TIME ESTIMATION OF COMPOSITE STIMULI
It has been reported that the durations of moving objects, such as a set of moving dots circulating around a spot on a computer display, when shown for various intervals, appeared to last longer than its non-moving counterpart. In this study, the objects were of a different kind, i.e. in one condition, they were sinusoidally modulated luminance gratings moving downward, and in another, the amplitude of the same moving gratings were temporally modulated sinusoidally at a given frequency. As a control, durations of a stationary and fixed-luminance patch, which was of the same size as the other targets, were also judged. Five women and two men took part as observers. Instead of the usual magnitude estimation, the method of converging limits was used for the estimation of the durations of the targets. The results indicated that the more complex were the targets, the longer were they judged in duration. The exponents for the function relating the real to the estimated durations, were somewhat higher for the steady luminance stimuli.