Abstract
When perceiving multi-stable visual illusions such as the silhouette dancer illusion (Kayahara, 2003) or the Ames Window (Ames, 1951), it is easy to become trapped in a specific percept for a while before switching. The same phenomenon can occur in auditory illusions - in VSS 2013 (Bainbridge et al) we discovered a quadri-stable auditory illusion, the Transverse and Bounce Illusion. Based on front-back confusion, the sound can be perceived as having four trajectories of approaching and withdrawing from the listener. Listeners can perceive the same sound as traveling transversely through them from front-to-back or back-to-front, or they can perceive it as bouncing exclusively in front or in back. In our initial study, we found no perceptual bias when the illusion played non-continuously. Here, we recreate the illusion continuously in headphones to test its perceptual stability and the probability of switching from one state to the others. Sixteen listeners responded whether the sound was in front, in back, or at them (middle). The illusion was delivered for twenty-one blocks of one minute each, followed by a ten second break to release any perceptual locking. An untimed break was offered every seven blocks. We found listeners to be significantly biased towards perceiving the sounds travelling through them (the transverse condition), as opposed to bouncing off of them (p<0.0001). There was no significant difference between trials of different directions within these two conditions. During transverse percepts, listeners became significantly locked in a percept of switching back and forth between the front-to-back and back-to-front percepts (p<0.0001). Follow-up multi-modal studies explore how transient visual events can manipulate auditory reversal probabilities and the frequency at which people switch between auditory percepts.
Meeting abstract presented at VSS 2014