Subject(s)
Form Perception/physiology , Pattern Recognition, Visual/physiology , Retina/physiology , Humans , Male , Rotation , Visual AcuityABSTRACT
Flicker tresholds have been measured with intermittent stimuli as a function of the presentation time of the stimulus. The periods of flickering light were separated by 1-s dark intervals. Under these conditions the flicker threshold depends on the stimulus duration and on the number of cycles in the stimulus. The "De Lange" curves measured in this way can be described by a first-order high-pass filter in combination with a fourth-order low-pass filter.
Subject(s)
Photic Stimulation/methods , Visual Perception , Humans , Psychophysics , Sensory Thresholds , Time FactorsABSTRACT
The threshold gradient for perception of a linear change in luminance with time has been measured as a function of the stimulus duration. These data are compared with the "De Lange" curves representing the flicker sensitivity measured with intermittent presentation of the stimulus as a function of the stimulus duration. For this purpose it is necessary to take into account the fact that a linear luminance gradient, being a relatively low-frequency signal, is affected less by the low-pass filter supposedly situated in the visual system than by a sinusoidal signal (flicker) of the same duration.
