Response uncertainty and perceptual difficulty of auditory temporal patterns

Two qualitatively different sounds were used to generate256 different sequences of length8, and these sequences were presented to Ss at a rate of two stimuli per second. These sequences, when repeatedcontinuously,canbe grouped into20 fundame ntally different patterns, each having either2, 4, or8 distinguishably different starting points. Ss were required to listen and to be gin responding (with telegraph keys) in synchrony to the patterns when they were able. The point at which they began responding, the delay before responding, and errors after beginning responding were measured. The response uncertainty (variability of point of response for a given pattern), average delay, and average errors are all highly correlated, indicating that patterns which are easily organized are those which have few alternative modes of organization, and thus can be considered as simple, or good in the Gestalt sense.