Journal articles on the topic 'Eye Movement Measurements'
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KONOSU, Tsutomu, and Tadahiko FUKUDA. "Eye movement measurements SFC symposium." Japanese journal of ergonomics 30, no. 1 (1994): 57–58. http://dx.doi.org/10.5100/jje.30.57.
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Lee, Youngkeun, Yadav Sunil Kumar, Daehyeon Lee, Jihee Kim, Junggwon Kim, Jisang Yoo, and Soonchul Kwon. "An Extended Method for Saccadic Eye Movement Measurements Using a Head-Mounted Display." Healthcare 8, no. 2 (April 21, 2020): 104. http://dx.doi.org/10.3390/healthcare8020104.
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Saccadic eye movement is an important ability in our daily life and is especially important in driving and sports. Traditionally, the Developmental Eye Movement (DEM) test and the King–Devick (K-D) test have been used to measure saccadic eye movement, but these only involve measurements with “adjusted time”. Therefore, a different approach is required to obtain the eye movement speed and reaction rate in detail, as some are rapid eye movements, while others are slow actions, and vice versa. This study proposed an extended method that can acquire the “rest time” and “transfer time”, as well as the “adjusted time”, by implementing a virtual reality-based DEM test, using a FOVE virtual reality (VR) head-mounted display (HMD), equipped with an eye-tracking module. This approach was tested in 30 subjects with normal vision and no ophthalmologic disease by using a 2-diopter (50-cm) distance. This allowed for measurements of the “adjusted time” and the “rest time” for focusing on each target number character, the “transfer time” for moving to the next target number character, and recording of the gaze-tracking log. The results of this experiment showed that it was possible to analyze more parameters of the saccadic eye movement with the proposed method than with the traditional methods.
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Souto, David, Jayesha Chudasama, Dirk Kerzel, and Alan Johnston. "Motion integration is anisotropic during smooth pursuit eye movements." Journal of Neurophysiology 121, no. 5 (May 1, 2019): 1787–97. http://dx.doi.org/10.1152/jn.00591.2018.
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Smooth pursuit eye movements (pursuit) are used to minimize the retinal motion of moving objects. During pursuit, the pattern of motion on the retina carries not only information about the object movement but also reafferent information about the eye movement itself. The latter arises from the retinal flow of the stationary world in the direction opposite to the eye movement. To extract the global direction of motion of the tracked object and stationary world, the visual system needs to integrate ambiguous local motion measurements (i.e., the aperture problem). Unlike the tracked object, the stationary world’s global motion is entirely determined by the eye movement and thus can be approximately derived from motor commands sent to the eye (i.e., from an efference copy). Because retinal motion opposite to the eye movement is dominant during pursuit, different motion integration mechanisms might be used for retinal motion in the same direction and opposite to pursuit. To investigate motion integration during pursuit, we tested direction discrimination of a brief change in global object motion. The global motion stimulus was a circular array of small static apertures within which one-dimensional gratings moved. We found increased coherence thresholds and a qualitatively different reflexive ocular tracking for global motion opposite to pursuit. Both effects suggest reduced sampling of motion opposite to pursuit, which results in an impaired ability to extract coherence in motion signals in the reafferent direction. We suggest that anisotropic motion integration is an adaptation to asymmetric retinal motion patterns experienced during pursuit eye movements. NEW & NOTEWORTHY This study provides a new understanding of how the visual system achieves coherent perception of an object’s motion while the eyes themselves are moving. The visual system integrates local motion measurements to create a coherent percept of object motion. An analysis of perceptual judgments and reflexive eye movements to a brief change in an object’s global motion confirms that the visual and oculomotor systems pick fewer samples to extract global motion opposite to the eye movement.
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Destyanto, Twin Yoshua R., and Ray F. Lin. "Evaluating the Effectiveness of Complexity Features of Eye Movement on Computer Activities Detection." Healthcare 10, no. 6 (May 31, 2022): 1016. http://dx.doi.org/10.3390/healthcare10061016.
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Recently, tools developed for detecting human activities have been quite prominent in contributing to health issue prevention and long-term healthcare. For this occasion, the current study aimed to evaluate the performance of eye-movement complexity features (from multi-scale entropy analysis) compared to eye-movement conventional features (from basic statistical measurements) on detecting daily computer activities, comprising reading an English scientific paper, watching an English movie-trailer video, and typing English sentences. A total of 150 students participated in these computer activities. The participants’ eye movements were captured using a desktop eye-tracker (GP3 HD Gazepoint™ Canada) while performing the experimental tasks. The collected eye-movement data were then processed to obtain 56 conventional and 550 complexity features of eye movement. A statistic test, analysis of variance (ANOVA), was performed to screen these features, which resulted in 45 conventional and 379 complexity features. These eye-movement features with four combinations were used to build 12 AI models using Support Vector Machine, Decision Tree, and Random Forest (RF). The comparisons of the models showed the superiority of complexity features (85.34% of accuracy) compared to conventional features (66.98% of accuracy). Furthermore, screening eye-movement features using ANOVA enhances 2.29% of recognition accuracy. This study proves the superiority of eye-movement complexity features.
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Gruters, Kurtis G., David L. K. Murphy, Cole D. Jenson, David W. Smith, Christopher A. Shera, and Jennifer M. Groh. "The eardrums move when the eyes move: A multisensory effect on the mechanics of hearing." Proceedings of the National Academy of Sciences 115, no. 6 (January 23, 2018): E1309—E1318. http://dx.doi.org/10.1073/pnas.1717948115.
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Interactions between sensory pathways such as the visual and auditory systems are known to occur in the brain, but where they first occur is uncertain. Here, we show a multimodal interaction evident at the eardrum. Ear canal microphone measurements in humans (n = 19 ears in 16 subjects) and monkeys (n = 5 ears in three subjects) performing a saccadic eye movement task to visual targets indicated that the eardrum moves in conjunction with the eye movement. The eardrum motion was oscillatory and began as early as 10 ms before saccade onset in humans or with saccade onset in monkeys. These eardrum movements, which we dub eye movement-related eardrum oscillations (EMREOs), occurred in the absence of a sound stimulus. The amplitude and phase of the EMREOs depended on the direction and horizontal amplitude of the saccade. They lasted throughout the saccade and well into subsequent periods of steady fixation. We discuss the possibility that the mechanisms underlying EMREOs create eye movement-related binaural cues that may aid the brain in evaluating the relationship between visual and auditory stimulus locations as the eyes move.
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Goffart, Laurent, Clara Bourrelly, and Jean-Charles Quinton. "Neurophysiology of visually guided eye movements: critical review and alternative viewpoint." Journal of Neurophysiology 120, no. 6 (December 1, 2018): 3234–45. http://dx.doi.org/10.1152/jn.00402.2018.
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In this article, we perform a critical examination of assumptions that led to the assimilation of measurements of the movement of a rigid body in the physical world to parameters encoded within brain activity. In many neurophysiological studies of goal-directed eye movements, equivalence has indeed been made between the kinematics of the eyes or of a targeted object and the associated neuronal processes. Such a way of proceeding brings up the reduction encountered in projective geometry when a multidimensional object is being projected onto a one-dimensional segment. The measurement of a movement indeed consists of generation of a series of numerical values from which magnitudes such as amplitude, duration, and their ratio (speed) are calculated. By contrast, movement generation consists of activation of multiple parallel channels in the brain. Yet, for many years, kinematic parameters were supposed to be encoded in brain activity, even though the neuronal image of most physical events is distributed both spatially and temporally. After explaining why the “neuronalization” of such parameters is questionable for elucidating the neural processes underlying the execution of saccadic and pursuit eye movements, we propose an alternative to the framework that has dominated the last five decades. A viewpoint is presented in which these processes follow principles that are defined by intrinsic properties of the brain (population coding, multiplicity of transmission delays, synchrony of firing, connectivity). We propose reconsideration of the time course of saccadic and pursuit eye movements as the restoration of equilibria between neural populations that exert opposing motor tendencies.
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Wilkinson, F., O. Karanovic, EC Ross, L. Lillakas, and MJ Steinbach. "Ocular Motor Measures in Migraine with and Without Aura." Cephalalgia 26, no. 6 (June 2006): 660–71. http://dx.doi.org/10.1111/j.1468-2982.2006.01091.x.
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The purpose of this study was to examine basic ocular motor function in individuals with migraine. We used an infrared eye-tracking system to measure horizontal smooth pursuit to a sinusoidal target, saccades to horizontal target displacements of 5–20°, and the stability of fixation in 19 migraine without aura (MoA), 19 migraine with aura (MA) and 19 headache-free control (C) subjects. Eye movement measurements were made at two target displacement rates and against both homogeneous grey and patterned backgrounds. We found no statistically significant differences between migraine and control subjects in any of the eye movement parameters measured, but did find highly significant effects of both target speed and background pattern in all groups. Our results do not provide support for subclinical cerebellar impairment in migraineurs, and do provide evidence that previously described visual abnormalities in migraine are not artefacts of abnormal fixation or eye movements.
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Henn, Volker, and Dominik Straumann. "Three-dimensional eye movement recording for clinical application*." Journal of Vestibular Research 9, no. 3 (June 1, 1999): 157–62. http://dx.doi.org/10.3233/ves-1999-9302.
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Methods to measure eye rotations in 3D have developed to a stage where routine clinical application is realistic. Besides the equipment, it requires a basic understanding of 3-dimensional geometry for calibration and interpretation. Relevant parameters are orientation, displacement and thickness of Listing's plane for spontaneous or goal-directed eye movements, and counterrolling or nystagmus with a roll component for vestibular function. The method with the highest temporal and spatial resolution is the magnetic search coil technique. Video-based systems are still slow and cannot be used to characterize saccades. Often, the task of reconstructing the 3-dimensional eye position from a 2-dimensional image of the eye is underestimated. Search coil measurements have shown no firm correlation between the orientation of Listing's plane and “classical” landmarks like stereotaxic head position, emphasizing that Listing's plane is functionally, and not anatomically, determined.
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Rigatto, H., M. Moore, and D. Cates. "Fetal breathing and behavior measured through a double-wall Plexiglas window in sheep." Journal of Applied Physiology 61, no. 1 (July 1, 1986): 160–64. http://dx.doi.org/10.1152/jappl.1986.61.1.160.
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The inability to see the fetus makes the assessment of fetal behavior difficult. To circumvent this problem we implanted a Plexiglas window in the left flank of the ewe. Fetuses were instrumented for measurements of sleep, breathing, and swallowing. Ten fetal sheep were studied on 32 occasions. Six fetuses were delivered through the window at term, and postnatal behavior was compared with intrauterine behavior. Fetuses observed during resting conditions alternated between periods of quiet sleep [high-voltage electrocortical activity (ECoG)] and active or rapid-eye-movement sleep (low-voltage ECoG). In quiet sleep, movements were absent except for periodic generalized electromyographic discharges. Eye and breathing movements were rare or absent. Swallowing was also absent. In active sleep, movements were increased with powerful breathing and swallowing activity. Fetal wakefulness defined by open eyes and purposeful movements of the head was never seen in utero but was clearly observed after delivery. We conclude that fetal wakefulness as defined postnatally was not able to be demonstrated in utero.
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Fox, P. T., J. M. Fox, M. E. Raichle, and R. M. Burde. "The role of cerebral cortex in the generation of voluntary saccades: a positron emission tomographic study." Journal of Neurophysiology 54, no. 2 (August 1, 1985): 348–69. http://dx.doi.org/10.1152/jn.1985.54.2.348.
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The purpose of this study was to define the location and behavior of cerebral structures within the normal human brain that participate in the generation of voluntary saccadic eye movements. Changes in regional cerebral blood flow (rCBF) during task performance were assumed to reflect like changes in regional neuronal activity induced by the task. The locations of all rCBF changes were described in stereotaxic coordinates. Cerebral blood flow (CBF) was measured with positron emission tomography (PET) and bolus intravenous injection of H2(15)O. The use of H2(15)O with PET allowed six, seven-slice measurements of brain blood flow to be made in rapid sequence for each subject, without removing the subject from the tomograph between scans. Nine paid normal volunteers were studied. The paradigm included three saccadic eye-movement (SEM) conditions, one finger-movement condition and two control conditions (initial and final). The three SEM conditions allowed comparisons to be drawn between targeted versus untargeted SEMs, auditorily cued versus visually cued SEMs, and stochastic versus rhythmic SEMs. All tasks were simple and deterministic in that each movement exactly mirrored the preceding movement: finger flexion then extension, saccade-left then saccade-right. Saccadic eye movements were associated with rCBF increases within the frontal eye fields, the supplementary motor area, and the cerebellum. Finger movements were associated with rCBF changes within the sensorimotor hand areas, the supplementary motor area, and the cerebellum. The frontal eye fields were discrete cortical regions consistently active during the generation of voluntary SEMs and uninfluenced by target presence, type of cue, or task complexity, indicating a predominantly motor function. The supplementary motor area (SMA) was consistently active during all motor tasks and was uninfluenced by the degree of task complexity or stochasticity. A role for SMA in establishing "motor set" during both simple and complex motor tasks is suggested. An anterior-posterior somatotopy was found for SMA-eye (anterior) versus SMA-hand (posterior). Lateral occipital visual association cortex activation was present only during targeted saccadic conditions.(ABSTRACT TRUNCATED AT 400 WORDS)
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Tsitsi, Panagiota, Mattias Nilsson Benfatto, Gustaf Öqvist Seimyr, Olof Larsson, Per Svenningsson, and Ioanna Markaki. "Fixation Duration and Pupil Size as Diagnostic Tools in Parkinson’s Disease." Journal of Parkinson's Disease 11, no. 2 (April 13, 2021): 865–75. http://dx.doi.org/10.3233/jpd-202427.
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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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CRONIN, THOMAS W., JAYGOPAL N. NAIR, ROBERT D. DOYLE, and ROY L. CALDWELL. "Ocular Tracking of Rapidly Moving Visual Targets by Stomatopod Crustaceans." Journal of Experimental Biology 138, no. 1 (September 1, 1988): 155–79. http://dx.doi.org/10.1242/jeb.138.1.155.
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1. Ocular tracking in two species of stomatopod crustaceans, Squilla empusa (Say) and Gonodactylus oerstedii (Hansen), was studied by presenting animals with small targets moving to their right and left. 2. Squilla empusa showed no indication of ocular movement responses synchronized with the target's motion, whereas Gonodactylus oerstedii often tracked the target through large angular amplitudes. 3. The region of visual fixation in G. oerstedii is probably the ommatidial patches in line with the eyecup axis. This is suggested by the arrangement of ommatidial axes on the eye's circumference, and by the alignment of the eyes and the rotational motions they make as they observe an approaching target. 4. Tracking is irregular, probably because the animal pays attention to the target only intermittently. Targets are most stimulatory as they move nearly in front of an animal. Eye tracking responses become larger, more frequent and more accurate with increasingly anterior target positions. 5. During visual tracking, the eyes perform both smooth and saccadic tracking movements. Eye movements in the size range 7.5°–15° are made to near the position of the target at movement onset, but are less accurate relative to the target's position at the end of the movement. 6. During visual tracking, the two eyes apparently act with complete independence. Movements of one eye are uncorrelated with movements of the other, both for extreme and central locations of the moving target. 7. The existence of ocular independence during smooth pursuit and saccadic tracking in G. oerstedii may be possible because of the redundancy of visual fields existing in each eye, which could permit monocular measurements of distance to a viewed object. If so, each eye is capable of providing a complete description of the location of a target in space.
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Otero-Millan, Jorge, T. Maxwell Parker, Shervin Badihian, Ahmed Hassoon, Ali S. Saber Tehrani, Nathan Farrell, and David E. Newman-Toker. "Eye and head movement recordings using smartphone: measurements of accuracy and precision." Journal of Vision 22, no. 14 (December 5, 2022): 3239. http://dx.doi.org/10.1167/jov.22.14.3239.
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Maka, Erika, Olga Lukats, Tamas Vizkelety, Zsolt Markella, Maria Kis, Janos Nemeth, and Jozsef Barabas. "Measurements of Orbital Volume using Cone-Beam Computed Tomography in Eye Movement Abnormalities." European Journal of Ophthalmology 24, no. 1 (January 2014): 101–6. http://dx.doi.org/10.5301/ejo.5000303.
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Kanematsu, Hideyuki, Dana M. Barry, Tasuya Shirai, Masashi Kawaguchi, Nobuyuki Ogawa, Kuniaki Yajima, Katsuko T. Nakahira, Toshiro Kobayashi, and Michiko Yoshitake. "Measurements of Eye Movement and Teachers’ Concentration during the Preparation of Teaching Materials." Procedia Computer Science 159 (2019): 1499–506. http://dx.doi.org/10.1016/j.procs.2019.09.320.
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Ward, Lindsey M., and Zoi Kapoula. "Disconjugate Eye Movements in Dyslexic Adolescents While Viewing Op Art: A Creative Handicap?" Brain Sciences 12, no. 7 (June 26, 2022): 835. http://dx.doi.org/10.3390/brainsci12070835.
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Op art was created, in part, to produce illusions of movement. Given that dyslexics have been shown to have impaired visuo-postural axis deficits, it may be possible that dyslexics see illusions different than their non-dyslexic peers. To test this theory, we measured eye movement and posture in 47 dyslexic (18 female, 29 male; mean age 15.4) and 44 non dyslexic (22 female, 22 male; mean age 14.8) adolescents while they viewed three works of art by Op artist Bridget Riley. They then responded to a questionnaire about how they felt while viewing the artworks. Dyslexics demonstrated significantly slower saccades in terms of average velocity that was particularly disturbed in paintings that manipulated depth. Subjectively, dyslexics felt much more destabilized compared to their peers; however, there was not a significant difference in objective postural measurements between the two groups. The sensation of destabilization was positively correlated with appreciation in non-dyslexic adolescents. These subjective results suggest that dyslexics may be more sensitive to movement in depth, which could be related to the instability in vergence movements. Whereas this instability represents a hinderance in relation to reading, it could be an advantage while viewing paintings such as these.
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Krasnova, M. V., and K. A. Nefedova. "FORMATION OF CONSUMER PREFERENCES USING NEUROMARKETING TOOLS." Scientific Review: Theory and Practice 10, no. 9 (September 30, 2020): 2062–73. http://dx.doi.org/10.35679/2226-0226-2020-10-9-2062-2073.
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In this article, we say that marketing and advertising professionals have been aware of the limitations in traditional market research methods for decades, but only in recent years has science allowed the development of a more effective mechanism by which consumers’ thoughts can be deciphered and this is neuromarketing. Building an effective and successful communication policy through the use of a variety of technologies and promotion methods is one of the primary tasks of the effective functioning and development of the company in the market, as well as increasing its competitiveness. For this, in parallel with measurements of electroencephalography, magnetic resonance imaging, brain scanners, galvanic skin response, an eye-tracking device is used, which allows one to accurately identify a stimulus that provides information about the consumer’s response to various commercial messages. Eye-tracking technology is that the respondent is shown a visual stimulus (static or dynamic), while a special device records the trajectory and metrics of the pupil movement. The respondent’s pupil is illuminated with infrared rays, while the trajectory of its movement is continuously recorded by several high-precision infrared cameras. The coordinates of the movement of the pupil are recorded in the database, subsequently the data is analyzed and qualitative and quantitative reports are drawn up. This tool is used to analyze and understand the reaction of people to products and promotions, which allows you to increase the effectiveness of product promotion to make them more effective. The purpose of this article is to show the role that eye-tracking plays in the correct understanding of consumer needs, words and emotions. The main advantage of eye-tracking is the impartiality of the tested respondents, since the equipment used in this technology records the natural reactions of a person (by studying the movement and reaction of the pupil), which cannot be imitated. The main tool for applying the technology is the eye-tracker device, which recognizes and records pupil positions and eye movements.
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Yoshida, Masako, and Akitoshi Seiyama. "Importance of two-dimensional gaze analyses in the assessment of reading performance in patients with retinitis pigmentosa." PLOS ONE 17, no. 12 (December 14, 2022): e0278682. http://dx.doi.org/10.1371/journal.pone.0278682.
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The causes of reading difficulties in people with peripheral visual field loss are not fully understood. We conducted a two-dimensional gaze analysis on eye movements during reading in patients with retinitis pigmentosa to investigate the causes of reading difficulties in relation to the central visual field using a binocular eye mark recorder (EMR-9). Twenty-seven patients with retinitis pigmentosa whose central visual field narrowed to ≤ 20° using Goldmann kinetic perimetry (I/4 target) and this present study included eight healthy participants. The participants’ visual acuities were corrected to better than +0.4 logMAR. Correlations and multivariate regression analyses were investigated between the number of letters read correctly, the I/4 central visual field, V/4 perifoveal and peripheral visual field, and visual acuity. Multivariate regression analysis revealed that all these parameters played almost equal roles in the number of letters read correctly. In the two-dimensional gaze analysis, the task performance time of patients during reading increased as the I/4 central visual field narrowed. The task performance time was more clearly correlated with the rotation saccade (r = 0.428, p <0.05) and the distance of the vertical direction (ΣY) of eye movements (r = 0.624, p < 0.01), but not with regressive saccade and the distance of the horizontal direction (ΣX). Visual acuity was correlated with the task performance time (-0.436, <0.05) but not with eye movement directionality. Reading difficulties in patients with retinitis pigmentosa result from impaired eye movement directionality. Understanding eye measurements for people with tunnel vision required a two-dimensional gaze analysis. The two-dimensional gaze analysis also showed that the involvement of the perifoveal and peripheral visual fields, visual acuity, and I/4 central visual field was important for reading in people with tunnel vision.
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Chavant, Martin, and Zoï Kapoula. "Eye-Movement Deficits in Seniors with Hearing Aids: Cognitive and Multisensory Implications." Brain Sciences 12, no. 11 (October 24, 2022): 1425. http://dx.doi.org/10.3390/brainsci12111425.
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In recent years, there has been a growing body of literature highlighting the relationship between presbycusis and consequences in areas other than hearing. In particular, presbycusis is linked to depression, dementia, and cognitive decline. Among this literature, the effect of hearing aids, currently the most common method of treating presbycusis, is also a growing research topic. This pilot study aims to explore the effects of hearing aids on the cognitive and multisensory consequences of presbycusis. To that purpose, saccades and vergences eye movements were studied, towards visual and audiovisual targets, of a presbycusis population wearing hearing aids for an average of two years. These measurements were done whether or not participants were wearing their hearing aids. Eye-movement characteristics, particularly latencies (the reaction time taken to initiate an eye movement), allows one to measure attentional and multisensory characteristics. Previous studies showed that presbycusis was linked with an increase of saccade latencies and an improvement in audiovisual interaction capacities, i.e., latencies for audiovisual targets are shorter than those for visual targets. Eye movements are measured and analyzed with REMOBI and AIDEAL technologies. Results show a shortening, with hearing aids, of right saccade latencies to visual targets, suggesting an increase in attention and/or engagement. Yet, saccade latencies are not shorter for audiovisual vs. visual targets alone, neither when wearing hearing aids, nor without. Moreover, convergence latencies are particularly slow for any type of target and with or without hearing aids. The results suggest deficits for audiovisual interactions and the initiation of convergences in that population. These deficits could be part of the factors triggering the need to wear hearing aids. These results therefore show interesting relationships between hearing-aid wearing in a presbycusis population and oculomotricity and invite further research in this area.
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Lu, Yidu, and Nadine Sarter. "Modeling and inferring human trust in automation based on real- time eye tracking data." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 64, no. 1 (December 2020): 344–48. http://dx.doi.org/10.1177/1071181320641078.
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Trust miscalibration remains a major challenge for human-machine interaction. It can lead to misuse or disuse of automated systems. To date, most trust research has relied on subjective ratings and behavioral or physiological data to assess trust. Those trust measurements are discrete, disruptive and quite difficult to implement. To better understand the process of trust calibration, we propose eye tracking as an unobtrusive method for inferring trust levels in real time. Using an Unmanned Aerial Vehicle simulation, participants were exposed to varying levels of reliability of an automated target detection system. Eye movement data were captured and labeled as high or low trust based on subjective trust ratings. Feature extraction and raw eye movement data were compared as input for multiple classification modeling methods. Accuracy rates of 92% and 80%, respectively, were achieved with individual-level and group-level modeling, suggesting that eye tracking is a promising technique for tracing trust levels.
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Khoo, M. C., F. Yang, J. J. Shin, and P. R. Westbrook. "Estimation of dynamic chemoresponsiveness in wakefulness and non-rapid-eye-movement sleep." Journal of Applied Physiology 78, no. 3 (March 1, 1995): 1052–64. http://dx.doi.org/10.1152/jappl.1995.78.3.1052.
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We developed a method for quantifying dynamic chemoresponsiveness on the basis of the ventilatory response to pseudorandom binary CO2 stimulation. The dynamic chemoreflex gain (GD) and effective time delay (TDeff) relating breath-to-breath fluctuations in alveolar PCO2 to ventilation were evaluated at frequencies between 0 and 0.05 Hz. Application of the method to simulated “data” showed that estimation errors in GD and TDeff were most likely to be minimized in the range of 0.01–0.03 Hz, corresponding to periodicities of 30–100 s. Estimation of TDeff was generally more susceptible to error than that of GD because of the limited time resolution of the breath-by-breath measurements. In eight awake normal adults, we compared estimates of GD derived from the pseudorandom binary CO2 stimulation test with peripheral and central hypercapnic sensitivities deduced from single-breath and Read rebreathing measurements in the same subject. GD at 0.02 Hz was highly correlated with peripheral hypercapnic sensitivity but poorly correlated with central hypercapnic sensitivity, underscoring the importance of the peripheral chemoreflexes in mediating ventilatory responses to phasic stimuli. Application of the procedure to a different group of 10 healthy volunteers during wakefulness and stage 2 sleep showed decreases in GD in 8 subjects but increases in 2 subjects. However, for the group as a whole, GD and TDeff did not change significantly between wakefulness and sleep. The proposed method may provide information more pertinent to periodic breathing than traditional CO2 response tests do, since the chemoreflex responses to phasic variations in blood gases are likely to be important in determining ventilatory control during sleep.
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Zivotofsky, A. Z., K. G. Rottach, L. Averbuch-Heller, A. A. Kori, C. W. Thomas, L. F. Dell'Osso, and R. J. Leigh. "Saccades to remembered targets: the effects of smooth pursuit and illusory stimulus motion." Journal of Neurophysiology 76, no. 6 (December 1, 1996): 3617–32. http://dx.doi.org/10.1152/jn.1996.76.6.3617.
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1. Measurements were made in four normal human subjects of the accuracy of saccades to remembered locations of targets that were flashed on a 20 x 30 deg random dot display that was either stationary or moving horizontally and sinusoidally at +/-9 deg at 0.3 Hz. During the interval between the target flash and the memory-guided saccade, the “memory period” (1.4 s), subjects either fixated a stationary spot or pursued a spot moving vertically sinusoidally at +/-9 deg at 0.3 Hz. 2. When saccades were made toward the location of targets previously flashed on a stationary background as subjects fixated the stationary spot, median saccadic error was 0.93 deg horizontally and 1.1 deg vertically. These errors were greater than for saccades to visible targets, which had median values of 0.59 deg horizontally and 0.60 deg vertically. 3. When targets were flashed as subjects smoothly pursued a spot that moved vertically across the stationary background, median saccadic error was 1.1 deg horizontally and 1.2 deg vertically, thus being of similar accuracy to when targets were flashed during fixation. In addition, the vertical component of the memory-guided saccade was much more closely correlated with the “spatial error” than with the “retinal error” this indicated that, when programming the saccade, the brain had taken into account eye movements that occurred during the memory period. 4. When saccades were made to targets flashed during attempted fixation of a stationary spot on a horizontally moving background, a condition that produces a weak Duncker-type illusion of horizontal movement of the primary target, median saccadic error increased horizontally to 3.2 deg but was 1.1 deg vertically. 5. When targets were flashed as subjects smoothly pursued a spot that moved vertically on the horizontally moving background, a condition that induces a strong illusion of diagonal target motion, median saccadic error was 4.0 deg horizontally and 1.5 deg vertically; thus the horizontal error was greater than under any other experimental condition. 6. In most trials, the initial saccade to the remembered target was followed by additional saccades while the subject was still in darkness. These secondary saccades, which were executed in the absence of visual feedback, brought the eye closer to the target location. During paradigms involving horizontal background movement, these corrections were more prominent horizontally than vertically. 7. Further measurements were made in two subjects to determine whether inaccuracy of memory-guided saccades, in the horizontal plane, was due to mislocalization at the time that the target flashed, misrepresentation of the trajectory of the pursuit eye movement during the memory period, or both. 8. The magnitude of the saccadic error, both with and without corrections made in darkness, was mislocalized by approximately 30% of the displacement of the background at the time that the target flashed. The magnitude of the saccadic error also was influenced by net movement of the background during the memory period, corresponding to approximately 25% of net background movement for the initial saccade and approximately 13% for the final eye position achieved in darkness. 9. We formulated simple linear models to test specific hypotheses about which combinations of signals best describe the observed saccadic amplitudes. We tested the possibilities that the brain made an accurate memory of target location and a reliable representation of the eye movement during the memory period, or that one or both of these was corrupted by the illusory visual stimulus. Our data were best accounted for by a model in which both the working memory of target location and the internal representation of the horizontal eye movements were corrupted by the illusory visual stimulus. We conclude that extraretinal signals played only a minor role, in comparison with visual estimates of the direction of gaze, in planning eye movements to remembered targ
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IWASAKI, T., and S. KURIMOTO. "No 8 MEASUREMENTS OF VERGENT EYE MOVEMENT BY JUMPING METHOD BEFORE AND AFTER VDT WORK." Acta Ophthalmologica 62, S164 (May 28, 2009): 24a—24. http://dx.doi.org/10.1111/j.1755-3768.1984.tb00645.x.
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Schaub, C. D., C. Tankersley, A. R. Schwartz, P. L. Smith, J. L. Robotham, and C. P. O’Donnell. "Effect of sleep/wake state on arterial blood pressure in genetically identical mice." Journal of Applied Physiology 85, no. 1 (July 1, 1998): 366–71. http://dx.doi.org/10.1152/jappl.1998.85.1.366.
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Genetic determinants may contribute to the large variability in arterial blood pressure responses to changes in sleep/wake state in humans. In this study, we developed techniques to examine the relationship between sleep/wake state and mean arterial pressure (MAP) in unrestrained, genetically identical mice (C57BL/6J; n = 9). The left common carotid artery was catheterized, and arterial blood gases were analyzed 24–48 h postsurgery to verify normal respiratory and metabolic function. The animals were then allowed to cycle naturally through sleep/wake states over a 3- to 4-h period while continuous polysomnography and arterial pressure measurements were made. The MAP decreased from quiet wakefulness to non-rapid-eye-movement sleep (9.8 ± 1.3 mmHg; P < 0.001) and further decreased from non-rapid-eye-movement to rapid-eye-movement sleep (9.7 ± 1.8 mmHg; P < 0.001). We conclude that the inbred strain of C57BL/6J mice exhibits significant and consistent changes in MAP related to sleep/wake state. Future studies can compare responses in this strain of mice with those in other inbred or transgenic mice to determine whether specific genes regulate arterial blood pressure responses to sleep/wake state.
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Paulin, Michael G., Mark E. Nelson, and James M. Bower. "DYNAMICS OF COMPENSATORY EYE MOVEMENT CONTROL: AN OPTIMAL ESTIMATION ANALYSIS OF THE VESTIBULO-OCULAR REFLEX." International Journal of Neural Systems 01, no. 01 (January 1989): 23–29. http://dx.doi.org/10.1142/s0129065789000426.
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Head movements in vertebrates give rise to involuntary eye movements that stabilize visual images on the retina. Previous models of the vestibulo-ocular reflex (VOR), one of the neural mechanisms responsible for stabilizing the eyes during head movements, have assumed that the VOR transfer function should have unity gain and 180° phase shift. Experimental measurements of VOR gain and phase, however, exhibit frequency dependencies that are not easily interpreted within the framework of existing models. We reanalyze the problem of VOR control using stochastic optimal estimation theory and show that VOR dynamics, in general, should differ from the "ideal" unity-gain, 180° phase shift transfer function. We illustrate this approach by computing the optimal VOR transfer function for a simple, second-order dynamical model of a head–neck system. Despite its simplicity, this model is able to give some insight into the dynamical properties of the VOR. In particular, it qualitatively reproduces an experimentally observed gain peak in monkey VOR at high frequencies. The model also predicts that the gain and phase characteristics of the optimal VOR transfer function should depend on the spectrum of natural head movements, possibly giving rise to species-dependent and gait-dependent differences in the VOR transfer function. We suggest that the applicability of optimal estimation extends beyond the control of compensatory eye movements and that it is probably a universal component of movement control in the nervous system.
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Baloh, R. W., K. Beykirch, V. Honrubia, and R. D. Yee. "Eye movements induced by linear acceleration on a parallel swing." Journal of Neurophysiology 60, no. 6 (December 1, 1988): 2000–2013. http://dx.doi.org/10.1152/jn.1988.60.6.2000.
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1. Horizontal and vertical eye movements were induced in normal human subjects by sinusoidal linear acceleration on a parallel swing. The swing frequency was 0.3 Hz and the peak horizontal and vertical acceleration ranged from 0.17 to 0.48 and 0.03 to 0.34 g, respectively. Eye movements were recorded with the scleral search coil technique. 2. With the subjects seated in the dark to stimulate the otolith-ocular reflex, swing displacement along the interaural axis induced horizontal eye movements with a mean sensitivity to translation (ST) (peak eye velocity/peak swing velocity) of 3.8 to 4.7 degrees/m and a mean phase shift (eye velocity re swing velocity) of -152 to -160 degrees. Vertical eye movements had ST and phase values comparable to those of the horizontal eye movements. When the subjects sat facing forward so that the horizontal linear accelerations occurred in the occipitonasal axis, almost identical vertical but no consistent horizontal eye movements were induced. In each case the horizontal and vertical eye movements were proportional to the horizontal and vertical displacement of the swing. 3. With the subject seated in the light looking to an earth-fixed target (synergistic visual-vestibular interaction), the gain (peak eye velocity/peak target velocity) of induced eye movements was near 1, and the phase was compensatory (i.e., approximately -180 degrees) for all stimuli (even at target velocities at which the pursuit gain was less than 1). Subjects were able to suppress the otolith-ocular responses by fixating on a target attached to the swing. The ST decreased by an order of magnitude compared with measurements in the dark without a fixation target. 4. Subjects were able to augment the ST (horizontal and vertical) by imagining an earth-fixed target. Halving the distance of the imagined target approximately doubled the ST. 5. In two of three subjects tested, the ST measured with mental alerting in the dark adaptively increased (approximately doubled) after 20 min of continuous synergistic visual-vestibular interaction. The subject who did not show an adaptive increase in ST began with the highest value of the 10 normal subjects. 6. We conclude that during linear accelerations of the head the otolith signal is correctly interpreted as head movement and not rotation of the gravity vector. The otolith-ocular reflex interacts with the visual pursuit system to improve ocular stability during translational head movements.
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Wallace, CJ, J. Robins, LS Alvord, and JM Walker. "The effect of earplugs on sleep measures during exposure to simulated intensive care unit noise." American Journal of Critical Care 8, no. 4 (July 1, 1999): 210–19. http://dx.doi.org/10.4037/ajcc1999.8.4.210.
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BACKGROUND: Sleep deprivation may contribute to impaired immune function, ventilatory compromise, disrupted thermoregulation, and delirium. Noise levels in intensive care units may be related to disturbed sleep patterns, but noise reduction has not been tested in this setting. OBJECTIVE: To measure the effect of a noise reduction intervention on the sleep of healthy subjects exposed to simulated intensive care unit noise. METHODS: After digital audiotape recording of noise and development of the noise reduction intervention, 5 nocturnal 8-hour periods of sleep were measured in 6 paid, healthy volunteers at 7-day intervals in a sleep disorders center. Polysomnographic data were collected by experienced sleep disorders technicians and scored by certified raters. After the first 3 quiet nights, earplugs were randomly assigned to be worn on the fourth and fifth nights during exposure to the recorded noise. Sound pressure levels were measured during all 5 nights. RESULTS: Sleep architecture and sound measurements on quiet nights did not differ significantly. Sound levels were significantly lower on quiet nights than on noise nights. Exposure to the noise increased the number of awakenings, percentage of stage 2 sleep, and rapid eye movement latency and decreased time asleep, sleep maintenance efficiency index, and percentage of rapid eye movement sleep. Earplugs worn during exposure to the noise produced a significant decrease in rapid eye movement latency and an increase in the percentage of rapid eye movement sleep. CONCLUSION: The results provide a reasonable basis for testing the effects of earplugs on the sleep of critically ill subjects.
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Essig, Peter, Jonas Müller, and Siegfried Wahl. "Parameters of Optokinetic Nystagmus Are Influenced by the Nature of a Visual Stimulus." Applied Sciences 12, no. 23 (November 23, 2022): 11991. http://dx.doi.org/10.3390/app122311991.
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Studies on contrast sensitivity (CS) testing using optokinetic nystagmus (OKN) proposed adjusting the stimulus presentation duration based on its contrast, to increase the time efficiency of such measurement. Furthermore, stimulus-specific limits of the least OKN gain might reduce false negatives in OKN detection procedures. Therefore, we aimed to test the effects of various stimulus characteristics on OKN and to propose the stimulus-specific limits for the OKN gain and stimulus presentation duration. We tested the effect of contrast (C), spatial frequency (SF), and color on selected parameters of robust OKN response, namely its onset and offset time, amplitude, and gain. The right eyes of fifteen emmetropes were tracked with an infrared eye tracker during monocular observations of sinusoidal gratings moving over the horizontal plane with a velocity of (21∘/s). The available contrast levels were C: 0.5%, 2.0%, 8.2%, 16.5%, 33.0%, and 55.5% presented in a random order for ten times in all measurements of SF: 0.12, 0.25, 0.5, and 1.00 cycles per degree and grating type: luminance, red-green, and blue-yellow. This study showed a significant effect of the stimulus characteristics on the OKN onset, offset and gain. The effect of SF was insignificant in OKN amplitude; however, it indicated significance for the C and grating type. Furthermore, the OKN gain and offset limits were proposed as functions of contrast for the luminance and chromatic gratings. This study concludes the characteristics of a visual stimulus have an effect on the OKN gain and onset and offset time, yet do not affect the eye-movement amplitude considerably. Moreover, the proposed limits are expected to improve the time efficiency and eye-movement detection in OKN-based contrast sensitivity measurements.
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Schiavenato, Martin, Meggan Butler-O’Hara, and Paul Scovanner. "Exploring the Association Between Pain Intensity and Facial Display in Term Newborns." Pain Research and Management 16, no. 1 (2011): 10–12. http://dx.doi.org/10.1155/2011/873103.
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BACKGROUND: Facial expression is widely used to judge pain in neonates. However, little is known about the relationship between intensity of the painful stimulus and the nature of the expression in term neonates.OBJECTIVES: To describe differences in the movement of key facial areas between two groups of term neonates experiencing painful stimuli of different intensities.METHODS: Video recordings from two previous studies were used to select study subjects. Four term neonates undergoing circumcision without analgesia were compared with four similar male term neonates undergoing a routine heel stick. Facial movements were measured with a computer using a previously developed ‘point-pair’ system that focuses on movement in areas implicated in neonatal pain expression. Measurements were expressed in pixels, standardized to percentage of individual infant face width.RESULTS: Point pairs measuring eyebrow and eye movement were similar, as was the sum of change across the face (41.15 in the circumcision group versus 40.33 in the heel stick group). Point pair 4 (horizontal change of the mouth) was higher for the heel stick group at 9.09 versus 3.93 for the circumcision group, while point pair 5 (vertical change of the mouth) was higher for the circumcision group (23.32) than for the heel stick group (15.53).CONCLUSION: Little difference was noted in eye and eyebrow movement between pain intensities. The mouth opened wider (vertically) in neonates experiencing the higher pain stimulus. Qualitative differences in neonatal facial expression to pain intensity may exist, and the mouth may be an area in which to detect them. Further study of the generalizability of these findings is needed.
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White, JE, MJ Drinnan, AJ Smithson, CJ Griffiths, and GJ Gibson. "Respiratory muscle activity and oxygenation during sleep in patients with muscle weakness." European Respiratory Journal 8, no. 5 (May 1, 1995): 807–14. http://dx.doi.org/10.1183/09031936.95.08050807.
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Patients with respiratory muscle weakness show nocturnal hypoventilation, with oxygen desaturation particularly during rapid eye movement (REM) sleep, but evidence in individuals with isolated bilateral diaphragmatic paresis (BDP) is conflicting. The effect of sleep on relative activity of the different respiratory muscles of such patients and, consequently, the precise mechanisms causing desaturation have not been clarified. We have studied eight patients, four with generalized muscle weakness and four with isolated BDP during nocturnal sleep with measurements including oxygen saturation and surface electromyographic (EMG) activity of various respiratory muscle groups. Nocturnal oxygenation correlated inversely with postural fall in vital capacity, an index of diaphragmatic strength. During REM sleep, hypopnoea and desaturation occurred particularly during periods of rapid eye movements (phasic REM sleep). In most subjects, such events were "central" in type and associated with marked suppression of intercostal muscle activity, but two subjects had recurrent desaturation due to "obstructive" hypopnoea and/or apnoea. Expiratory activity of the external oblique muscle was present whilst awake and during non-rapid eye movement (NREM) sleep in seven of the eight subjects in the semirecumbent posture. This probably represents an "accessory inspiratory" effect, which aids passive caudal diaphragmatic motion as the abdominal muscles relax at the onset of inspiration. Expiratory abdominal muscle activity was suppressed in phasic REM sleep, suggesting that loss of this "accessory inspiratory" effect may contribute to "central" hypopnoea. We conclude that, in patients with muscle weakness, nocturnal oxygenation correlates with diaphragmatic strength.(ABSTRACT TRUNCATED AT 250 WORDS)
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Amador Campos, J. A., A. Aznar Casanova, J. J. Ortiz Guerra, A. Medina Peña, S. C. Solarte Hurtado, A. Luna Sánchez, J. Illa Girona, and M. D. M. Bernat Martorell. "Assessing distractibility by eye movements in a binocular rivalry task." European Psychiatry 26, S2 (March 2011): 263. http://dx.doi.org/10.1016/s0924-9338(11)71973-3.
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IntroductionAttention deficit hyperactivity disorder (ADHD) is a neurobehavioral disorder, characterized by developmentally inappropriate levels of overactivity, inattention and impulsivity. Measuring inattention is a controversial question in ADHD diagnosis. Eye movement could provide a method to assess distractibility. Several studies have related visual attention and perceptual dominance in binocular rivalry.ObjectivesTo assess visual attention through the measurement of fixations in a binocular rivalry task in ADHD children and control groups.AimsWe proposed a task for the assessment of distractibility and to enhance the diagnosis of attention disorders.MethodsForty children, 20 with ADHD-combined type and 20 controls, matched by gender, age and intelligence, were tested with a binocular rivalry task (i.e. an anaglyph image) with an exogenous distractor appearing regularly. The stimulus was divided in four Areas of Interest (AOI). Measurements of duration of the periods of exclusive dominance, perceptual alternations in dominance / suppression and fixations were taken by an eye tracker and a response box. Analysis of Variance was used to test differences between ADHD and control groups.ResultsSignificant differences between ADHD and control groups were found in dwells at the main AOI. Also, significant differences between groups in “Fixation over alternations ratio” were found.ConclusionsADHD participants looked at the relevant region (AOI_1) for a shorter time than the control group; they also looked at the no demanded regions (AOI_2, AOI_3, AOI_4) longer than the control group. Moreover, the ratio fixations/alternations were greater for the control group than the ADHD group.
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Su, Kuo-Chen, Hong-Ming Cheng, Yu Chu, Fang-Chun Lu, Lung-Hui Tsai, and Ching-Ying Cheng. "Correlating Ocular Physiology and Visual Function with Mild Cognitive Loss in Senior Citizens in Taiwan." Journal of Clinical Medicine 11, no. 9 (May 6, 2022): 2624. http://dx.doi.org/10.3390/jcm11092624.
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The transition of Taiwan from an aging to a super-aging society has come with a cost as more elderly now suffer from cognitive impairment. The main purpose of our study was to investigate if early detection can be developed so that timely intervention can be instituted. We analyzed the correlation of cognitive function with ocular physiology and visual functions between senior citizens aged 60 years or older in Taiwan. Methods: Thirty-six healthy subjects were recruited for the study. Addenbrooke’s cognitive examination III (ACE-III), binocular functions (including objective and subjective refraction, distance and near dissociated phoria, stereopsis, contrast sensitivity, adult developmental eye movement (ADEM), and ocular physiology (by using optical coherence tomography, OCT, and macular pigment measurement, MPS) were performed, and the data were analyzed via independent t-test, chi-square test, Pearson correlation, linear regression, and ROC (receiver operating characteristic) curve. Results: Data analysis showed that (1) patients with poor eye movement had a strong correlation with the total score and all dimensions of cognitive functions, (2) the thickness of the macula had a strong correlation with attention and memory, and (3) patients with poor eye movement and poor stereopsis in combination with thinner inferior macula appeared to have lower cognitive abilities. Discussion and Conclusions: Cognitive dysfunction is not readily identified during the early stage of cognitive decline. The use of simple and inexpensive ADEM or stereopsis test and comparing the OCT results that are popular in optometry clinics for reference can be diagnostic in identifying patients with mild cognitive impairments. With the combined use of macular pigment density or retinal thickness measurements, it was possible to effectively predict the early degradation of cognition.
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Hummel, Gerrit, Saskia Maier, Maren Baumgarten, Cora Eder, Patrick Thomas Strubich, and Nanette Stroebele-Benschop. "Visual attention towards food during unplanned purchases – A pilot study using mobile eye tracking technology." PLOS ONE 16, no. 3 (March 4, 2021): e0247755. http://dx.doi.org/10.1371/journal.pone.0247755.
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This pilot study aims to investigate the relationships between consumers’ weight status, energy density of food and visual attention towards food during unplanned purchase behavior in a real-world environment. After more than a decade of intensive experimental eye tracking research on food perception, this pilot study attempts to link experimental and field research in this area. Shopping trips of participants with different weight status were recorded with mobile eye tracking devices and their unplanned purchase behavior was identified and analyzed. Different eye movement measurements for initial orientation and maintained attention were analyzed. Differences in visual attention caused by energy density of food were found. There was a tendency across all participants to look at low energy density food longer and more often.
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Mansour, Khaled F., James A. Rowley, and M. Safwan Badr. "Measurement of pharyngeal cross-sectional area by finite element analysis." Journal of Applied Physiology 100, no. 1 (January 2006): 294–303. http://dx.doi.org/10.1152/japplphysiol.00364.2005.
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A noninvasive measurement of pharyngeal cross-sectional area (CSA) during sleep would be advantageous for research studies. We hypothesized that CSA could be calculated from the measured pharyngeal pressure and flow by finite element analysis (FEA). The retropalatal airway was visualized by using a fiber-optic scope to obtain the measured CSA (mCSA). Flow was measured with a pneumotachometer, and pharyngeal pressure was measured with a pressure catheter at the palatal rim. FEA was performed as follows: by using a three-dimensional image of the upper airway, a mesh of finite elements was created. Specialized software was used to allow the simultaneous calculation of velocity and area for each element by using the measured pressure and flow. In the development phase, 677 simultaneous measurements of CSA, pressure, and flow from one subject during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep were entered into the software to determine a series of equations, based on the continuity and momentum equations, that could calculate the CSA (cCSA). In the validation phase, the final equations were used to calculate the CSA from 1,767 simultaneous measurements of pressure and flow obtained during wakefulness, NREM, and REM sleep from 14 subjects. In both phases, mCSA and cCSA were compared by Bland-Altman analysis. For development breaths, the mean difference between mCSA and cCSA was 0.0 mm2 (95% CI, −0.1, 0.1 mm2). For NREM validation breaths, the mean difference between mCSA and cCSA was 1.1 mm2 (95% CI 1.3, 1.5 mm2). Pharyngeal CSA can be accurately calculated from measured pharyngeal pressure and flow by FEA.
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Martinez-Conde, Susana, and Stephen L. Macknik. "Unchanging visions: the effects and limitations of ocular stillness." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1718 (February 27, 2017): 20160204. http://dx.doi.org/10.1098/rstb.2016.0204.
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Scientists have pondered the perceptual effects of ocular motion, and those of its counterpart, ocular stillness, for over 200 years. The unremitting ‘trembling of the eye’ that occurs even during gaze fixation was first noted by Jurin in 1738. In 1794, Erasmus Darwin documented that gaze fixation produces perceptual fading, a phenomenon rediscovered in 1804 by Ignaz Paul Vital Troxler. Studies in the twentieth century established that Jurin's ‘eye trembling’ consisted of three main types of ‘fixational’ eye movements, now called microsaccades (or fixational saccades), drifts and tremor. Yet, owing to the constant and minute nature of these motions, the study of their perceptual and physiological consequences has met significant technological challenges. Studies starting in the 1950s and continuing in the present have attempted to study vision during retinal stabilization—a technique that consists on shifting any and all visual stimuli presented to the eye in such a way as to nullify all concurrent eye movements—providing a tantalizing glimpse of vision in the absence of change. No research to date has achieved perfect retinal stabilization, however, and so other work has devised substitute ways to counteract eye motion, such as by studying the perception of afterimages or of the entoptic images formed by retinal vessels, which are completely stable with respect to the eye. Yet other research has taken the alternative tack to control eye motion by behavioural instruction to fix one's gaze or to keep one's gaze still, during concurrent physiological and/or psychophysical measurements. Here, we review the existing data—from historical and contemporary studies that have aimed to nullify or minimize eye motion—on the perceptual and physiological consequences of perfect versus imperfect fixation. We also discuss the accuracy, quality and stability of ocular fixation, and the bottom–up and top–down influences that affect fixation behaviour. This article is part of the themed issue ‘Movement suppression: brain mechanisms for stopping and stillness’.
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Moon, J. K., C. L. Jensen, and N. F. Butte. "Fast-response whole body indirect calorimeters for infants." Journal of Applied Physiology 74, no. 1 (January 1, 1993): 476–84. http://dx.doi.org/10.1152/jappl.1993.74.1.476.
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Portable whole body indirect calorimeters were constructed for full-term (2.5- to 8-kg) and preterm (1- to 2.5-kg) infants. A new calibration system significantly increased the accuracy of flowmeters and gas analyzers. Performance tests with N2 and CO2 infusions and butane combustion demonstrated that the error of individual measurements of O2 consumption and CO2 production were within +/- 2%. The measured error was close to the theoretical uncertainty of approximately +/- 1% calculated from test results of the flowmeters and gas analyzers. System response to a step change in butane combustion rate exceeded 90% within 2 min. Error of +/- 2% and response of 2 min are likely to be the practical lower limits for whole body infant indirect calorimeters with current technology. The calorimeters demonstrated a rapid increase in O2 consumption after feeding (preterm infants) and in the transition from non-rapid-eye-movement to rapid-eye-movement sleep stages (full-term infants).
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Fruzzetti, Lorenzo, Hari Teja Kalidindi, Alberto Antonietti, Cristiano Alessandro, Alice Geminiani, Claudia Casellato, Egidio Falotico, and Egidio D’Angelo. "Dual STDP processes at Purkinje cells contribute to distinct improvements in accuracy and speed of saccadic eye movements." PLOS Computational Biology 18, no. 10 (October 4, 2022): e1010564. http://dx.doi.org/10.1371/journal.pcbi.1010564.
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Saccadic eye-movements play a crucial role in visuo-motor control by allowing rapid foveation onto new targets. However, the neural processes governing saccades adaptation are not fully understood. Saccades, due to the short-time of execution (20–100 ms) and the absence of sensory information for online feedback control, must be controlled in a ballistic manner. Incomplete measurements of the movement trajectory, such as the visual endpoint error, are supposedly used to form internal predictions about the movement kinematics resulting in predictive control. In order to characterize the synaptic and neural circuit mechanisms underlying predictive saccadic control, we have reconstructed the saccadic system in a digital controller embedding a spiking neural network of the cerebellum with spike timing-dependent plasticity (STDP) rules driving parallel fiber—Purkinje cell long-term potentiation and depression (LTP and LTD). This model implements a control policy based on a dual plasticity mechanism, resulting in the identification of the roles of LTP and LTD in regulating the overall quality of saccade kinematics: it turns out that LTD increases the accuracy by decreasing visual error and LTP increases the peak speed. The control policy also required cerebellar PCs to be divided into two subpopulations, characterized by burst or pause responses. To our knowledge, this is the first model that explains in mechanistic terms the visual error and peak speed regulation of ballistic eye movements in forward mode exploiting spike-timing to regulate firing in different populations of the neuronal network. This elementary model of saccades could be extended and applied to other more complex cases in which single jerks are concatenated to compose articulated and coordinated movements.
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Choi, H. S., D. U. Jung, D. W. Jeon, S. J. Kim, and J. J. Moon. "Evaluation of the Correlation between Gaze Avoidance and Schizophrenia Psychopathology with Deep Learning-based Emotional Recognition." European Psychiatry 65, S1 (June 2022): S315. http://dx.doi.org/10.1192/j.eurpsy.2022.803.
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Introduction Direct gaze is the most important mediator of social interaction and communication. Existing studies have evaluated eye movements of patients with schizophrenia by presenting stimuli using photographs or pre-recorded videos, but few directly investigated gaze avoidance in real-world situations. Objectives To investigate the correlation between gaze avoidance and psychopathology in patients with schizophrenia through eye movement measurements in real-life interpersonal situations. Methods We enrolled 52 clinically stable patients with schizophrenia. Psychopathology was evaluated using the Positive and Negative Syndrome Scale (PANSS), Hamilton Depression Rating Scale, and Hamilton Anxiety Rating Scale. After presenting a visual stimulus, eye movements were measured with Tobii Pro Wearable Glasses 2, and deep learning-based emotional recognition using the residual masking network was used for neutral stimulus verification. Statistical analyses were performed using Pearson’s correlation and regression analyses. Results Data of 45 participants with verified stimulus neutrality by deep learning image recognition were used for analysis. The first dwelling time was negatively correlated with the PANSS positive syndrome subscale (p=0.028), general psychopathology subscale (p=0.008), total score (p=0.008), 5-factor positive symptoms (p=0.035), and 5-factor depression/anxiety symptoms (p=0.008). The baseline-area of interest (AOI) pupil diameter change was positively correlated with PANSS 5-factor positive symptom scores (p=0.039). After adjusting for additional variables, the same items had a significant effect on the first dwelling time and baseline-AOI pupil diameter change. Conclusions Psychopathology, particularly positive symptoms, was associated with gaze avoidance and pupil diameter in patients with schizophrenia. Evaluating the characteristics of eye movements in patients with schizophrenia will enable better understanding of their symptoms. Disclosure No significant relationships.
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Mehrabi, Elaheh. "Physiological Measurements of Vigilance: A Systematic Review." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 66, no. 1 (September 2022): 823–27. http://dx.doi.org/10.1177/1071181322661512.
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Vigilance is the ability to sustain attention for more than 5 to 10 minutes at a time. Maintaining vigilance over a prolonged duration is challenging, and the ability to do so generally declines over time; This is a phenomenon that is known as “vigilance decrement.” Vigilance decrement is often associated with physiological changes. Although previous studies have examined the relationship between physiological responses and vigilance decrement, the results are inconsistent and the trends are not sufficiently clear. Recognizing the need for a comprehensive overview of the existing results, in this paper, we review the most recent studies focusing on physiological changes as indicators of vigilance decrement. We consider electroencephalography (EEG), electrocardiography (ECG), eye movement, and electromyography (EMG). We present an overview of the overall relationship between these measures and vigilance levels; we also highlight the limitations and challenges of previous studies and provide some insight into future research directions in this field.
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Guillemant, P., E. Ulmer, and G. Freyss. "3-D Eye Movement Measurements on Four Comex's Divers Using Video CCD Cameras, during High Pressure Diving." Acta Oto-Laryngologica 115, sup520 (January 1995): 288–92. http://dx.doi.org/10.3109/00016489509125251.
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Przybyszewski, A., S. Szlufik, J. Dutkiewicz, P. Habela, and D. Koziorowski. "Eye Movement (EM) measurements as objective and precise biomarker for symptoms development in patients with Parkinson's disease." Journal of the Neurological Sciences 357 (October 2015): e283-e284. http://dx.doi.org/10.1016/j.jns.2015.08.990.
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Santos-Paz, Jose Angel, Álvaro Sánchez-Picot, Ana Rojo, Aitor Martín-Pintado-Zugasti, Abraham Otero, and Rodrigo Garcia-Carmona. "A novel virtual reality application for autonomous assessment of cervical range of motion: development and reliability study." PeerJ 10 (September 14, 2022): e14031. http://dx.doi.org/10.7717/peerj.14031.
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Background Neck pain, one of the most common musculoskeletal diseases, affects 222 million people worldwide. The cervical range of motion (CROM) is a tool used to assess the neck’s state across three movement axes: flexo-extension, rotation, and lateral flexion. People with neck pain often have a reduced CROM, and they feel pain at the end-range and/or accompany neck movements with compensatory trunk movements. Virtual reality (VR) setups can track the movement of the head and other body parts in order to create the sensation of immersion in the virtual environment. Using this tracking position information, a CROM assessment can be performed using a VR setup that may be carried out autonomously from the user’s home. The objectives of this study were to develop a VR experience that could be used to perform a CROM assessment, and to evaluate the intra-rater and inter-rater reliability of the CROM measures guided by this VR experience. To the best of our knowledge, a study of this type has not been carried out before. Materials & Methods A total of 30 asymptomatic adults were assessed using a VR device (HTC Vive Pro Eye™). Two raters provided support with the VR setup, and the participants were guided by the VR experience as they performed the movements. Each rater tested each subject twice, in random order. In addition to a head-mounted display (HMD), a tracker located on the subject’s back was used to measure trunk compensatory movements. The CROM was estimated using only the HMD position and this measurement was corrected using the tracker data. The mean and standard deviation were calculated to characterize the CROM. To evaluate the reliability, the interclass correlation coefficients (ICC) were calculated for intra-rater and inter-rater analysis. The standard error of measurement and minimum detectable change were also calculated. The usability of the VR system was measured using the Spanish version of the System Usability Scale. Results The mean CROM values in each axis of movement were compatible with those described in the literature. ICC values ranged between 0.86 and 0.96 in the intra-rater analysis and between 0.83 and 0.97 in the inter-rater analysis; these values were between good and excellent. When applying the correction of the trunk movements, both the intra-rater and inter-rater ICC values slightly worsened except in the case of the lateral flexion movement, where they slightly improved. The usability score of the CROM assessment/VR system was 86 points, which is an excellent usability score. Conclusion The reliability of the measurements and the usability of the system indicate that a VR setup can be used to assess CROM. The reliability of the VR setup can be affected by slippage of the HMD or tracker. Both slippage errors are additive, i.e., only when the sum of these two errors is less than the compensatory movement do the measurements improve when considering the tracker data.
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Sipos, László, Attila Gere, Zoltán Kókai, Ákos Nyitrai, Sándor Kovács, Ágnes Urbin, Krisztián Samu, and Klára Wenzel. "Eye-Tracker Analysis of the Contrast Sensitivity of Anomalous and Normal Trichromats: A Loglinear Examination with Landolt-C Figures." Applied Sciences 11, no. 7 (April 2, 2021): 3200. http://dx.doi.org/10.3390/app11073200.
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The contrast sensitivity of normal and anomalous trichromats were examined with Landolt-C figures by eye-tracking system. For the measurements, two series of test images (achromatic and colored) were designed. The difficulty levels of the tests were gradually increased after each right answer. In the case of the observation of the ring of the Landolt-C figures, the variables related to fixation duration, fixation count, visit duration and count significantly affected this subject, success or image parameters, and their interactions. The main questions of this study were as follows: Which statistical method is suitable to model the differences between anomalous and normal trichromats? Which eye-movement variables have a significant effect on the investigated parameters and on their interactions? Is there any significant difference between eye-movement variables of normal and anomalous trichromats? How does the survival time of anomalous and normal trichromats change in the case of achromatic and colored figures? The results showed that the right answers of anomalous and normal trichromats can be described with multiple or cross-classified contingency tables evaluated effectively by loglinear regression. The survival analysis showed that normal trichromats are more successful in interpreting colored images, while anomalous trichromats seemed to be more efficient in perceiving achromatic images.
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Jaschinski, Wolfgang. "Warum das Testen der Vergenz so kompliziert ist - Die subjektive und die objektive Fixationsdisparität." Optometry & Contact Lenses 2, no. 4 (April 28, 2022): 128–34. http://dx.doi.org/10.54352/dozv.umhv5676.
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Purpose. This review article describes recent findings of eye movement research of ocular vergence and provides an in- terpretation regarding those aspects of binocular vision that are assessed by clinical nonius tests. Material and Methods. In the clinical practice of binocular testing, different types of nonius tests are traditionally used for the vergence position of the eyes: near to a fusion stim- ulus, the test includes monocularly presented nonius lines; the perceived nonius offset is understood as a measure of “subjective fixation disparity”. However, in basic research precise eye movement recording systems are applied since the 1980s for measuring the “objective fixation disparity”. Results. The correlation between subjective and objective measures of fixation disparity tends to be low. Subjective measures are typically much smaller than objective measures. Conclusion. A precise terminology for the results of these measurements allows one to describe the physiological dif- ferences between the two aspects of fixation disparity. Recent research findings may be the basis for reconsidering the mechanisms of motor and sensory fusion and interpreting the clinical findings accordingly. With the help of video eye track- ers, it is now possible to conduct clinically-oriented optom- etric research of subjective and objective fixation disparity. Keywords Binocular vision, fixation disparity, vergence, fusion
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Vortmann, Lisa-Marie, and Felix Putze. "Combining Implicit and Explicit Feature Extraction for Eye Tracking: Attention Classification Using a Heterogeneous Input." Sensors 21, no. 24 (December 8, 2021): 8205. http://dx.doi.org/10.3390/s21248205.
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Statistical measurements of eye movement-specific properties, such as fixations, saccades, blinks, or pupil dilation, are frequently utilized as input features for machine learning algorithms applied to eye tracking recordings. These characteristics are intended to be interpretable aspects of eye gazing behavior. However, prior research has demonstrated that when trained on implicit representations of raw eye tracking data, neural networks outperform these traditional techniques. To leverage the strengths and information of both feature sets, we integrated implicit and explicit eye tracking features in one classification approach in this work. A neural network was adapted to process the heterogeneous input and predict the internally and externally directed attention of 154 participants. We compared the accuracies reached by the implicit and combined features for different window lengths and evaluated the approaches in terms of person- and task-independence. The results indicate that combining implicit and explicit feature extraction techniques for eye tracking data improves classification results for attentional state detection significantly. The attentional state was correctly classified during new tasks with an accuracy better than chance, and person-independent classification even outperformed person-dependently trained classifiers for some settings. For future experiments and applications that require eye tracking data classification, we suggest to consider implicit data representation in addition to interpretable explicit features.
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Wang, Kehao, Ziyan Qiu, Yiping Xie, Shuo Cai, Yang Zhao, Barbara K. Pierscionek, Jiangzhen Guo, and Yubo Fan. "Design of an Automatically Controlled Multi-Axis Stretching Device for Mechanical Evaluations of the Anterior Eye Segment." Bioengineering 10, no. 2 (January 20, 2023): 142. http://dx.doi.org/10.3390/bioengineering10020142.
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The young eye has an accommodative ability involving lens shape changes to focus over different distances. This function gradually decreases with age, resulting in presbyopia. Greater insights into the mechanical properties of anterior eye structures can improve understanding of the causes of presbyopia. The present study aims to develop a multi-axis stretching device for evaluating the mechanical properties of the intact eye lens. A stretching device integrating the mechanical stretcher, motor, torque sensor and data transmission mechanism was designed and developed by 3D printing. The mechanical stretcher can convert rotation into radial movement, both at constant speeds, according to the spiral of Archimedes. The loading unit equipped with eight jaws can hold the eye sample tightly. The developed device was validated with a spring of known constant and was further tested with anterior porcine eye segments. The validation experiment using the spring resulted in stiffness values close to the theoretical spring constant. Findings from measurements with porcine eye samples indicated that the measured forces are within the ranges reported in the literature. The developed multi-axis stretching device has good repeatability during experiments with similar settings and can be reliably used for mechanical evaluations of the intact eye lens.
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Krouse, Helene J., Jean E. Davis, and John H. Krouse. "Immune Mediators in Allergic Rhinitis and Sleep." Otolaryngology–Head and Neck Surgery 126, no. 6 (June 2002): 607–13. http://dx.doi.org/10.1067/mhn.2002.125300.
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OBJECTIVE: Our study goal was to examine polysomnography, indices of sleep and allergy, and serum and nasal cytokines in allergic and nonallergic subjects. STUDY DESIGN AND SETTING: In this descriptive, exploratory study, 4 allergic and 4 nonallergic subjects underwent 2 nights of polysomnographic recording with serial measurements of cytokines and completed measures of sleep quality and allergic symptoms. RESULTS: Three serum cytokines (interleukin (IL)-1β, IL-4, and IL-10) were higher in allergic subjects and were termed proallergic. Three serum cytokines (IL-1ra, IL-2, and IL-12) were higher in nonallergic subjects and were termed allergy inhibitory. Proallergic serum cytokines correlated with increased latency to rapid eye movement sleep, decreased time in rapid eye movement sleep, and decreased latency to sleep onset. Low levels of allergy-inhibitory serum cytokines were associated with increased allergic symptoms. CONCLUSIONS: Differences in serum cytokines between allergic and nonallergic individuals are associated with variations in polysomnography and allergic symptoms. SIGNIFICANCE: Understanding these mechanisms may suggest novel approaches to alleviating drowsiness and other symptoms in allergic patients.
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Martín, Jesús Morenas, Vicente Luis del Campo, and Luis Jesús Manso Fernández-Argüelles. "Design and development of a low-cost mask-type eye tracker to collect quality fixation measurements in the sport domain." Proceedings of the Institution of Mechanical Engineers, Part P: Journal of Sports Engineering and Technology 233, no. 1 (November 9, 2018): 116–25. http://dx.doi.org/10.1177/1754337118808177.
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The aim of the study was to build a low-cost mask-type eye tracker with accuracy and precision levels similar to those reported for commercial eye tracking devices. To this end, head-mounted hardware was designed and developed, while open-source software was modified for digital image capture, manipulation, and fixation analysis. An image recognition application was also included with different lighting scenarios. Moreover, parallax and viewing perspective errors were controlled to ensure the quality of data collection. The device was wireless and lightweight (99 g) to allow for natural movement and avoid participant discomfort. After calibration of a 9-target monocular grid, spatial accuracy and precision of the eye tracker was evaluated by 30 participants, at four different lighting setups, both before and after a climbing task. Validity tests showed high levels of accuracy in all conditions as evidenced by a systematic error for a 13-target grid of <0.5°. The reliability tests also showed consistent measurements with no differences in accuracy recorded between participants, lighting conditions, and visual behaviors for the pre- versus post-climbing task. These results suggest that the present eye tracker reports spatial accuracy similar to other commercial systems with levels of high quality. Altogether, this innovative user interface is suitable for research purposes and/or performance analysis in physical activity and sport-related activities. Also, features of this mask-type eye tracking system make it a suitable perceptual user interface to investigate human–computer interactions in a large number of other research fields including psychology, education, marketing, transportation, and medicine.
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Li, Xiaomeng, Andry Rakotonirainy, Xuedong Yan, and Yuting Zhang. "Driver’s Visual Performance in Rear-End Collision Avoidance Process under the Influence of Cell Phone Use." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 37 (June 30, 2018): 55–63. http://dx.doi.org/10.1177/0361198118782758.
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Rear-end crash is the most common type of on-road traffic crash, and cell phone use contributes to the increase of rear-end crashes. The effects of cell phone use on driving performance have been thoroughly investigated in previous research with various measurements. However, change in driver’s visual performance while using a cell phone in situations with high rear-end risk has not yet been fully understood. This driving simulator study investigated drivers’ eye movement performance in a rear-end collision avoidance maneuver during cell phone conversation. Eye movement data of 36 participants were collected in a car-following scenario featuring imminent rear-end collision. The whole collision avoidance process was divided into four stages for eye movement data analysis, including normal driving stage, brake response stage, deceleration adjusting stage, and speed recovering stage. Results showed that the average pupil size, fixation duration, and dwell time on the leading vehicle increased significantly during the brake response and deceleration adjusting stages. This indicated that the drivers’ cognitive workload increased during these stages. Drivers used blink inhibition and quick saccade as a visual compensation strategy to mitigate the increased workload from cell phone use during the brake response stage. However, in the deceleration adjusting stage, the cell phone use condition led to a lower fixation frequency on the leading vehicle than in the no phone use condition. Professional drivers were found to pay more visual attention to the leading vehicle than non-professional drivers in the normal driving stage.
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Ge, Jingjie, Ping Wu, Shichun Peng, Huan Yu, Huiwei Zhang, Yihui Guan, David Eidelberg, Chuantao Zuo, Yilong Ma, and Jian Wang. "Assessing Cerebral Glucose Metabolism in Patients with Idiopathic Rapid Eye Movement Sleep Behavior Disorder." Journal of Cerebral Blood Flow & Metabolism 35, no. 12 (July 29, 2015): 2062–69. http://dx.doi.org/10.1038/jcbfm.2015.173.
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Idiopathic rapid eye movement sleep behavior disorder (RBD) is a risk marker for subsequent development of neurodegenerative parkinsonism. In this study, we aimed to investigate whether regional cerebral metabolism is altered in patients with RBD and whether regional metabolic activities are associated with clinical measurements in individual patients. Twenty-one patients with polysomnogram-confirmed RBD and 21 age-matched healthy controls were recruited to undertake positron emission tomography imaging with [18F]fluorodeoxyglucose. Differences in normalized regional metabolism and correlations between metabolic activity and clinical indices in RBD patients were evaluated on a voxel basis using statistic parametric mapping analysis. Compared with controls, patients with RBD showed increased metabolism in the hippocampus/parahippocampus, cingulate, supplementary motor area, and pons, but decreased metabolism in the occipital cortex/lingual gyrus ( P < 0.001). RBD duration correlated with metabolism positively in the anterior vermis ( r=0.55, P = 0.01), but negatively in the medial frontal gyrus ( r=-0.59, P = 0.005). In addition, chin electromyographic activity presented a positive metabolic correlation in the hippocampus/parahippocampus ( r=0.48, P = 0.02), but a negative metabolic correlation in the posterior cingulate ( r=-0.61, P = 0.002). This study has suggested that region-specific metabolic abnormalities exist in RBD patients and regional metabolic activities are associated with clinical measures such as RBD duration and chin electromyographic activity.