Effect of smooth vs step interval gradients upon interval gap detection

The effect of smooth and step-wise auditory interval gradients upon the discrimination of an interval change, or gap, was studied. Gap discrimination was substantially better with smooth interval gradients than with step gradients when the gap was surrounded by a large number of intervals. This result leads us to ask whether gradiënt phenomena of the Mach-band type are critically dependen t upon the existence of smooth, rather than step, gradients