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Psychological Review Jun 2024Research on saccadic and pursuit eye movements led to great advances in our understanding of sensorimotor processing and human behavior. However, studies often have...
Research on saccadic and pursuit eye movements led to great advances in our understanding of sensorimotor processing and human behavior. However, studies often have focused on isolated saccadic and pursuit eye movements measured with respect to different sensory information (static vs. dynamic targets). Here, we leveraged interindividual differences across a carefully balanced combination of different tasks to demonstrate that critical links in the control of oculomotor behavior were previously missed. We observed correlations in eye movement behavior across tasks, but only when compared with the same sensory information (e.g., pursuit gain and accuracy of saccades to moving targets). Within the same task, the coordination of saccadic and pursuit eye movements was tailored to the strengths of the individual: observers with more accurate saccades to moving targets rely on them more to catch up with moving targets. Our results have profound implications for the theoretical understanding of sensorimotor processing for oculomotor control. They necessitate a reevaluation of previous data used to map brain circuits for saccadic and pursuit eye movements measured with different types of relevant sensory information. Additionally, they underscore the importance of moving beyond average observations to embrace individual differences as a rich source of information. These individual differences not only reveal the strengths and weaknesses of observers. When combined across different tasks, they allow insights about why observers behave differently in a given task. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
PubMed: 38869856
DOI: 10.1037/rev0000477 -
Journal of Vision Jun 2024Microsaccades-tiny fixational eye movements-improve discriminability in high-acuity tasks in the foveola. To investigate whether they help compensate for low...
Microsaccades-tiny fixational eye movements-improve discriminability in high-acuity tasks in the foveola. To investigate whether they help compensate for low discriminability at the perifovea, we examined microsaccade characteristics relative to the adult visual performance field, which is characterized by two perceptual asymmetries: horizontal-vertical anisotropy (better discrimination along the horizontal than vertical meridian) and vertical meridian asymmetry (better discrimination along the lower than upper vertical meridian). We investigated whether and to what extent microsaccade directionality varies when stimuli are at isoeccentric locations along the cardinals under conditions of heterogeneous discriminability (Experiment 1) and homogeneous discriminability, equated by adjusting stimulus contrast (Experiment 2). Participants performed a two-alternative forced-choice orientation discrimination task. In both experiments, performance was better on trials without microsaccades between ready signal onset and stimulus offset than on trials with microsaccades. Across the trial sequence, the microsaccade rate and directional pattern were similar across locations. Our results indicate that microsaccades were similar regardless of stimulus discriminability and target location, except during the response period-once the stimuli were no longer present and target location no longer uncertain-when microsaccades were biased toward the target location. Thus, this study reveals that microsaccades do not flexibly adapt as a function of varying discriminability in a basic visual task around the visual field.
Topics: Humans; Saccades; Visual Fields; Male; Adult; Female; Young Adult; Photic Stimulation; Fixation, Ocular; Orientation; Discrimination, Psychological; Fovea Centralis
PubMed: 38869372
DOI: 10.1167/jov.24.6.11 -
Noro Psikiyatri Arsivi 2024Deceleration of vertical saccades, an early and characteristic finding of Niemann-Pick Type C (NP-C), may help diagnosis. Our aim in this study was to demonstrate the...
INTRODUCTION
Deceleration of vertical saccades, an early and characteristic finding of Niemann-Pick Type C (NP-C), may help diagnosis. Our aim in this study was to demonstrate the role of video-oculography (VOG), in the differential diagnosis of ataxia syndromes, particularly of NP-C, using this technique in the evaluation of saccadic velocity and smooth pursuit gain of ataxia patients.
METHODS
We recruited consecutive 50 ataxia patients and 50 healthy control subjects who were age and sex-matched with the patient group. Saccadic eye movements and smooth pursuit eye movements for different angles and different directions from patients and healthy subjects were recorded by using VOG.
RESULTS
Saccadic eye movement velocity and smooth pursuit gain values of the patients were significantly lower in all directions and at all angles as compared to healthy subjects. In the patient group, 3 cases out of 50 were selected as suspected NP-C, based on the dissociation between their markedly impaired vertical saccadic velocity and near normal to slightly impaired horizontal one and relatively intact smooth pursuit eye movements; the diagnoses in all 3 cases were confirmed with positive genetic testing, and thereupon Miglustat treatment was started.
CONCLUSION
Our findings support that cerebellar pathology in degenerative ataxia patients is associated with both impaired saccadic velocity and smooth pursuit gain, whereas in NP-C, only the impaired vertical saccades as opposed to relatively preserved other eye movements are seemingly a diagnostic marker for the entity. We conclude that recording of eye movements could be useful for differential diagnosis and monitorization of the treatment of ataxia syndromes as an easy and objective method.
PubMed: 38868844
DOI: 10.29399/npa.28563 -
Journal of Pathology Informatics Dec 2024Eye tracking has been used for decades in attempt to understand the cognitive processes of individuals. From memory access to problem-solving to decision-making, such... (Review)
Review
Eye tracking has been used for decades in attempt to understand the cognitive processes of individuals. From memory access to problem-solving to decision-making, such insight has the potential to improve workflows and the education of students to become experts in relevant fields. Until recently, the traditional use of microscopes in pathology made eye tracking exceptionally difficult. However, the digital revolution of pathology from conventional microscopes to digital whole slide images allows for new research to be conducted and information to be learned with regards to pathologist visual search patterns and learning experiences. This has the promise to make pathology education more efficient and engaging, ultimately creating stronger and more proficient generations of pathologists to come. The goal of this review on eye tracking in pathology is to characterize and compare the visual search patterns of pathologists. The PubMed and Web of Science databases were searched using 'pathology' AND 'eye tracking' synonyms. A total of 22 relevant full-text articles published up to and including 2023 were identified and included in this review. Thematic analysis was conducted to organize each study into one or more of the 10 themes identified to characterize the visual search patterns of pathologists: (1) effect of experience, (2) fixations, (3) zooming, (4) panning, (5) saccades, (6) pupil diameter, (7) interpretation time, (8) strategies, (9) machine learning, and (10) education. Expert pathologists were found to have higher diagnostic accuracy, fewer fixations, and shorter interpretation times than pathologists with less experience. Further, literature on eye tracking in pathology indicates that there are several visual strategies for diagnostic interpretation of digital pathology images, but no evidence of a superior strategy exists. The educational implications of eye tracking in pathology have also been explored but the effect of teaching novices how to search as an expert remains unclear. In this article, the main challenges and prospects of eye tracking in pathology are briefly discussed along with their implications to the field.
PubMed: 38868488
DOI: 10.1016/j.jpi.2024.100383 -
Journal of Neurophysiology Jun 2024Saccade adaptation plays a crucial role in maintaining saccade accuracy. The behavioral characteristics and neural mechanisms of saccade adaptation for an externally...
Saccade adaptation plays a crucial role in maintaining saccade accuracy. The behavioral characteristics and neural mechanisms of saccade adaptation for an externally cued movement, such as visually-guided saccades (VGS), are well studied in non-human primates. In contrast, little is known about the saccade adaptation of an internally driven movement, such as memory-guided saccades (MGS), which are guided by visuospatial working memory. As the oculomotor plant changes due to growth, aging, or skeletomuscular problems, both types of saccades need to be adapted. Do both saccade types engage a common adaptation mechanism? In this study, we compared the characteristics of amplitude decrease adaptation in MGS with VGS in non-human primates. We found that the adaptation speed was faster for MGS than for VGS. Saccade duration changed during MGS adaptation, while saccade peak velocity changed during VGS adaptation. We also compared the adaptation field, that is, the gain change for saccade amplitudes other than the adapted. The gain change for MGS declines on both smaller and larger sides of adapted amplitude, more rapidly for larger than smaller amplitudes, while the decline in VGS was reversed. Thus, the differences between VGS and MGS adaptation characteristics support the previously suggested hypothesis that the adaptation mechanisms of VGS and MGS are distinct. Furthermore, the result suggests that the MGS adaptation site is a brain structure that influences saccade duration, while the VGS adaptation site influences saccade peak velocity. These results should be beneficial for future neurophysiological experiments.
PubMed: 38865580
DOI: 10.1152/jn.00050.2024 -
Perception Jun 2024We used a simple stimulus, dissociating perceptually relevant information in space, to differentiate between bottom-up and task-driven fixations. Six participants viewed...
We used a simple stimulus, dissociating perceptually relevant information in space, to differentiate between bottom-up and task-driven fixations. Six participants viewed a dynamic scene showing the reaction of an elastic object fixed to the ceiling being hit. In one condition they had to judge the object's stiffness and in the other condition its lightness. The results show that initial fixations tend to land in the centre of an object, independent of the task. After the initial fixation, participants tended to look at task diagnostic regions. This fixation behaviour correlates with high perceptual performance. Similarly, low-latency saccades lead to fixations that do not depend on the task, whereas higher latency does.
PubMed: 38863405
DOI: 10.1177/03010066241253816 -
Traffic Injury Prevention Jun 2024Vehicle automation technologies have the potential to address the mobility needs of older adults. However, age-related cognitive declines may pose new challenges for...
OBJECTIVE
Vehicle automation technologies have the potential to address the mobility needs of older adults. However, age-related cognitive declines may pose new challenges for older drivers when they are required to take back or "takeover" control of their automated vehicle. This study aims to explore the impact of age on takeover performance under partially automated driving conditions and the interaction effect between age and voluntary non-driving-related tasks (NDRTs) on takeover performance.
METHOD
A total of 42 older drivers ( = 65.5 years, SD = 4.4) and 40 younger drivers ( = 37.2 years, SD = 4.5) participated in this mixed-design driving simulation experiment (between subjects: age [older drivers vs. younger drivers] and NDRT engagement [road monitoring vs. voluntary NDRTs]; within subjects: hazardous event occurrence time [7.5th min vs. 38.5th min]).
RESULTS
Older drivers exhibited poorer visual exploration performance (i.e., longer fixation point duration and smaller saccade amplitude), lower use of advanced driving assistance systems (ADAS; e.g., lower percentage of time adaptive cruise control activated [ACCA]) and poorer takeover performance (e.g., longer takeover time, larger maximum resulting acceleration, and larger standard deviation of lane position) compared to younger drivers. Furthermore, older drivers were less likely to experience driving drowsiness (e.g., lower percentage of time the eyes are fully closed and Karolinska Sleepiness Scale levels); however, this advantage did not compensate for the differences in takeover performance with younger drivers. Older drivers had lower NDRT engagement (i.e., lower percentage of fixation time on NDRTs), and NDRTs did not significantly affect their drowsiness but impaired takeover performance (e.g., higher collision rate, longer takeover time, and larger maximum resulting acceleration).
CONCLUSIONS
These findings indicate the necessity of addressing the impaired takeover performance due to cognitive decline in older drivers and discourage them from engaging in inappropriate NDRTs, thereby reducing their crash risk during automated driving.
PubMed: 38860883
DOI: 10.1080/15389588.2024.2352788 -
Eye (London, England) Jun 2024Multiple Sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system (CNS) characterized by inflammation, demyelination, and axonal... (Review)
Review
Multiple Sclerosis (MS) is a chronic autoimmune demyelinating disease of the central nervous system (CNS) characterized by inflammation, demyelination, and axonal damage. Early recognition and treatment are important for preventing or minimizing the long-term effects of the disease. Current gold standard modalities of diagnosis (e.g., CSF and MRI) are invasive and expensive in nature, warranting alternative methods of detection and screening. Oculomics, the interdisciplinary combination of ophthalmology, genetics, and bioinformatics to study the molecular basis of eye diseases, has seen rapid development through various technologies that detect structural, functional, and visual changes in the eye. Ophthalmic biomarkers (e.g., tear composition, retinal nerve fibre layer thickness, saccadic eye movements) are emerging as promising tools for evaluating MS progression. The eye's structural and embryological similarity to the brain makes it a potentially suitable assessment of neurological and microvascular changes in CNS. In the advent of more powerful machine learning algorithms, oculomics screening modalities such as optical coherence tomography (OCT), eye tracking, and protein analysis become more effective tools aiding in MS diagnosis. Artificial intelligence can analyse larger and more diverse data sets to potentially discover new parameters of pathology for efficiently diagnosing MS before symptom onset. While there is no known cure for MS, the integration of oculomics with current modalities of diagnosis creates a promising future for developing more sensitive, non-invasive, and cost-effective approaches to MS detection and diagnosis.
PubMed: 38858520
DOI: 10.1038/s41433-024-03132-y -
Translational Psychiatry Jun 2024This research aimed to devise and assess a mobile game therapy software for children with Attention-Deficit/Hyperactivity Disorder (ADHD), as well as evaluating its...
This research aimed to devise and assess a mobile game therapy software for children with Attention-Deficit/Hyperactivity Disorder (ADHD), as well as evaluating its suitability and effectiveness in improving the cognitive ability of typically developing children. The study encompassed 55 children diagnosed with ADHD and 55 neurotypical children. Initial assessments involved ADHD-related scales, computerized tests for information processing, and physiological-psychological evaluations. After a 4-week home-based game intervention, participants underwent re-evaluation using baseline measures and provided feedback on treatment satisfaction. Considering the small proportion of study participants who dropped out, data was analyzed using both the Intention-to-Treat (ITT) analysis and the Per-protocol (PP) analysis. The trial was registered at ClinicalTrials.gov (NCT06181747). In ITT analysis, post-intervention analysis using linear mixed models indicated that the ADHD group improved significantly more than the neurotypical group particularly in Continuous Performance Test (CPT) accuracy (B = -23.92, p < 0.001) and reaction time (B = 86.08, p < 0.01), along with enhancements in anti-saccade (B = -10.65, p < 0.05) and delayed-saccade tasks (B = 0.34, p < 0.05). A reduction in parent-rated SNAP-IV scores was also observed (B = 0.43, p < 0.01). In PP analysis, paired-sample t-tests suggested that the ADHD group had significant changes pre- and post-intervention, in terms of CPT Accuracy (t = -7.62, p < 0.01), Anti-saccade task Correct Rate (t = -3.90, p < 0.01) and SNAP-IV scores (t = -4,64, p < 0.01). However, no significant changes post-intervention were observed in the neurotypical group. Survey feedback highlighted a strong interest in the games across both groups, though ADHD participants found the game more challenging. Parents of ADHD children reported perceived benefits and a willingness to continue the game therapy, unlike the neurotypical group's parents. The findings advocated for the integration of serious video games as a complementary tool in ADHD treatment strategies, demonstrating the potential to augment attentional abilities and alleviate clinical symptoms. However, a randomized controlled trial (RCT) is needed to further verify its efficacy.
Topics: Humans; Attention Deficit Disorder with Hyperactivity; Child; Male; Female; Video Games; Feasibility Studies; Mobile Applications; Treatment Outcome
PubMed: 38858375
DOI: 10.1038/s41398-024-02964-2 -
Journal of Vision Jun 2024When interacting with the environment, humans typically shift their gaze to where information is to be found that is useful for the upcoming action. With increasing age,...
When interacting with the environment, humans typically shift their gaze to where information is to be found that is useful for the upcoming action. With increasing age, people become slower both in processing sensory information and in performing their movements. One way to compensate for this slowing down could be to rely more on predictive strategies. To examine whether we could find evidence for this, we asked younger (19-29 years) and older (55-72 years) healthy adults to perform a reaching task wherein they hit a visual target that appeared at one of two possible locations. In separate blocks of trials, the target could appear always at the same location (predictable), mainly at one of the locations (biased), or at either location randomly (unpredictable). As one might expect, saccades toward predictable targets had shorter latencies than those toward less predictable targets, irrespective of age. Older adults took longer to initiate saccades toward the target location than younger adults, even when the likely target location could be deduced. Thus we found no evidence of them relying more on predictive gaze. Moreover, both younger and older participants performed more saccades when the target location was less predictable, but again no age-related differences were found. Thus we found no tendency for older adults to rely more on prediction.
Topics: Humans; Aged; Middle Aged; Adult; Male; Female; Saccades; Aging; Young Adult; Fixation, Ocular; Reaction Time; Photic Stimulation; Psychomotor Performance; Eye Movements; Age Factors
PubMed: 38856982
DOI: 10.1167/jov.24.6.8