Showing papers on "Eye tracking published in 1976"
TL;DR: This paper presented a theoretical account of the sequence and duration of eye fixation during simple cognitive tasks, such as mental rotation, sentence verification, and quantitative comparison, and linked the eye fixation behavior to a processing model for the task by assuming that the eye fixates the referent of the symbol being operated on.
1,499 citations
TL;DR: It is argued that eye movements in reading are under momentary, non-random control and models attempting to account for eye movement data on a random basis, or by simple gain controls or visual buffer monitoring are found acceptable.
473 citations
TL;DR: Analysis of the eye movement characteristics suggested that the main input to the smooth pursuit system was derived, in a non-graded way, from the position detector activation of the target-moving structure.
Abstract: Smooth pursuit eye movements have been described as resulting from the tracking of self-moved targets in total darkness. This study investigated the nature of the signal responsible for the release of smooth pursuit in this particular situation. Simultaneous monitoring of eye and hand positions shows that in total darkness smooth pursuit can only be released if the imagined target is either passively or actively moved by the subject's hand. An ischaemic block applied at the level of the biceps allowed us to selectively remove the afferent signal preferentially to the efferent copy in tasks involving eye tracking of an imaginary target actively or passively moved. The results show that an afferent signal was necessary and sufficient to release smooth pursuit, whereas the efferent copy alone could not trigger smooth pursuit. However, the efferent copy could play an important role in the phase relationship (prediction) between eye and finger events and in the activation of the concomitantly active saccadic system. Analysis of the eye movement characteristics, in various non-visually guided, load-affected situations, suggested that the main input to the smooth pursuit system was derived, in a non-graded way, from the position detector activation of the target-moving structure.
102 citations
TL;DR: In three experiments, targets and masking stimuli were briefly flashce while observers visually tracked a moving dot and visual masking during pursuit eye movements depended on the apparent position of the stimuli, not their retinal positions as such, which is in disagreement with previous studies of visual masks during saccadic eye movements.
Abstract: In three experiments, targets and masking stimuli were briefly flashce while observers visually tracked a moving dot. Masking stimuli were more effective when they appeared to be in the same place as the target but stimulated different parts of the retina than when they stimulated the same parts of the retina but appeared displaced because of of an intervening pursuit eye movement. Visual masking during pursuit eye movements thus depended on the apparent position of the stimuli, not their retinal positions as such, which is in disagreement with previous studies of visual masking during saccadic eye movements. The apparent conflict can be explained in terms of the functional significance of visual masking in tracking and saccardic movements: Retinal position masking after saccadic eye movements may erase previous images, and apparent position masking during pursuit eye movements may make moving targets more visible. Language: en
87 citations
TL;DR: It appears, then, that the specification of innervation to the extraocular muscles for smooth tracking is predominantly peripheral, i.e. it occurs beyond the stage in the efferent command process monitored by perception.
76 citations
TL;DR: The reading records showed a wide variety of behavior: 1 patient performed normal reading movements, 1 “ slow reader” manifested an excessive number of fixations as well as extended fixational durations, another “slow reader’ only exhibited ancessive number offixations, a patient with dyslexia performed backward reading movements and 1 patient exhibited nystagmus superimposed upon the reading pattern.
Abstract: Since the time of Javal, it has been well established that normal reading eye movement patterns have 3 principal components: (1) small saccades that move the eyes from word to word, (2) large saccades that return the eyes to the beginning of the next line, and (3) fixation pauses between eac
69 citations
01 Jan 1976
TL;DR: The paper outlines the plans and progress related to the development of a Programmed Eye-track Recording System and Eye-coupled Ubiquitous Scene-generator known by the acronym PERSEUS and discusses automatic detection of fixations and saccades, automatic scanpath analysis, fixation-conditional stimulation, and digital scene generation.
Abstract: The paper outlines the plans and progress related to the development of a Programmed Eye-track Recording System and Eye-coupled Ubiquitous Scene-generator known by the acronym PERSEUS. Particular attention is given to the design and implementation of a computer-based real-time eye-tracking system with associated digital scenic display capability. The accurate eye-tracker developed by Cornsweet and Crane (1973) is selected for this purpose. The discussion covers automatic detection of fixations and saccades, automatic scanpath analysis, fixation-conditional stimulation, and digital scene generation. The all-digital approach to scenic simulation not only eliminates the camera optics and electromechanical servomechanisms of TV-model systems of simulation but also opens the way to the virtually unlimited sequencing of data-base contents and perspectives thereof.
49 citations
Journal Article•
TL;DR: An algorithm for digital computer analyses of electro-oculographically recorded saccardic eye movements provides a sensitive functional test of the extra-ocular muscles and their brain control system.
Abstract: An algorithm for digital computer analyses of electro-oculographically recorded saccardic eye movements is presented. From a brief, 4-min recording session detailed statistical information about saccade velocity, accuracy, and delay time can be obtained. Since this data is not significantly altered by practice of motivational factors, it provides a sensitive functional test of the extra-ocular muscles and their brain control system.
35 citations
TL;DR: Observations were made of the dynamics of the eye and head during an ‘element’ of visual search, defined as the coordinated sequence of movements beginning with the signal to refixate and ending with target discrimination and response.
Abstract: Measurements were made of the dynamics of the eye and head during an ‘element’ of visual search, defined as the coordinated sequence of movements beginning with the signal to refixate and ending with target discrimination and response. Independent variables wore target angle, 20 to 100 degrees, certainty in target location, target brightness, target information content, and alcohol stress. Dependent performance measures included reaction times of the eye and head, number of eye movements, maximum head velocity, time to acquire target, and response time, as well as qualitative descriptions of the movement patterns.
27 citations
01 Aug 1976
TL;DR: In this article, a mechanism of partial visual tracking to account for the viewing distance dependency of visual performance in vibration was criticized because ocular resonance was not considered, and it was shown that the major component of the eye movement is rotational rather than translational.
Abstract: : A hypothetical mechanism of partial visual tracking to account for the viewing distance dependency of visual performance in vibration was criticized because ocular resonance was not considered. By means of mechanical and photographic techniques, the resonant frequency of the eye was found to be 18 Hz; however, the amplification factor is insufficient to account for the observed performance. Additional psychophysical tests were not inconsistent with original hypothesis, and also demonstrate that the major component of the eye movement is rotational rather than translational.
TL;DR: The results of all three experiments indicate that the accuracy of shape perception improves with age under aperture-viewing conditions, and the conditions in which eye movements were required to pick up shape information led to an improvement in the processing of the shape information.
TL;DR: A model for the extraocular plant of the human visual eye tracking mechanisms is discussed and its sensitivity to variation of controller signal nervous activity is studied in order to determine the type of activity that yields realistic simulations characteristic of typical saccadic eye movements.
01 Oct 1976
TL;DR: Subjects were required, on command, to shift their attention from an ongoing manual control task to a peripheral monitor displaying digital information for a discrete processing task.
Abstract: : Subjects were required, on command, to shift their attention from an ongoing manual control task to a peripheral monitor displaying digital information for a discrete processing task. Measurements were made of eye and head dynamics during the visual search and processing tasks. The independent variables of monitor angle, monitor discriminability, certainty of monitor location, processing task complexity and the subjects' tracking task performance status at the time of the visual search command were examined for possible effects on the visual search patterns. Dependent performance measures included the reaction times of the eye and head, the time to acquire the monitor and the pattern of saccadic eye movements during this period, the time of fixation on the monitor, the time required for the processing task, and the time to reacquire the control task.
TL;DR: The results indicate that the eye movement produced by the vestibulo-oculomotor system is a predictive and supplemental movement which does not coincide with displacement of visual objects.
Abstract: In order to explain physiological function of the vestibulo-ocular system, transfer function (TF)of the oculomotor system was studied in 5 healthy male subjects. For this purpose, the following three tests were pezformed, that is, eye tracking test(ETT) and pendular rotation tests(PRT)in the dark and light were respectively performed in order to examine the opto-oculomotor, vestibulo-oculomotor and optovestibulo-oculomotor system.The target movement and eye movement in the ETT, or the skull's angular displacement and acceleration and the eye movement in the PRT were simultaneously recorded with a polygraph and a data-recorder. From the recordings of the data-recorder, the TF was calculated using a specially designed program with PDP-12 computer, namely, the TF of the oculooculomotor system was calculated with regard to the target movement as input and the eye movement as output. From the record obtained by the PRT in the dark and light, the TF of the vestibulo-oculomotor system and the optovestibulo-oculomotor system were respectively calculated for the skull's angular displacement as input and the eye movement as output. The reason for using the skull's angular displacement as input is that the interrelationship between the head displacement and the eye movement directly indicates the vestibulo-oculomotor function which is to stabilize the retinal image during head movement. The results computed were displayed as a Bode plots(gain and phase diagram)on a cathode ray tube of the PDP-12. The results obtained were as follows.(1) The opto-oculomotor system performs a proportional control in eye tracking to visual object with pendular motion from 0.4 to 1.0 Hz.(2) The vestibulo-oculomotor system performs a derivative control in inducing the eye movement to the skull's displacement This results indicate that the eye movement produced by the vestibulo-oculomotor system is a predictive and supplemental movement which does not coincide with displacement of visual objects. And, it plays an important role in visual fixation during short, rapid head movement.(3) The optovestibulo-oculomotor system performs a proportional control by making the eye movement correspond to the skull's displacement during head movement from o.3 to 1.5Hz.The result indicates the capability of maintaining visual fixation to external objects through the collaboration of the eye and labyrinth. Furthermore, the result shows that the vestibulo-oculomotor system plays an active part in visual fixation during head movement with periodic motion exceeding 1.0Hz.