The Development of Auditory ICONS for Representation of Virtual Objects in 3-D Space

The ability of subjects to localize and identify each member of a set of acoustic signals will be measured. The acoustic signals will be presented in random order at several locations in auditory space, also chosen randomly. The acoustic signals are constructed to maximize the cues they present for localization and identification in that they contain a wide range of frequencies and timing information. The signals will be convolved with Head-Related Transfer Functions to produce sounds that are localized externally, i.e., in 3-D auditory space, even though presented via earphones. Subjects will indicate their localization of the sounds by orienting their head toward the perceived source and the azimuth and elevation of the head will be read from a magnetic head -tracker worn by the subject. In addition the subjects will indicate their confidence in the judgement of localization and will identify the signal. Thus, the security, or certainty, of the judgements about the localization of auditory objects, or icons, will also be estimated.