-
Sensors (Basel, Switzerland) Jun 2022Electro-oculography (EOG)-based brain-computer interface (BCI) is a relevant technology influencing physical medicine, daily life, gaming and even the aeronautics field.... (Review)
Review
Electro-oculography (EOG)-based brain-computer interface (BCI) is a relevant technology influencing physical medicine, daily life, gaming and even the aeronautics field. EOG-based BCI systems record activity related to users' intention, perception and motor decisions. It converts the bio-physiological signals into commands for external hardware, and it executes the operation expected by the user through the output device. EOG signal is used for identifying and classifying eye movements through active or passive interaction. Both types of interaction have the potential for controlling the output device by performing the user's communication with the environment. In the aeronautical field, investigations of EOG-BCI systems are being explored as a relevant tool to replace the manual command and as a communicative tool dedicated to accelerating the user's intention. This paper reviews the last two decades of EOG-based BCI studies and provides a structured design space with a large set of representative papers. Our purpose is to introduce the existing BCI systems based on EOG signals and to inspire the design of new ones. First, we highlight the basic components of EOG-based BCI studies, including EOG signal acquisition, EOG device particularity, extracted features, translation algorithms, and interaction commands. Second, we provide an overview of EOG-based BCI applications in the real and virtual environment along with the aeronautical application. We conclude with a discussion of the actual limits of EOG devices regarding existing systems. Finally, we provide suggestions to gain insight for future design inquiries.
Topics: Algorithms; Brain-Computer Interfaces; Computers; Electroencephalography; Electrooculography; Eye Movements; Humans; User-Computer Interface
PubMed: 35808414
DOI: 10.3390/s22134914 -
Journal of Clinical Sleep Medicine :... Apr 2008Visual sleep scoring is the obligatory reference for sleep analysis. An essential step in sleep scoring is sleep staging. This technique was first described in 1937 and... (Review)
Review
Visual sleep scoring is the obligatory reference for sleep analysis. An essential step in sleep scoring is sleep staging. This technique was first described in 1937 and later adapted 3 times: first, in 1957, after the detection of rapid eye movement (REM) sleep, when electrooculography (EOG) was added; second, in 1968, when sleep staging was standardized and electromyography (EMG) was added; and third, in 2007, to integrate accumulated knowledge from sleep science, adding arousals and respiratory, cardiac, and movement events. In spite of the dramatic changes that have taken place in recording and storing techniques, sleep staging has undergone surprisingly few changes. The argument of the present comment is that sleep staging was appropriate as long as sleep biosignals were recorded in the analog mode as curves on paper, whereas this staging may be insufficient for digitally recorded and stored sleep data. Limitations of sleep staging are critically discussed and alternative strategies of sleep analysis are emphasized.
Topics: Electroencephalography; Electromyography; Electrooculography; Humans; Sleep Stages; Sleep Wake Disorders
PubMed: 18468306
DOI: No ID Found -
Sensors (Basel, Switzerland) Jun 2019Eye movements generate electric signals, which a user can employ to control his/her environment and communicate with others. This paper presents a review of previous... (Review)
Review
Eye movements generate electric signals, which a user can employ to control his/her environment and communicate with others. This paper presents a review of previous studies on such electric signals, that is, electrooculograms (EOGs), from the perspective of human-computer interaction (HCI). EOGs represent one of the easiest means to estimate eye movements by using a low-cost device, and have been often considered and utilized for HCI applications, such as to facilitate typing on a virtual keyboard, moving a mouse, or controlling a wheelchair. The objective of this study is to summarize the experimental procedures of previous studies and provide a guide for researchers interested in this field. In this work the basic characteristics of EOGs, associated measurements, and signal processing and pattern recognition algorithms are briefly reviewed, and various applications reported in the existing literature are listed. It is expected that EOGs will be a useful source of communication in virtual reality environments, and can act as a valuable communication tools for people with amyotrophic lateral sclerosis.
Topics: Algorithms; Amyotrophic Lateral Sclerosis; Communication Aids for Disabled; Electrooculography; Eye Movements; Humans; Pattern Recognition, Automated; Signal Processing, Computer-Assisted; User-Computer Interface
PubMed: 31207949
DOI: 10.3390/s19122690 -
Brazilian Journal of Otorhinolaryngology 2010Electronystagmography (ENG) and videonystagmography (VNG) are eye movement recording methods used for the evaluation of balance disorders. (Comparative Study)
Comparative Study Review
UNLABELLED
Electronystagmography (ENG) and videonystagmography (VNG) are eye movement recording methods used for the evaluation of balance disorders.
AIM
To compare literature information on the similarities, differences, advantages e disadvantages between ENG and VNG.
MATERIALS AND METHODS
review of the scientific literature.
RESULTS
ENG and VNG are very helpful methods for evaluating balance disorders, due to their capacity to recognize signs of peripheral or central vestibular dysfunction and to pinpoint the side of the lesion. Major advantages of VNG are related to calibration, temporospatial resolution, and recording of horizontal, vertical and torsional eye movements.
CONCLUSION
VNG is a new technology that presents advantages in the evaluation of eye movements; however, despite its disadvantages, ENG is still considered a valuable test in the clinical setting.
Topics: Electronystagmography; Electrooculography; Humans; Sensitivity and Specificity; Vestibular Diseases; Video Recording
PubMed: 20658023
DOI: 10.1590/S1808-86942010000300021 -
Sensors (Basel, Switzerland) Jun 2020Bioelectrical or electrophysiological signals generated by living cells or tissues during daily physiological activities are closely related to the state of the body and... (Review)
Review
Bioelectrical or electrophysiological signals generated by living cells or tissues during daily physiological activities are closely related to the state of the body and organ functions, and therefore are widely used in clinical diagnosis, health monitoring, intelligent control and human-computer interaction. Ag/AgCl electrodes with wet conductive gels are widely used to pick up these bioelectrical signals using electrodes and record them in the form of electroencephalograms, electrocardiograms, electromyography, electrooculograms, etc. However, the inconvenience, instability and infection problems resulting from the use of gel with Ag/AgCl wet electrodes can't meet the needs of long-term signal acquisition, especially in wearable applications. Hence, focus has shifted toward the study of dry electrodes that can work without gels or adhesives. In this paper, a retrospective overview of the development of dry electrodes used for monitoring bioelectrical signals is provided, including the sensing principles, material selection, device preparation, and measurement performance. In addition, the challenges regarding the limitations of materials, fabrication technologies and wearable performance of dry electrodes are discussed. Finally, the development obstacles and application advantages of different dry electrodes are analyzed to make a comparison and reveal research directions for future studies.
Topics: Electric Conductivity; Electrocardiography; Electrodes; Electroencephalography; Electromyography; Electrooculography; Humans
PubMed: 32610658
DOI: 10.3390/s20133651 -
Journal of Neurology, Neurosurgery, and... Aug 1995
Review
Topics: Electronystagmography; Electrooculography; Eye Movements; Humans; Ocular Motility Disorders
PubMed: 7629523
DOI: 10.1136/jnnp.59.2.115 -
Acta Ophthalmologica Scandinavica Aug 2001To report a unique case of a woman who developed simultaneous bilateral maculopathy presumed to result from intake of sertraline hydrochloride, a serotonin reuptake...
PURPOSE
To report a unique case of a woman who developed simultaneous bilateral maculopathy presumed to result from intake of sertraline hydrochloride, a serotonin reuptake inhibitor.
METHODS
Full clinical ocular examination, color vision testing, automated static perimetry, electroretinography, electrooculography and fundus fluorescein angiography were performed. Living members of her family were also examined.
RESULTS
The patient had normal electroretinography and electrooculography results. Automated static perimetry showed generalized reduction of sensitivity and central scotomas. Macular lesions resolved 6 months after discontinuation of sertraline, however, during twenty months of follow-up her visual acuity and abnormalities in other psychophysical tests did not improve.
CONCLUSION
Patients started on sertraline should be informed of the potential risk of developing maculopathy, and they should be examined regularly to detect possible early alterations.
Topics: Electrooculography; Electroretinography; Female; Fluorescein Angiography; Humans; Macula Lutea; Middle Aged; Retinal Diseases; Selective Serotonin Reuptake Inhibitors; Sertraline; Visual Acuity
PubMed: 11453869
DOI: 10.1034/j.1600-0420.2001.079004428.x -
Military Medicine Oct 2022Objectively determining soldiers' fatigue levels could help prevent injuries or accidents resulting from inattention or decreased alertness. Eye-tracking technologies,... (Review)
Review
INTRODUCTION
Objectively determining soldiers' fatigue levels could help prevent injuries or accidents resulting from inattention or decreased alertness. Eye-tracking technologies, such as optical eye tracking (OET) and electrooculography (EOG), are often used to monitor fatigue. Eyeblinks-especially blink frequency and blink duration-are known as easily observable and valid biomarkers of fatigue. Currently, various eye trackers (i.e., eye-tracking glasses) are available on the market using either OET or EOG technologies. These wearable eye trackers offer several advantages, including unobtrusive functionality, practicality, and low costs. However, several challenges and limitations must be considered when implementing these technologies in the field to monitor fatigue levels. This review investigates the feasibility of eye tracking in the field focusing on the practical applications in military operational environments.
MATERIALS AND METHOD
This paper summarizes the existing literature about eyeblink dynamics and available wearable eye-tracking technologies, exposing challenges and limitations, as well as discussing practical recommendations on how to improve the feasibility of eye tracking in the field.
RESULTS
So far, no eye-tracking glasses can be recommended for use in a demanding work environment. First, eyeblink dynamics are influenced by multiple factors; therefore, environments, situations, and individual behavior must be taken into account. Second, the glasses' placement, sunlight, facial or body movements, vibrations, and sweat can drastically decrease measurement accuracy. The placement of the eye cameras for the OET and the placement of the electrodes for the EOG must be chosen consciously, the sampling rate must be minimal 200 Hz, and software and hardware must be robust to resist any factors influencing eye tracking.
CONCLUSION
Monitoring physiological and psychological readiness of soldiers, as well as other civil professionals that face higher risks when their attention is impaired or reduced, is necessary. However, improvements to eye-tracking devices' hardware, calibration method, sampling rate, and algorithm are needed in order to accurately monitor fatigue levels in the field.
Topics: Humans; Military Personnel; Electrooculography; Fatigue; Wearable Electronic Devices; Attention
PubMed: 34915554
DOI: 10.1093/milmed/usab509 -
Sensors (Basel, Switzerland) Jul 2021Saccadic electrooculograms are discrete biosignals that contain the instantaneous angular position of the human eyes as a response to saccadic visual stimuli. These...
Saccadic electrooculograms are discrete biosignals that contain the instantaneous angular position of the human eyes as a response to saccadic visual stimuli. These signals are essential to monitor and evaluate several neurological diseases, such as Spinocerebellar Ataxia type 2 (SCA2). For this, biomarkers such as peak velocity, latency and duration are computed. To compute these biomarkers, we need to obtain the velocity profile of the signals using numerical differentiation methods. These methods are affected by the noise present in the electrooculograms, specially in subjects that suffer neurological diseases. This noise complicates the comparison of the differentiation methods using real saccadic signals because of the impossibility of establishing exact saccadic onset and offset points. In this work, we evaluate 16 differentiation methods by the design of an experiment that uses synthetic saccadic electrooculograms generated from parametric models of both healthy subjects and subjects suffering from Spinocerebellar Ataxia type 2 (SCA2). For these synthetic electrooculograms the exact velocity profile is known, hence we can use them as a reference for comparison and error computing for the tasks of saccade identification and saccade biomarker computing. Finally, we identify the best fitting method or methods for each evaluated task.
Topics: Electrooculography; Humans; Saccades
PubMed: 34372261
DOI: 10.3390/s21155021 -
Scientific Reports Aug 2021Veterinary and human medicine are still seeking a conclusive explanation of the function of sleep, including the change in sleep behaviour over the course of an...
Veterinary and human medicine are still seeking a conclusive explanation of the function of sleep, including the change in sleep behaviour over the course of an individual's lifetime. In human medicine, sleep disorders and abnormalities in the electroencephalogram are used for prognostic statements, therapeutic means and diagnoses. To facilitate such use in foal medicine, we monitored 10 foals polysomnographically for 48 h. Via 10 attached cup electrodes, brain waves were recorded by electroencephalography, eye movements by electrooculography and muscle activity by electromyography. Wireless polysomnographs allowed us to measure the foals in their home stables. In addition, each foal was simultaneously monitored with infrared video cameras. By combining the recorded data, we determined the time budgeting of the foals over 48 h, whereby the states of vigilance were divided into wakefulness, light sleep, slow-wave sleep and rapid-eye-movement sleep, and the body positions into standing, suckling, sternal recumbency and lateral recumbency. The results of the qualitative analyses showed that the brain waves of the foals differ in their morphology from those previously reported for adult horses. The quantitative data analyses revealed that foals suckle throughout all periods of the day, including night-time. The results of our combined measurements allow optimizing the daily schedule of the foals according to their sleep and activity times. We recommend that stall rest should begin no later than 9.00 p.m. and daily stable work should be done in the late afternoon.
Topics: Animals; Brain; Electroencephalography; Electromyography; Electrooculography; Evaluation Studies as Topic; Eye Movements; Horses; Polysomnography; Rest; Sleep, REM; Wakefulness
PubMed: 34381127
DOI: 10.1038/s41598-021-95770-5