Perceiving the initial note: quantitative models of how listeners parse cyclical auditory patterns.

In this paper, we explore the rules followed by the auditory system in grouping temporal patterns. Imagine the following cyclical pattern (which we call an "auditory necklace"-AN for short-because those patterns are best visualized as beads arranged on a circle) consisting of notes (1s) and rests (0s): … 1110011011100110 …. It is perceived either as repeating 11100110 or as repeating 11011100. We devised a method to explore the temporal segmentation of ANs. In two experiments, while an AN was played, a circular array of icons appeared on the screen. At the time of each event (i.e., note or rest), one icon was highlighted; the highlight moved cyclically around the circular array. The participants were asked to click on the icon that corresponded to the note they perceived as the starting point, or clasp, of the AN. The best account of the segmentation of our ANs is based on Garner's (1974) run and gap principles. An important feature of our probabilistic model is the way in which it combines the effects of run length and gap length: additively. This result is an auditory analogue of Kubovy and van den Berg's (2008) discovery of the additivity of the effects of two visual grouping principles (proximity and similarity) conjointly applied to the same stimulus.