Modeling the role of fixational eye movements in real-world scenes

The concerted action of saccades and fixational eye movements are crucial for seeing stationary objects in the visual world. We studied how these eye movements contribute to retinal coding of visual information using the archer fish as a model system. We quantified the animal's ability to distinguish among objects of different sizes and measured its eye movements. We recorded from populations of retinal ganglion cells with a multielectrode array, while presenting visual stimuli matched to the behavioral task. We found that the beginning of fixation, namely the time immediately after the saccade, provided the most visual information about object size, with fixational eye movements, which consist of tremor and drift in the archer fish, yielding only a minor contribution. A simple decoder that combined information from ≤15 ganglion cells could account for the behavior. Our results support the view that saccades impose not just difficulties for the visual system, but also an opportunity for the retina to encode high quality “snapshots” of the environment.

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Microsaccades in applied environments: Real-world applications of fixational eye movement measurements

Journal of Eye Movement Research ◽

10.16910/jemr.12.6.15 ◽

2020 ◽

Vol 12 (6) ◽

Author(s):

Robert G Alexander ◽

Stephen L Macknik ◽

Susana Martinez-Conde

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Athletic Training ◽

Real World ◽

High Speed ◽

Sensory Deprivation ◽

Assessment Tools ◽

Current Evidence ◽

Fixational Eye Movements ◽

Real World Applications

Across a wide variety of research environments, the recording of microsaccades and other fixational eye movements has provided insight and solutions into practical problems. Here we review the literature on fixational eye movements—especially microsaccades—in applied and ecologically-valid scenarios. Recent technical advances allow noninvasive fixational eye movement recordings in real-world contexts, while observers perform a variety of tasks. Thus, fixational eye movement measures have been obtained in a host of real-world scenarios, such as in connection with driver fatigue, vestibular sensory deprivation in astronauts, and elite athletic training, among others. Here we present the state of the art in the practical applications of fixational eye movement research, examine its potential future uses, and discuss the benefits of including microsaccade measures in existing eye movement detection technologies. Current evidence supports the inclusion of fixational eye movement measures in real-world contexts, as part of the development of new or improved oculomotor assessment tools. The real-world applications of fixational eye movement measurements will only grow larger and wider as affordable high-speed and high-spatial resolution eye trackers become increasingly prevalent.

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Eye Movements in Drawing Simple Lines

Perception ◽

10.1068/p5544 ◽

2007 ◽

Vol 36 (8) ◽

pp. 1152-1167 ◽

Cited By ~ 20

Author(s):

John Tchalenko

Keyword(s):

Eye Movements ◽

Real World ◽

Movement Trajectory ◽

Stable Fixation ◽

End Point

As part of an investigation into real-world drawing, eye movements and eye – hand interactions have been recorded for twenty subjects of varying drawing experience drawing simple straight and curved lines and a square. Two modes of eye — hand behaviour were observed. In the first, named ‘close pursuit’, fixations closely followed the pencil with a sequence of small saccades. In the second, named ‘target locking’, a stable fixation was made on the end-point of the line throughout the entire drawing action. Depending on subject and type of line, close pursuit, target locking, or a combination of these modes was used regardless of previous drawing experience. The results are discussed in terms of the role of the eye in the control of the movement trajectory of the hand.

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IDENTIFYING TRENDS IN MICROSACCADE RATE ON OCULOMOTOR TRACKER IN EARLY VS LATE STAGE PEDIATRIC CASES WITH PERSISTENT POST-CONCUSSION SYMPTOMS (PPCS)

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121s00166 ◽

2021 ◽

Vol 9 (7_suppl3) ◽

pp. 2325967121S0016

Author(s):

Prem Kumar Thirunagari ◽

Nancy Phu ◽

David Tramutolo ◽

Hector Rieiro ◽

Tanya Polec ◽

...

Keyword(s):

Eye Movements ◽

Late Stage ◽

Visual Processing ◽

Pediatric Patients ◽

Early Stage ◽

Statistical Significance ◽

Small Sample ◽

T Test ◽

Fixational Eye Movements

Background: Oculomotor and visual processing deficits occur commonly after brain injury in young athletes. A subset of these concussed athletes do experience prolonged recoveries or PPCS with ongoing oculomotor deficits and visual symptoms. There have been limited studies conducted to determine the significance of oculomotor tracking (OMT) testing in the pediatric population, and even less investigating the role of microsaccades. Hence, investigations on microsaccades(MS), physiological adjustive micro eye movements critical in visual processing and central/peripheral visual integration, may provide insight on the role of visual dysfunction in PPCS course, prognosis, and management. Purpose: The purpose of this study is to identify possible MS rate trends and differences between early and late stage PPCS pediatric patients. Methods: A retrospective cohort study of 41 pediatric patients with PPCS or symptoms greater than one month from injury. Data was collected from 7/1/2018 to 12/1/2019 and the age group ranged from 8 to 21 years. For each participant, using the OMT device we measured the number of saccades generated, the size and speed of the microsaccades, the area covered and the ratio of vertical-to-horizontal direction component of the fixational eye movements, using a 250 Hz video-eye tracker mounted inside a HTC Vive VR headset. Participants were instructed to fixate on a central dot for 140 seconds, in 20-second intervals. Patients were classified into early or late stages of PPCS (early stage: 1-6 months; late stage: >6 months) to compare MS rate between stages. Exclusion criteria included history of visual disorders, learning disorders, seizure disorder, or intracranial hemorrhage. Results: 27 patients were in the early stage while 14 patients were in the late stage. The early stage group had a mean MS rate of 125 beats/min while the late stage group had a mean MS rate of 116 beats/min. A two sample t-test assuming no difference between early and late stage patients resulted in a p value of 0.51. Conclusion: There is a potential trend in declining MS numbers with progressive PPCS stage. Although the t-test didn’t show statistical significance, this could be due to the small sample size of our study. Future studies are needed to validate this initial finding and to identify the significance of microsaccade patterns in concussion prognosis and management. [Figure: see text]

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Beyond Fixation: detailed characterization of neural selectivity in free-viewing primates

10.1101/2021.11.06.467566 ◽

2021 ◽

Author(s):

Jacob L Yates ◽

Shanna H Coop ◽

Gabriel H Sarch ◽

Ruei-Jr Wu ◽

Daniel A Butts ◽

...

Keyword(s):

Eye Movements ◽

Receptive Fields ◽

Natural Behavior ◽

Visual Neurons ◽

Trained Subjects ◽

V1 Neurons ◽

Fixational Eye Movements ◽

Neural Selectivity

Virtually all vision studies use a fixation point to stabilize gaze, rendering stimuli on video screens fixed to retinal coordinates. This approach requires trained subjects, is limited by the accuracy of fixational eye movements, and ignores the role of eye movements in shaping visual input. To overcome these limitations, we developed a suite of hardware and software tools to study vision during natural behavior in untrained subjects. We show this approach recovers receptive fields and tuning properties of visual neurons from multiple cortical areas of marmoset monkeys. Combined with high-precision eye-tracking, it achieves sufficient resolution to recover the receptive fields of foveal V1 neurons. These findings demonstrate the power of this approach for characterizing neural response while simultaneously studying the dynamics of natural behavior.

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Contextual guidance of eye movements and attention in real-world scenes: The role of global features in object search.

Psychological Review ◽

10.1037/0033-295x.113.4.766 ◽

2006 ◽

Vol 113 (4) ◽

pp. 766-786 ◽

Cited By ~ 880

Author(s):

Antonio Torralba ◽

Aude Oliva ◽

Monica S. Castelhano ◽

John M. Henderson

Keyword(s):

Eye Movements ◽

Real World ◽

Global Features ◽

Object Search

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The Role of Symmetry in the Aesthetics of Residential Building Façades Using Cognitive Science Methods

Symmetry ◽

10.3390/sym12091438 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1438

Author(s):

Hamidreza Azemati ◽

Fatemeh Jam ◽

Modjtaba Ghorbani ◽

Matthias Dehmer ◽

Reza Ebrahimpour ◽

...

Keyword(s):

Eye Movements ◽

Mirror Symmetry ◽

Aesthetic Experience ◽

Residential Building ◽

Science Methods ◽

Fixational Eye Movements ◽

Significant Difference ◽

Building Facades ◽

The Aesthetic

Symmetry is an important visual feature for humans and its application in architecture is completely evident. This paper aims to investigate the role of symmetry in the aesthetics judgment of residential building façades and study the pattern of eye movement based on the expertise of subjects in architecture. In order to implement this in the present paper, we have created images in two categories: symmetrical and asymmetrical façade images. The experiment design allows us to investigate the preference of subjects and their reaction time to decide about presented images as well as record their eye movements. It was inferred that the aesthetic experience of a building façade is influenced by the expertise of the subjects. There is a significant difference between experts and non-experts in all conditions, and symmetrical façades are in line with the taste of non-expert subjects. Moreover, the patterns of fixational eye movements indicate that the horizontal or vertical symmetry (mirror symmetry) has a profound influence on the observer’s attention, but there is a difference in the points watched and their fixation duration. Thus, although symmetry may attract the same attention during eye movements on façade images, it does not necessarily lead to the same preference between the expert and non-expert groups.

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