The Features Of AAM Under Mono-sound And Multi-sound Source Conditions

Auditory apparent motion(AAM), is a sound movement illusion heard when static sounds presented in sequence under appropriate temporal and spatial conditions, also, it is the most common method to study the psychological mechanism of dynamic audition. The study tested factors affect AAM under mono-sound source and multi-sound source, tries to probe into the general characteristics of AAM and to provide some ergonomical guidelines in interface design related to human audition.Two experiments were conducted in this free-field study. In the first experiment, AAM was measured when sound sources were located in the vertical median plane under binaural and monaural listening conditions, while the number of sound sources, ISI and burst duration were manipulated. In the second experiment, AAM was examined when sound sources were located in the right horizontal plane under monaural condition, while the separation between sound sources, ISI and burst duration were manipulated. In both of the two experiments, subjects were instructed to report their motion and direction perception to each stimuli sequence.The results indicated that:1. AAM motion perception was determined by number of sound sources when mono-sound source were presented; Separation affected AAM direction perception significantly in the right horizontal median plane;2. Listening conditions did not fluctuate AAM performance in the vertical median plane significantly: Binaural conditions did not taken the precedence over monaural aspect both in AAM motion and direction perception ; 3. A minimum integration time(MIT) seemed to be indispensable to the AAM perception of auditory system.