance. The exact mechanisms underlying dopamine's involvement in executive control are still unknown despite a great deal of research, which calls for more study, especially in rodent models. The present review highlights the significance of dopamine in the domain of high-level cognitive regulation and advocates for more investigation to clarify its mechanisms in visual attention.

Effects of visual and auditory cognitive tasks on postural balance in adolescents with intellectual disability: A comparative analysis of trained versus non-trained individuals

This study aimed to investigate the influence of visual and auditory cognitive tasks on postural balance in adolescents with intellectual disabilities (ID). Participants included two groups: a trained group (n = 11) with experience in athletic activities and a sedentary group (n = 14). The experiment used a comparative cross-sectional design, with data collection involving single-task (ST) and Visual dual-task (VDT), and auditory dual-task (ADT) conditions in both firm and foam surface conditions. Cognitive tests included the Working Memory Test (WMT) and the Selective Attention Test (SAT). Results revealed that the trained group demonstrated significantly superior balance performance (p < 0.05). During the SAT, VDT conditions had lower center of pressure (CoP) values than ADT conditions in the sedentary group (p < 0.01), this result was observed in the training group only in the WMT, suggesting greater postural instability during ADT. These findings highlight the complex relationship between cognitive function and motor control in adolescents with ID, highlighting the potential benefits of regular physical activity interventions to improve postural balance abilities in this population.

Balance Performance in Young Adults With Hearing Aids: How Can It Be Affected by the Visual Cognitive Task?

The aim of this study was to investigate the effect of a visual cognitive additional task on balance performance in young adults with hearing aids (HAs). Twenty young adult HA users and 20 controls were recruited for the study. Participants were asked to stand on a force plate using computerized dynamic posturography and perform a Sensory Organization Test (SOT) as a balance task under single-task (ST) and dual-task (DT) conditions. The DT condition involved performing a visual cognitive task (Backward Digit Recall) while maintaining balance. Balance performance was measured using equilibrium scores under four different conditions. The results showed that SOT scores of HA users decreased significantly in the DT compared to the ST (p of Condition 1: < .001; p of Condition 4: < .001; p of Condition 6: = .001). HA users' SOT scores in the DT condition were statistically significantly lower than controls (p of Condition 1: < .003; p of Condition 4: < .009; p of Condition 6: = .004). This suggests that the presence of a visual cognitive additional task has a negative impact on balance performance in young adults with HAs. These findings highlight the importance of considering the impact of cognitive tasks on balance performance in young adults with HAs. Further studies should investigate the specific needs of hearing loss patients in multitasking conditions, including age, degree of hearing loss, and cognitive ability, to develop effective interventions to reduce the risk of falls.

Subclinical structural atypicality of retinal thickness and its association with gray matter volume in the visual cortex of maltreated children

Childhood maltreatment is reportedly associated with atypical gray matter structures in the primary visual cortex (V1). This study explores the hypothesis that retinal structures, the sensory organs of vision, are associated with brain atypicality and child maltreatment and examines their interrelation. General ophthalmologic examinations, visual cognitive tasks, retinal imaging, and structural magnetic resonance imaging (MRI) were conducted in children and adolescents aged 9–18 years with maltreatment experiences (CM) and typically developing (TD) children. The retinal nerve fiber layer (RNFL), the most superficial of the ten distinct retinal layers, was found to be significantly thinner in both eyes in CM. While whole-brain analysis using Voxel-based morphometry revealed a significantly larger gray matter volume (GMV) in the thalamus in CM, no significant correlation with RNFL thickness was observed. However, based on region-of-interest analysis, a thinner RNFL was associated with a larger GMV in the right V1. Although it cannot be ruled out that this outcome resulted from maltreatment alone, CM demonstrated subclinical structural atypicality in the retina, which may also correlate with the immaturity of V1 development. Examination of retinal thickness offers a novel clinical approach to capturing characteristics associated with childhood maltreatment.

Dissecting Bayes: Using influence measures to test normative use of probability density information derived from a sample.

Bayesian decision theory (BDT) is frequently used to model normative performance in perceptual, motor, and cognitive decision tasks where the possible outcomes of actions are associated with rewards or penalties. The resulting normative models specify how decision makers should encode and combine information about uncertainty and value-step by step-in order to maximize their expected reward. When prior, likelihood, and posterior are probabilities, the Bayesian computation requires only simple arithmetic operations: addition, etc. We focus on visual cognitive tasks where Bayesian computations are carried out not on probabilities but on (1) probability density functions and (2) these probability density functions are derived from samples. We break the BDT model into a series of computations and test human ability to carry out each of these computations in isolation. We test three necessary properties of normative use of pdf information derived from a sample-accuracy, additivity and influence. Influence measures allow us to assess how much weight each point in the sample is assigned in making decisions and allow us to compare normative use (weighting) of samples to actual, point by point. We find that human decision makers violate accuracy and additivity systematically but that the cost of failure in accuracy or additivity would be minor in common decision tasks. However, a comparison of measured influence for each sample point with normative influence measures demonstrates that the individual's use of sample information is markedly different from the predictions of BDT. We will show that the normative BDT model takes into account the geometric symmetries of the pdf while the human decision maker does not. An alternative model basing decisions on a single extreme sample point provided a better account for participants' data than the normative BDT model.

Phenotypic effect of GBA1 variants in individuals with and without Parkinson's disease: The RAPSODI study

BackgroundVariants in the GBA1 gene cause the lysosomal storage disorder Gaucher disease (GD). They are also risk factors for Parkinson's disease (PD), and modify the expression of the PD phenotype.The penetrance of GBA1 variants in PD is incomplete, and the ability to determine who among GBA1 variant carriers are at higher risk of developing PD, would represent an advantage for prognostic and trial design purposes. ObjectivesTo compare the motor and non-motor phenotype of GBA1 carriers and non-carriers. MethodsWe present the cross-sectional results of the baseline assessment from the RAPSODI study, an online assessment tool for PD patients and GBA1 variant carriers. The assessment includes clinically validated questionnaires, a tap-test, the University of Pennsyllvania Smell Identification Test and cognitive tests. Additional, homogeneous data from the PREDICT-PD cohort were included. ResultsA total of 379 participants completed all parts of the RAPSODI assessment (89 GBA1-negative controls, 169 GBA1-negative PD, 47 GBA1-positive PD, 47 non-affected GBA1 carriers, 27 GD). Eighty-six participants were recruited through PREDICT-PD (43 non-affected GBA1 carriers and 43 GBA1-negative controls). GBA1-positive PD patients showed worse performance in visual cognitive tasks and olfaction compared to GBA1-negative PD patients. No differences were detected between non-affected GBA1 carriers carriers and GBA1-negative controls. No phenotypic differences were observed between any of the non-PD groups. ConclusionsOur results support previous evidence that GBA1-positive PD has a specific phenotype with more severe non-motor symptoms. However, we did not reproduce previous findings of more frequent prodromal PD signs in non-affected GBA1 carriers.

14 Prevalence of Mid-Range Visual Functions and their Relationship to Higher-order Visual Functions after Stroke

Objective:Visual deficits are common after stroke and are powerful predictors for the chronic functional outcome. However, while basic visual field and recognition deficits are relatively easy to assess with standardized methods, selective deficits in visual primitives, such as shape or motion, are harder to identify, as they often require a symmetrical bilateral posterior lesion in order to provoke full field deficits. We aimed to investigate the prevalence and co-occurrence of hemifield “mid-range” visual deficits. In addition, we looked at the repercussions of these mid-range deficits on higher-order visual cognitive functions, such as visuoconstruction and memory. At a more theoretical level, we investigated whether associations between deficits in 'mid-range’ visual functions and deficits in higher-order visual cognitive functions are in line with a hierarchical, two-pathway model of the visual brain.Participants and Methods:In 220 stroke patients and a healthy control group (N=49), we assessed the perception of colour (isoluminant stimuli in the red-green range), shape (Efron shapes), location (dot in a circle), orientation (lines at different angles), contrast (bars with converging grey-level differences), texture (from Brodatz grayscale texture album) and correlated motion (different percentages of dots moving in the same direction). All tasks started with a fixation dot presented at the centre of the screen. After one second, a target stimulus was presented on the horizontal midline at either 5° to the left or at 5° to the right side of the fixation. Then, after 1.5 seconds, two response items appeared in addition to the target stimulus for three seconds. To control for eye movements, we used an eye-tracker to present the target in a gaze contingent fashion. Thus, the target always remained in the correct retinal position independent of eye movements. In a subset of 182 ischemic stroke patients, we also assessed visuoconstruction (Copy Rey-Complex Figure Test), visual emotion recognition (FEEST test) and visual memory (Doors-test).Results:The results showed that deficits in motion-perception were most prevalent (26%), followed by colour (22%), texture (22%), location (21%), orientation (18%), contrast (14%), shape (14%) and glossiness (13%). 63% of the stroke patients showed one or more mid-range visual deficits. Overlap of deficits was small; they mostly occurred in isolation or co-occurred with only one or two other deficits. Impairments in mid-range visual functions could not predict performance on higher-order visual cognitive tasks. Impaired visuoconstruction and visual memory were only modestly predicted by a worse location perception. Impaired emotion perception was modestly predicted by a worse orientation perception. In addition, double dissociations were found: there were patients with selective deficits in 'mid-range’ visual functions without higher-order visual deficits and vice versa.Conclusions:First, deficits in “mid-range” visual functions are very prevalent. Since we found no strong patterns of co-occurrences, we suggest that an assessment of deficits at this level of visual processing requires screening the full range of visual functions. Second, the relationship between mid-range visual tasks and higher-order visual cognitive tasks is weak. Finally, our findings are not supportive of the hierarchical, two-pathway model but more in line with an alternative patchwork model.

Association of Bilateral Vestibulopathy With and Without Hearing Loss With Cognitive-Motor Interference

The past years, evidence suggested that the primary symptoms traditionally associated with bilateral vestibulopathy (BV) do not represent the full picture of this patient population. Recent literature also demonstrated cognitive impairment. However, although multitasking and dual-tasking are widely present in everyday activities, most of these studies assessed cognitive function only in single-task conditions. To uncover the association of BV with and without hearing loss with cognitive and motor performance and cognitive-motor interference. This prospective case-control study assessed persons with an isolated BV and persons with BV and a concomitant hearing loss compared with a healthy control group. Data were analyzed in December 2022. The study was conducted at Ghent University (Ghent, Belgium). Data collection took place between March 26, 2021, and November 29, 2022. All participants completed the 2BALANCE dual-task protocol, comprising a static and a dynamic motor task that was combined with 5 visual cognitive tasks. These cognitive tasks assessed mental rotation, visuospatial memory, working memory, response inhibition (executive function), and processing speed. All cognitive tasks were performed in a single-task condition (while seated) and in a dual-task condition (combined with a static and a dynamic motor task). The static task comprised balancing on a force platform with foam pad, and the dynamic task comprised walking at a self-selected speed on the GAITRite Walkway. Both motor tasks were performed in the single-task and dual-task condition. Nineteen persons with BV and hearing loss (mean [SD] age, 56.70 [10.12] years; 10 women [52.6%]), 22 persons with an isolated BV (mean [SD] age, 53.66 [13.35] years; 7 women [31.8%]), and 28 healthy control participants were included (mean [SD] age, 53.73 [12.77] years; 12 women [42.9%]). Both patient groups had mental rotation and working memory impairment in a single-task condition and slower processing speed when walking (ie, during the dynamic dual-task condition). Additionally, the patient group with hearing loss had impaired visuospatial memory and executive function deficits in single-task and dual-task conditions, while this could only be elicited when performing a motor task in persons with isolated BV (ie, when dual-tasking). The findings of this case-control study suggest an association between vestibular function and cognitive and motor performance, even greater in persons with a concomitant hearing loss than in persons with an isolated BV.

How Resource Demands of Nondriving-Related Tasks and Engagement Time Affect Drivers’ Physiological Response and Takeover Performance in Conditional Automated Driving

Drivers are allowed to perform a nondriving-related task (NDRT) in the Level-3 (L3) automated driving, which inevitably promotes a variety of complex NDRTs. Hence, investigating the effect of NDRTs on drivers’ behavior is necessary to ensure a safe transition from automated to manual driving. The main aim of this study is to examine the effect of resource demands of NDRTs and its engagement time on drivers’ physiological responses, takeover performance, and subjective ratings. A total of 42 participants were recruited to conduct a driving simulator study. Results showed that visual and physical resource demands significantly increased participants’ response time and deteriorated their takeover quality. Engagement time significantly affected participants’ drowsiness and response time to the takeover request. In addition, participants rated the physical–visual–cognitive task as the most challenging task and the cognitive task as the least demanding task, which matches the takeover performance. Moreover, pupil diameter responds significantly to visual resource demands rather than physical resource demands. Physical resource demands had a significant tendency to elevate heart rate. This study suggested that tasks with a certain level of cognitive resource demand may be more appropriate for L3 automated driving. The findings of this study make it possible to use physiological responses to identify NDRT types or even predict drivers’ takeover performance in automated driving. Based on this, the time budget could be dynamically adjusted to ensure a safe transition.

Co-variations of cerebral blood volume and single neurons discharge during resting state and visual cognitive tasks in non-human primates

To better understand how the brain allows primates to perform various sets of tasks, the ability to simultaneously record neural activity at multiple spatiotemporal scales is challenging but necessary. However, the contribution of single-unit activities (SUAs) to neurovascular activity remains to be fully understood. Here, we combine functional ultrasound imaging of cerebral blood volume (CBV) and SUA recordings in visual and fronto-medial cortices of behaving macaques. We show that SUA provides a significant estimate of the neurovascular response below the typical fMRI spatial resolution of 2mm3. Furthermore, our results also show that SUAs and CBV activities are statistically uncorrelated during the resting state but correlate during tasks. These results have important implications for interpreting functional imaging findings while one constructs inferences of SUA during resting state or tasks.

Classification of Parkinson’s disease with dementia using phase locking factor of event-related oscillations to visual and auditory stimuli

Objective. In the last decades, machine learning approaches have been widely used to distinguish Parkinson’s disease (PD) and many other neuropsychiatric diseases. They also speed up the clinicians and facilitate decision-making for several conditions with similar clinical symptoms. The current study attempts to detect PD with dementia (PDD) by event-related oscillations (EROs) during cognitive processing in two modalities, i.e. auditory and visual. Approach. The study was conducted to discriminate PDD from healthy controls (HC) using event-related phase-locking factors in slow frequency ranges (delta and theta) during visual and auditory cognitive tasks. Seventeen PDD and nineteen HC were included in the study, and linear discriminant analysis was used as a classifier. During classification analysis, multiple settings were implemented by using different sets of channels (overall, fronto-central and temporo-parieto-occipital (TPO) region), frequency bands (delta-theta combined, delta, theta, and low theta), and time of interests (0.1–0.7 s, 0.1–0.5 s and 0.1–0.3 s for delta, delta-theta combined; 0.1–0.4 s for theta and low theta) for spatial-spectral-temporal searchlight procedure. Main results. The classification performance results of the current study revealed that if visual stimuli are applied to PDD, the delta and theta phase-locking factor over fronto-central region have a remarkable contribution to detecting the disease, whereas if auditory stimuli are applied, the phase-locking factor in low theta over TPO and in a wider range of frequency (1–7 Hz) over the fronto-central region classify HC and PDD with better performances. Significance. These findings show that the delta and theta phase-locking factor of EROs during visual and auditory stimuli has valuable contributions to detecting PDD.

Multifractal Nonlinearity Moderates Feedforward and Feedback Responses to Suprapostural Perturbations.

An adaptive response to unexpected perturbations requires near-term and long-term adjustments over time. We used multifractal analysis to test how nonlinear interactions across timescales might support an adaptive response following an unpredictable perturbation. We reanalyzed torque data from 44 young and 24 older adults who performed a single-leg squat task challenged by an unexpected mechanical perturbation and a secondary visual-cognitive task. We report three findings: (a) multifractal nonlinearity interacted with pre-perturbation torque production and task error to presage greater pre-voluntary feedforward increases and greater voluntary reductions, respectively, in post-perturbation task error; (b) multifractal nonlinearity presaged relatively smaller task error than standard deviations of both pre-perturbation torques and pre-perturbation task error; and (c) increased task demand (e.g., age-related changes in dexterity and dual-task settings) led to multifractal nonlinearity presaging reduced task error. All these results were consistent with our expectations, except that a pre-perturbation knee torque-dependent increase in post-perturbation task error appeared later for older than for younger participants. This correlational multifractal modeling offered theoretical clarity on the possible roles of nonlinear interactions across timescales, moderating both feedforward and feedback processes, and presaging greater stability when the standard deviation is relatively large and task demands are strong. Thus, multifractal nonlinearity usefully describes movement variability even when paired with classical descriptors like the standard deviation. We discuss potential insights from these findings for understanding suprapostural dexterity and developing rehabilitative interventions.

Perceptual decision-making in autism as assessed by “spot the difference” visual cognition tasks

Discriminating between similar figures proves to be a remarkably demanding task due to the limited capacity of our visual cognitive processes. Here we examine how perceptual inference and decision-making are modulated by differences arising from neurodiversity. A large sample of autistic (n = 140) and typical (n = 147) participants completed two forced choice similarity judgement tasks online. Each task consisted of “match” (identical figures) and “mismatch” (subtle differences between figures) conditions. Signal detection theory analyses indicated a response bias by the autism group during conditions of uncertainty. More specifically, autistic participants were more likely to choose the “mismatch” option, thus leading to more hits on the “mismatch” condition, but also more false alarms on the “match” condition. These results suggest differences in response strategies during perceptual decision-making in autism.

Mid-range visual functions in relation to higher-order visual functions after stroke

ABSTRACT Introduction We aimed to investigate whether associations between deficits in “mid-range” visual functions and deficits in higher-order visual cognitive functions in stroke patients are more in line with a hierarchical, two-pathway model of the visual brain, or with a patchwork model, which assumes a parallel organization with many processing routes and cross-talk. Methods A group of 182 ischemic stroke patients was assessed with a new diagnostic set-up for the investigation of a comprehensive range of visuosensory mid-range functions: color, shape, location, orientation, correlated motion, contrast and texture. With logistic regression analyses we investigated the predictive value of these mid-range functions for deficits in visuoconstruction (Copy of the Rey-Complex Figure Test), visual emotion recognition (Ekman 60 Faces Test of the FEEST) and visual memory (computerized Doors-test). Results Results showed that performance on most mid-range visual tasks could not predict performance on higher-order visual cognitive tasks. Correlations were low to weak. Impaired visuoconstruction and visual memory were only modestly predicted by a worse location perception. Impaired emotion perception was modestly predicted by a worse orientation perception. In addition, double dissociations were found: there were patients with selective deficits in mid-range visual functions without higher-order visual deficits and vice versa. Conclusions Our findings are not in line with the hierarchical, two-pathway model. Instead, the findings are more in line with alternative “patchwork” models, arguing for a parallel organization with many processing routes and cross-talk. However, future studies are needed to test these alternative models.

The OpenFeeder: A flexible automated RFID feeder to measure interspecies and intraspecies differences in cognitive and behavioural performance in wild birds

Abstract Understanding the ecology and evolution of personality and cognition requires the development of new tools to measure individual and species differences in behavioural and cognitive performances in wild populations. Furthermore, such tools should facilitate collection of large sample sizes, evaluate the repeatability of measured traits and allow direct comparison of species performances across a variety of behavioural tasks. Here we present a RFID‐based feeder (OpenFeeder) designed to run visual cognitive tasks in wild animals. We illustrate the flexibility of the tool showing performances of three wild passerine species (Parus major, Cyanistes caeruleus and Poecile palustris) in an associative learning task. We recorded performances of a large number of individuals (&gt;300) in the wild and showed both interspecific and intraspecific differences in associative learning. We also found moderate to high repeatability in individual differences in associative learning in each species. We show that the OpenFeeder is a flexible tool to record performance in multiple cognitive and behavioural tasks in free‐ranging animals across a variety of passerine species. The design, firmware and software are open source to facilitate use in a wide variety of species and thus allow continuous improvement of the system and development of new behavioural and cognitive tasks. In doing so, we hope that this tool will be used by a large community of cognitive ecologists and comparative psychologists for both within and across species studies. Furthermore, our system should facilitate replication of results across populations along large‐scale environmental gradients to improve our understanding of the role ecology plays in the evolution of cognitive traits.

Development and reliability of a visual-cognitive medial side hop for return to sport testing

ObjectivesTo develop and evaluate the reliability of a new visual-cognitive medial side hop (VCMH) test that challenges physical and cognitive performance to potentially improve return to sport testing. DesignTest-retest experimental design. SettingLaboratory. ParticipantsTwenty-two healthy college students participated (11 females; 23.5 ± 3.64 years; 172.9 ± 11.58 cm; 74.1 ± 17.25 kg; Tegner Score 5.6 ± 1.1). Main outcome measuresSubjects performed a medial side hop for distance with and without a visual-cognitive task (VCMH). Maximum hop distance and cognitive errors were measured. ResultsThere was strong reliability for the traditional medial side hop (ICC3,1 = 0.88[0.72, 0.95]; SEM = 7.16 cm) and VCMH distances (ICC3,1 = 0.86[0.66, 0.94]; SEM = 6.82 cm). Maximum hop distance was significantly lower during the VCMH (86.9 ± 18.2 cm) compared to the traditional medial side hop (96.3 ± 20.7 cm; p < 0.05; d = 0.74), with a performance deficit of 9.69%. ConclusionThe VCMH has high test-retest reliability and resulted in a significant dual-task cost with a reduction in physical performance when compared to the traditional medial side hop.

Investigation of the optimal time interval between task-irrelevant auditory probes for evaluating mental workload in the shortest possible time

Event-related brain potentials (ERPs) elicited by auditory stimuli unrelated to a current visual-cognitive task (i.e., task-irrelevant auditory probes) can be used to evaluate the level of mental workload. Towards the evaluation of workload in the shortest possible time, the present study with a multiple-stimulus paradigm (Takeda and Kimura, 2014, Int. J. Psychophysiol.) examined whether manipulating time intervals between probes could improve the temporal resolution in evaluating workload. Probes were presented in four interval conditions as a combination of two mean interval lengths [long (600 ms) vs. short (300 ms)] and two interval variabilities [variable (five levels) vs. fixed], while participants were performing a driving game at slow and fast speeds (i.e., imposing low and high workload, respectively). For each interval condition, the minimum data length required to obtain a significant difference in the amplitude of ERPs (i.e., auditory N1 and P2) between the slow and fast driving tasks was estimated. The N1 difference was significant in all four interval conditions but the required minimum data lengths to observe this difference did not greatly differ across the interval conditions (about 60–90 s). The P2 difference was significant only in the long-variable condition and the required minimum data length was about 120 s. These results suggest that, at least with a multiple-stimulus paradigm, manipulations of time intervals between probes did not greatly improve the temporal resolution in evaluating mental workload; at present, long-variable intervals would be optimal for evaluating mental workload in detail.

A Functional Near Infrared Spectroscopy Investigation of the Physiological Underpinnings of Visual Cognitive Workload After Concussion

Background:In concussion, functional near infrared spectroscopy (fNIRS) has been shown to detect differences in cortical oxygenation during neurocognitive testing, with concussed adults manifesting less task-based cortical activation compared to controls. In addition, fNIRS has identified significantly reduced interhemispheric coherence in adult concussions relative to controls. In addition, adults with greater post-concussive symptom burden demonstrate lower task-related oxygenation in the frontal and dorsolateral prefrontal cortex (DLPFC) and reduced connectivity compared to controls.Hypothesis:The goal of this study was to use fNIRS to identify any differences in visual task-related cortical activation between concussed adolescents and healthy controls while performing a the King-Devick (KD) test.Methods:We enrolled 112 adolescents, ages 12-18 years, with recent concussion and 165 healthy controls as part of a large observational prospective cohort. Participants were provided standardized instructions to read the KD cards while wearing the fNIRS sensor pad. The relative changes in the difference of oxy-and deoxy-hemoglobin concentrations over each task condition for each optode were calculated via the Modified Beer-Lambert Law using local baselines for each task condition period as its beginning. The averaged oxy-hemoglobin concentration changes for each task period were used for statistical analysis of group (e.g., concussed vs healthy) effect.Results:The concussed adolescents (n=112) and healthy controls (n=165) were demographically comparable with respect to age, sex, and race/ethnicity. The concussed group was more likely to have a history of prior concussion (p = <.0001) and migraine (p = .0001) compared to the healthy control group (Table 1). The concussed adolescents were assessed with fNIRS while performing a visual task a median of 10 days after injury (IQR 4-16). The concussed group had significantly lower oxygenation changes that are the difference between oxygenated and deoxygenated hemoglobin as an indicator of task-evoked response, on left lateral prefrontal area (p<.005, FDR q<.005). As expected, there was also a main effect for task condition (cards) at right lateral prefrontal cortex (p<.001, FDR q<.005).Conclusions:fNIRS is able to distinguish concussed adolescents from healthy controls while performing a visual-cognitive task, the K-D test. Injured adolescents with concussion demonstrated a compensatory pattern of cortical activation, suggesting localized brain dysfunction, recruiting from both hemispheres, distinguishing it from the pattern of cortical activation in healthy controls. fNIRS, as a modality, is not only able to differentiate concussion from healthy controls, but also captures the compensatory mechanisms of cortical activation that underlie visual cognitive function after injury.

Driver's Visual Attention Characteristics and Their Emotional Influencing Mechanism under Different Cognitive Tasks.

The visual attention system is the gateway to the human information processing system, and emotion is an important part of the human perceptual system. In this paper, the driver’s visual attention characteristics and the influences of typical driving emotions on those were explored through analyzing driver’s fixation time and identification accuracy to different visual cognitive tasks during driving. The results showed that: the increasing complexity of the cognitive object led to the improvement of visual identification speed. The memory and recall process increased drivers’ fixation time to cognitive objects, and the recall accuracy decreased with the increase in time interval. The increase in the number of cognitive objects resulted in the driver improving the visual identification speed for the cognitive object at the end of the sequence consciously. The results also showed that: the visual cognitive efficiency was improved in the emotional states of anger and contempt, and was decreased in the emotional states of surprise, fear, anxiety, helplessness and pleasure, and the emotional state of relief had no significant effect on the visual cognitive efficiency. The findings reveal the driver’s visual information processing mechanism to a certain extent, which are of great significance to understand the inner micro-psychology of driver’s cognition.

Investigating Classification Methods using Fixation Patterns to Predict Visual Tasks

Studies have shown the possibility to classify user tasks from eye-movement data. We present a new way to determine the optimal model for different visual cognitive tasks using data that includes two types of visual search tasks, a visual exploration task, a blank screen task, and a task where a user needs to fixate at the center of any scene. We used CNN and SVM models on RGB images generated from fixation scan paths from these tasks. We also used AdaBoost on filtered eye movement data as a baseline. Our study shows that deep learning gives the best accuracy for classifying between visual search tasks but misclassified between visual search and visual exploration tasks. Machine learning-based methods performed with high accuracy classifying tasks that involve minimal visual search. Our study gives insight on the best model to choose by type of visual task using eye movement data.