Fig 1.
Illustration of stimulus setup and procedure.
(a) The display was viewed through a mirror stereoscope. The gray squares were constantly presented to ensure binocular fusion. (b) Example of a trial sequence, here with a target presented to the right eye, and a mask to the left eye, both above the fixation point. Negative SOAs refer to trials where the mask preceded the target. (c) Illustration of the assignment of keys to perceived target contrast. The same figure (with German labels) was part of the on-screen instruction.
Table 1.
Individual Fit results–Main Experiment.
Fig 2.
Normalized visibility ratings as a function of SOA, averaged across target presentation side (above or below fixation) and across control subjects (a) or patients (b). The gray lines in panel a) depict the monoptic conditions where targets and masks were presented to the same eye. These conditions were only used in the control group. The colored lines (blue for the control group, red for the patients group) depict the dichoptic conditions, where targets and masks were presented to different eyes. For the control groups we differentiate between the left and red eye whereas for the patients we differentiate between the ON-affected and unaffected eye. Negative SOAs refer to trials in which masks preceded targets, positive SOAs to trials with targets preceding masks. For the purpose of illustration only, the depicted functions were fitted to the visibility ratings after averaging across subjects / patients. All statistical analyses were based on individually fitted functions.
Fig 3.
Average SOAmax (ms) for the control group (N = 8) and the patients (N = 6), depending on the eye to which the target was presented.
The mask was always presented to the opposite eye. Error bars depict the 95% confidence interval of the mean. Each connected pair of circles represents SOAmax-values from a single subject / patient.
Fig 4.
Stimuli used in the control experiment.
Stimuli depicted in a) and b) are identical to the stimuli used in the main experiment. Stimuli depicted in c) and d) were created by blurring the contours with a Gaussian kernel while keeping overall stimulus energy (i.e. the average brightness of the display) constant.
Fig 5.
Normalized visibility ratings observed in the control experiment as a function of SOA for four subjects.
The control experiment featured only dichoptic conditions, in which targets and masks were presented to different eyes. The two subjects depicted in the left half of the figure, the left eye received blurred stimuli to mimic loss of visual acuity. The two subjects depicted on the right, the right eye received blurred stimuli. The bar charts show the temporal position of the individual minima (SOAmax).
Table 2.
Individual Fit results–Control Experiment.