Detecting the temporal asynchrony among components of multicomponent complexes

Abstract

The listener's task was to detect onset or offset asynchrony among sets of equal‐amplitude sinusoids. In the standard condition, all components were started (or stopped) at the same time. In the asynchrony condition, their onset (or offset) times were chosen from a Gaussian distribution with a certain standard deviation. The value of this standard deviation was adjusted in an adaptive 2AFC procedure to determine the asynchrony threshold. Parameters investigated, in addition to the differences between onset and offset asynchrony, were rise (fall) time of the components, frequency spacing (linear and logarithmic) of the components, and the number of components. The obtained asynchrony thresholds measured in 2AFC tasks ranged from 0.1 to 3 ms for 20‐component complexes. In these experiments, the temporal events to be compared occurred in different frequency channels. A control experiment was conducted which indicated that the obtained results could not be explained on the basis of the perception of the wideband waveform.