Is the eye-movement field confused about fixations and saccades? A survey among 124 researchers

Eye movements have been extensively studied in a wide range of research fields. While new methods such as mobile eye tracking and eye tracking in virtual/augmented realities are emerging quickly, the eye-movement terminology has scarcely been revised. We assert that this may cause confusion about two of the main concepts: fixations and saccades. In this study, we assessed the definitions of fixations and saccades held in the eye-movement field, by surveying 124 eye-movement researchers. These eye-movement researchers held a variety of definitions of fixations and saccades, of which the breadth seems even wider than what is reported in the literature. Moreover, these definitions did not seem to be related to researcher background or experience. We urge researchers to make their definitions more explicit by specifying all the relevant components of the eye movement under investigation: (i) the oculomotor component: e.g. whether the eye moves slow or fast; (ii) the functional component: what purposes does the eye movement (or lack thereof) serve; (iii) the coordinate system used: relative to what does the eye move; (iv) the computational definition: how is the event represented in the eye-tracker signal. This should enable eye-movement researchers from different fields to have a discussion without misunderstandings.

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A Fast and Effective System for Analysis of Optokinetic Waveforms with a Low-Cost Eye Tracking Device

Healthcare ◽

10.3390/healthcare9010010 ◽

2020 ◽

Vol 9 (1) ◽

pp. 10

Author(s):

Chong-Bin Tsai ◽

Wei-Yu Hung ◽

Wei-Yen Hsu

Keyword(s):

Eye Movements ◽

Eye Tracking ◽

Eye Movement ◽

Low Cost ◽

Saccadic Eye Movements ◽

Slow Phase ◽

Eye Tracker ◽

Effective System ◽

Tracking Device ◽

Traditional Approaches

Optokinetic nystagmus (OKN) is an involuntary eye movement induced by motion of a large proportion of the visual field. It consists of a “slow phase (SP)” with eye movements in the same direction as the movement of the pattern and a “fast phase (FP)” with saccadic eye movements in the opposite direction. Study of OKN can reveal valuable information in ophthalmology, neurology and psychology. However, the current commercially available high-resolution and research-grade eye tracker is usually expensive. Methods & Results: We developed a novel fast and effective system combined with a low-cost eye tracking device to accurately quantitatively measure OKN eye movement. Conclusions: The experimental results indicate that the proposed method achieves fast and promising results in comparisons with several traditional approaches.

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The Potential of Using an Eye Tracker in Architectural Education: Three Perspectives for Ordinary Users, Students and Lecturers

Buildings ◽

10.3390/buildings11060245 ◽

2021 ◽

Vol 11 (6) ◽

pp. 245

Author(s):

Marta Alina Rusnak ◽

Mateusz Rabiega

Keyword(s):

Eye Tracking ◽

Eye Movement ◽

Teaching Methods ◽

Architectural Education ◽

Eye Tracker ◽

Professional Skills ◽

Wide Range ◽

Professional Perception

The aim of this paper is to discuss the potential of eye trackers as tools providing diversified support for the architectural education of future designers. The possibility to track eye movement guaranteed by this group of devices enables an extension of knowledge on the non-professional perception of architectural creations. It also allows people to monitor progress while learning and verify a project’s assumptions as well as provide lecturers with an opportunity to optimize didactic methods. The paper includes authors’ ideas for modifications of teaching methods applied at technical universities. It is a result of an analysis of research related to the perception of urban designs and architectural objects—research during which noticeable differences were observed between how experts and non-professionals perceive these structures. What also contributed to the contents of this paper was a comprehension of the wide range of eye tracking studies examining the level of acquisition of specialist professional skills. The presented ideas are also based on the analysis and adaptation of eye-tracking research conducted by scientists within other areas of life.

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Eye-tracking-aided characterization of saccades and antisaccades in SYNE1 ataxia patients: a pilot study

BMC Neuroscience ◽

10.1186/s12868-021-00612-9 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Laszlo Szpisjak ◽

Gabor Szaraz ◽

Andras Salamon ◽

Viola L. Nemeth ◽

Noemi Szepfalusi ◽

...

Keyword(s):

Working Memory ◽

Eye Tracking ◽

Eye Movement ◽

Friedreich Ataxia ◽

Inverse Correlation ◽

Compound Heterozygous ◽

Healthy Controls ◽

Eye Tracker ◽

Wide Range ◽

Characteristic Features

Abstract Background SYNE1 ataxia is an autosomal recessive hereditary condition, the main characteristic features of which are gait and limb ataxia and cerebellar dysarthria. Reports have revealed that the clinical phenotype of SYNE1 ataxia is more complex than the first published cases with pure cerebellar signs indicated. The aim of this study was to characterize eye movement alterations in the first diagnosed Hungarian SYNE1 ataxia patients. Results Saccades and antisaccades were examined with an eye tracker device in 3 SYNE1 (one patient has two frameshift mutations [c.8515_8516insA, p.Met2839Asnfs*53 and c.11594_11595insG, p.Glu3866*] in a compound heterozygous state, whereas two subjects have a splicing variant [c.23146-2A > G] in a homozygous state), 6 Friedreich ataxia (FA) patients and 12 healthy controls. Besides that, detailed clinical phenotyping and comprehensive neuropsychological assessment were carried out in all patients with ataxia. In addition to the characteristic cerebellar alterations, pyramidal signs and polyneuropathy were observed at least in 2 SYNE1 ataxia patients, for which no other underlying reason was found. The eye tracking assessment revealed hypometric saccades in the longer amplitude (18.4°) saccadic paradigm in all SYNE1 patients, whereas 2 out of 3 SYNE1 subjects performed slow saccades as well. In the antisaccade task, higher incorrect ratios of antisaccades were demonstrated in SYNE1 patients compared to healthy controls, showing inverse correlation with working memory test results. The corresponding data of FA patients was dispersed over a wide range, partially overlapping with control data. Conclusions The current study draws attention to the presence of eye movement disorders in patients with SYNE1 ataxia and demonstrates that alterations in the antisaccade paradigm may be related to working memory deficits.

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Eye-tracking-aided Characterization of Saccades and Antisaccades in SYNE1 Ataxia Patients – A Pilot Study

10.21203/rs.3.rs-79409/v1 ◽

2020 ◽

Author(s):

Laszlo Szpisjak ◽

Gabor Szaraz ◽

Andras Salamon ◽

Viola L. Nemeth ◽

Noemi Szepfalusi ◽

...

Keyword(s):

Working Memory ◽

Eye Tracking ◽

Eye Movement ◽

Friedreich Ataxia ◽

Inverse Correlation ◽

Compound Heterozygous ◽

Healthy Controls ◽

Eye Tracker ◽

Wide Range ◽

Characteristic Features

Abstract BackgroundSYNE1 ataxia is an autosomal recessive hereditary condition, the main characteristic features of which are gait and limb ataxia and cerebellar dysarthria. Previous reports revealed that the clinical phenotype of SYNE1 ataxia is more complex than the first published cases with pure cerebellar signs. The aim of this study was to characterize the eye movement alterations of the first diagnosed Hungarian SYNE1 ataxia patients.ResultsSaccades and antisaccades were examined with eye tracker device in 3 SYNE1 (one patient has two frameshift mutations [c.8515_8516insA, p.Met2839Asnfs*53 and c.11594_11595insG, p.Glu3866*] in compound heterozygous state, whereas two subjects have a splicing variant [c.23146-2A>G] in homozygous state), 6 Friedreich ataxia (FA) patients and 12 healthy controls. Besides that, detailed clinical phenotyping and comprehensive neuropsychological assessment were implemented as well in all patients with ataxia.In addition to the characteristic cerebellar alterations, pyramidal signs and polyneuropathy were observed at least in 2 SYNE1 ataxia patients without any other underlying reason. The eye tracking assessment revealed hypometric saccades in the longer amplitude (18.4°) saccadic paradigm in all SYNE1 patients, whereas 2 out of 3 SYNE1 subjects performed slow saccades as well. In the antisaccade task, higher incorrect ratio of antisaccades were demonstrated in SYNE1 patients compared to healthy controls, showing inverse correlation with working memory test results. The corresponding data of FA patients dispersed in a wide range partially overlapping with control data.ConclusionsThe current study draws attention to the presence of eye movement disorders in patients with SYNE1 ataxia and demonstrates that alterations in the antisaccade paradigm may be related to working memory deficits.

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Human-level saccade detection performance using deep neural networks

Journal of Neurophysiology ◽

10.1152/jn.00601.2018 ◽

2019 ◽

Vol 121 (2) ◽

pp. 646-661 ◽

Cited By ~ 19

Author(s):

Marie E. Bellet ◽

Joachim Bellet ◽

Hendrikje Nienborg ◽

Ziad M. Hafed ◽

Philipp Berens

Keyword(s):

Neural Network ◽

Eye Movements ◽

Convolutional Neural Network ◽

Eye Movement ◽

Visual Processing ◽

Performance Metrics ◽

Visual Space ◽

Eye Tracker ◽

Wide Range ◽

Training Examples

Saccades are ballistic eye movements that rapidly shift gaze from one location of visual space to another. Detecting saccades in eye movement recordings is important not only for studying the neural mechanisms underlying sensory, motor, and cognitive processes, but also as a clinical and diagnostic tool. However, automatically detecting saccades can be difficult, particularly when such saccades are generated in coordination with other tracking eye movements, like smooth pursuits, or when the saccade amplitude is close to eye tracker noise levels, like with microsaccades. In such cases, labeling by human experts is required, but this is a tedious task prone to variability and error. We developed a convolutional neural network to automatically detect saccades at human-level accuracy and with minimal training examples. Our algorithm surpasses state of the art according to common performance metrics and could facilitate studies of neurophysiological processes underlying saccade generation and visual processing. NEW & NOTEWORTHY Detecting saccades in eye movement recordings can be a difficult task, but it is a necessary first step in many applications. We present a convolutional neural network that can automatically identify saccades with human-level accuracy and with minimal training examples. We show that our algorithm performs better than other available algorithms, by comparing performance on a wide range of data sets. We offer an open-source implementation of the algorithm as well as a web service.

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Fixation Duration and Pupil Size as Diagnostic Tools in Parkinson’s Disease

Journal of Parkinson s Disease ◽

10.3233/jpd-202427 ◽

2021 ◽

pp. 1-11

Author(s):

Panagiota Tsitsi ◽

Mattias Nilsson Benfatto ◽

Gustaf Öqvist Seimyr ◽

Olof Larsson ◽

Prof Per Svenningsson ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Eye Movements ◽

Eye Tracking ◽

Eye Movement ◽

Pupil Size ◽

Clinical Investigation ◽

Sampling Rate ◽

Diagnostic Tools ◽

Eye Tracker

Background: Visual and oculomotor problems are very common in Parkinson’s disease (PD) and by using eye-tracking such problems could be characterized in more detail. However, eye-tracking is not part of the routine clinical investigation of parkinsonism. Objective: To evaluate gaze stability and pupil size in stable light conditions, as well as eye movements during sustained fixation in a population of PD patients and healthy controls (HC). Methods: In total, 50 PD patients (66% males) with unilateral to mild-to-moderate disease (Hoehn & Yahr 1– 3, Schwab and England 70– 90% ) and 43 HC (37% males) were included in the study. Eye movements were recorded with Tobii Pro Spectrum, a screen-based eye tracker with a sampling rate of 1200 Hz. Logistic regression analysis was applied to investigate the strength of association of eye-movement measures with diagnosis. Results: Median pupil size (OR 0.811; 95% CI 0.666– 0.987; p = 0.037) and longest fixation period (OR 0.798; 95% CI 0.691-0.921; p = 0.002), were the eye-movement parameters that were independently associated with diagnosis, after adjustment for sex (OR 4.35; 95% CI 1.516– 12.483; p = 0.006) and visuospatial/executive score in Montreal Cognitive Assessment (OR 0.422; 95% CI 0.233– 0.764; p = 0.004). The area under the ROC curve was determined to 0.817; 95% (CI) 0.732– 0.901. Conclusion: Eye-tracking based measurements of gaze fixation and pupil reaction may be useful biomarkers of PD diagnosis. However, larger studies of eye-tracking parameters integrated into the screening of patients with suspected PD are necessary, to further investigate and confirm their diagnostic value.

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Do you see what I mean?: Using mobile eye tracking to capture parent–child dynamics in the context of anxiety risk

Development and Psychopathology ◽

10.1017/s0954579420001601 ◽

2021 ◽

pp. 1-16

Author(s):

Leigha A. MacNeill ◽

Xiaoxue Fu ◽

Kristin A. Buss ◽

Koraly Pérez-Edgar

Keyword(s):

Eye Tracking ◽

Positive Reinforcement ◽

Parental Behavior ◽

Anxiety Level ◽

Eye Tracker ◽

Fine Grained ◽

Controlling Parenting ◽

Attractor Strength ◽

Child Age ◽

Mobile Eye Tracking

Abstract Temperamental behavioral inhibition (BI) is a robust endophenotype for anxiety characterized by increased sensitivity to novelty. Controlling parenting can reinforce children's wariness by rewarding signs of distress. Fine-grained, dynamic measures are needed to better understand both how children perceive their parent's behaviors and the mechanisms supporting evident relations between parenting and socioemotional functioning. The current study examined dyadic attractor patterns (average mean durations) with state space grids, using children's attention patterns (captured via mobile eye tracking) and parental behavior (positive reinforcement, teaching, directives, intrusion), as functions of child BI and parent anxiety. Forty 5- to 7-year-old children and their primary caregivers completed a set of challenging puzzles, during which the child wore a head-mounted eye tracker. Child BI was positively correlated with proportion of parent's time spent teaching. Child age was negatively related, and parent anxiety level was positively related, to parent-focused/controlling parenting attractor strength. There was a significant interaction between parent anxiety level and child age predicting parent-focused/controlling parenting attractor strength. This study is a first step to examining the co-occurrence of parenting behavior and child attention in the context of child BI and parental anxiety levels.

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Eye Movements as a Means to Evaluate Operation Interface of Flat Knitting Machine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.607.664 ◽

2014 ◽

Vol 607 ◽

pp. 664-668

Author(s):

Zhi Hui Liu ◽

Sheng Ze Wang ◽

Qiong Shen ◽

Jia Jun Feng

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Objective Evaluation ◽

Layout Design ◽

Eye Tracker ◽

Heat Maps ◽

Machine Operation

This study investigates the characteristics of eye movements by operating flat knitting machine. For the objective evaluation purpose of the flat knitting machine operation interface, we arrange participants finish operation tasks on the interface, then use eye tracker to analyze and evaluate the layout design. Through testing of the different layout designs, we get fixation sequences, the count of fixation, heat maps, and fixation length. The results showed that the layout design could significantly affect the eye-movement, especially the fixation sequences and the heat maps, the count of fixation and fixation length are always impacted by operation tasks. Overall, data obtained from eye movements can not only be used to evaluate the operation interface, but also significantly enhance the layout design of the flat knitting machine.

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Why subtitle speed matters: Evidence from word skipping and rereading

Applied Psycholinguistics ◽

10.1017/s0142716421000503 ◽

2021 ◽

pp. 1-26

Author(s):

Jan-Louis Kruger ◽

Natalia Wisniewska ◽

Sixin Liao

Keyword(s):

Eye Movements ◽

Eye Tracking ◽

Eye Movement ◽

Lexical Processing ◽

Situation Model ◽

Linguistic Processing ◽

Reading Behavior ◽

New Findings ◽

Word Skipping

Abstract High subtitle speed undoubtedly impacts the viewer experience. However, little is known about how fast subtitles might impact the reading of individual words. This article presents new findings on the effect of subtitle speed on viewers’ reading behavior using word-based eye-tracking measures with specific attention to word skipping and rereading. In multimodal reading situations such as reading subtitles in video, rereading allows people to correct for oculomotor error or comprehension failure during linguistic processing or integrate words with elements of the image to build a situation model of the video. However, the opportunity to reread words, to read the majority of the words in the subtitle and to read subtitles to completion, is likely to be compromised when subtitles are too fast. Participants watched videos with subtitles at 12, 20, and 28 characters per second (cps) while their eye movements were recorded. It was found that comprehension declined as speed increased. Eye movement records also showed that faster subtitles resulted in more incomplete reading of subtitles. Furthermore, increased speed also caused fewer words to be reread following both horizontal eye movements (likely resulting in reduced lexical processing) and vertical eye movements (which would likely reduce higher-level comprehension and integration).

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Automated Filtering of Eye Movements Using Dynamic AOI in Multiple Granularity Levels

International Journal of Multimedia Data Engineering and Management ◽

10.4018/ijmdem.2021010104 ◽

2021 ◽

Vol 12 (1) ◽

pp. 49-64

Author(s):

Gavindya Jayawardena ◽

Sampath Jayarathna

Keyword(s):

Eye Movements ◽

Eye Tracking ◽

Eye Movement ◽

Eye Gaze ◽

Movement Analysis ◽

Movement Data ◽

Bounding Boxes ◽

Multiple Granularity ◽

Instance Segmentation ◽

Segmentation Models

Eye-tracking experiments involve areas of interest (AOIs) for the analysis of eye gaze data. While there are tools to delineate AOIs to extract eye movement data, they may require users to manually draw boundaries of AOIs on eye tracking stimuli or use markers to define AOIs. This paper introduces two novel techniques to dynamically filter eye movement data from AOIs for the analysis of eye metrics from multiple levels of granularity. The authors incorporate pre-trained object detectors and object instance segmentation models for offline detection of dynamic AOIs in video streams. This research presents the implementation and evaluation of object detectors and object instance segmentation models to find the best model to be integrated in a real-time eye movement analysis pipeline. The authors filter gaze data that falls within the polygonal boundaries of detected dynamic AOIs and apply object detector to find bounding-boxes in a public dataset. The results indicate that the dynamic AOIs generated by object detectors capture 60% of eye movements & object instance segmentation models capture 30% of eye movements.

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