Effect of interaural level and phase cues on intervening interference in auditory working memory for loudness

The focus of this study was to gauge the influence of intervening interference on an intensity standard held within auditory working memory through measurement of the just noticeable difference (JND) for intensity. Additionally, the use of interaural phase differences and interaural level differences as spatial cues were employed to identify whether these indicators provided a means for release from interference. A series of tones, both with and without spatial cues, were presented to subjects and responses were obtained using the method of constant stimuli. The JND for intensity was measured in a control condition with a silent inter-comparison interval and three conditions containing intervening tones within the temporal gap between the standard and comparison stimuli. The presence of intervening interference produced a significant increase in the intensity difference needed for discrimination. Further, the provision of spatial cues did not result in a significant release from this interference. These results indicate that a release from interference is not obtained when listeners are required to rely entirely on information used for spatial location (i.e., overall intensity differences and interaural phase/intensity differences) without unique information identifying the sound source to aid in retention of relevant information within auditory working memory.