Computer software was purpose written to pre-process the data, co-register it to the film clips and to quantify eye movements and point-of-regard (using a dynamic bivariate contour ellipse analysis).
The saccades are corrective, serving to bring the fixation axis on the point of regard after this has drifted away from it too far, and thus are a manifestation of the fixation reflex.
We examined six configurations which differed in the presence or absence of DOF blur and the value of the ICD: fixed and equal to the anatomical interpupillary distance, fixed and chosen by the participant, or variable, depending on the depth of the viewer's point of regard (POR).
To quantify the spatial coincidence of the point of regard location for all the control subjects, we calculated the best-fit bivariate contour ellipse (BCE).
This is particularly striking when the individual binocular visual field defects, made dynamic by aligning them to the moving point of regard, are superimposed on the films.
In addition, observers' eye movements were carefully monitored on a series of video screens, which showed the observers' point of regard superimposed on a view of the stimulus, as well as a direct view of the observers' eye.
It would, for example, be useful to know if glaucoma patients exhibit the same eye movement behaviour as healthy subjects, or maintain the same point of regard when looking at, or interpreting, an everyday scene.
In this video the blue symbol indicates the point of regard for the patient and the red symbols represent the point of regard for a random sample of the controls.
