Showing papers on "Eye tracking published in 1972"

Eye Movements and Perceived Visual Direction

Abstract: The implicit assumption that visual perception is not susceptible to influences from extraretinal sources1 has held extremely well in the areas of color vision, contour perception, and intensity discrimination. It has permitted the development of theoretical models of considerable generality for treatment of psychophysical phenomena in these areas that are based essentially on reasonable inferences from present knowledge regarding the neurophysiology, photochemistry, and neuroanatomy of the primary visual projection system. As will be indicated below, where this assumption can be reasonably made in the area of space perception some progress has taken place in a search for physiologically-based theoretical mechanisms for treatment of psychophysical data.

Are the Eye Movements of Dreaming Sleep Related to the Visual Images of the Dreams

Abstract: As a result of recording eye movements during Stage REM sleep by AC electrooculography (EOG) previous investigators concluded that each eye movement is the response to the visual action in each dream. When we repeated the study using DC EOG it was discovered that only a minority of eye movements during Stage REM are in the direction of the visual action in the dream. If only single, large amplitude, prominent eye movements are considered then most such movements are related to colorful, compelling visual action occurring as a prominent single visual action against a quiet background. The AC recording method used in past studies emphasizes these isolated movements; perhaps this explains the disparity in results. At any rate, most eye movements during REM sleep are unrelated to the action in the dream. When these eye movements were analyzed in regard to the direction of movements, sequential order of movements, and randomness in time, we found that similar patterns of oculomotor output were found in all subjects. Thus, the nervous system executes a patterned output of oculomotor activity during dreaming sleep which is fairly consistent in all subjects. At times, however, a link is established between the visual and oculomotor systems and the eyes respond to visual action.

Two dimensional eye tracker and method for tracking an eye

Abstract: An eye tracker for continuously tracking orientation of the optic axis of an eye in which the eye is flooded with light so that Purkinje images are formed. Two of the Purkinje images are deflected so as to incident on photodetectors. The eye tracker includes optic means for forming an image of the eye with input and output optics arranged to operate on the image of the eye rather than the eye itself. A relatively small two-dimensionally pivoted mirror is disposed at the center of rotation of the image of the eye so as to have fast response to rotation movements of the eye. Further, servo means are provided for moving split-field photodetectors on which the first and fourth Purkinje images are incident. Tracking the position of the Purkinje images through the photocells gives an indication of the orientation of the optic axis of the eye.

The Measurement of Eye Behavior: Critical and Selected Reviews of Voluntary Eye Movement and Blinking.

Abstract: : VOUS SYSTEM, PSYCHOTROPIC AGENTS*OCULOMETERS, PUPILLOMETRY, *EYE MOVEMENTSThe review covers recent research on eye movements and blinking. The eye movement portion of the report describes the various types of eye movement, the problems of measurement, and the techniques available to measure these eye movements. Some of the more advanced oculometers are described and the need for data processing and adequate data reduction technique is emphasized. In the section covering dependent variable and performance measures, a list of direct and derived measures is provided which covers scan paths, fixations, eye blinks, and changes in pupil size. The section on blinking contains a critical and selected review of articles in this area. The physiology of blinking is reviewed and experiments dealing with normal blink rate and theories of blinking are discussed. (Author)

Experimental study of visual accommodation

Abstract: A summary report of a research effort related to the human visual accommodation system is presented. A theoretical study of the accommodation system was made. Subsequent effort was aimed at the development of specialized instrumentation for experiments designed to lead to understanding the nature of the control system in human accommodation. The necessary instrumentation consisted primarily of: (1) an automatic optometer to measure the state of eye focus, (2) a focus stimulator device to control the apparent optical distance to any target, and (3) a two-dimensional eye tracker. The concepts and designs of the first two instruments have been published in the open literature, but this report contains the first detailed treatment of the Purkinje eye tracker developed under this program. The report also discusses an accommodation lag model to explain the ability of the eye to apparently know the polarity of focus error even though the blur on the retina is to a first-approximation an even function. The interaction of the accommodation and eye movement systems is also discussed, as is the ability to train the visual accommodation system to a surprisingly responsive condition in only a few hours of training.