The Effects of Visual Cues and Interstimulus Interval on Accuracy in Auditory Localization and Detection. zyxw Joseph T. Coyne Old Dominion University Norfolk, Virginia Mark D. Lee Pitney Bowes Shelton, Connecticut Auditory localization is an increasingly important topic zyxw as the technology for audio displays is becoming more available. However, few studies examine the effects of multiple simultaneous distracters on auditory detection and localization performance. Previous research has found that detection and localization performance significantly drop as the number of distracters increases; however, it is not clear what causes these errors. In the present study, participants either had to localize an auditory stimulus or detect an auditory stimulus among multiple distracters. Similar to previous research the number of errors significantly increased as the number of active speakers increased. Also consistent with previous research, the detection performance was better than the localization performance. The use of visual cues was found to benefit the localization group but did not significantly affect performance in the detection group. The present study also found that a longer interstimulus interval improved accuracy only in the localization group, and then only when visual cues were present. These findings provide insight into the complex nature of the auditory search task. INTRODUCTION The present study investigates how visual cues and interstimulus interval (ISI) affect accuracy in auditory search. Research indicates that the amount of background noise (Good zyxwvuts & Gilkey, 1996) or the number of sound sources (Lee 2001, Coyne & Lee, 2000) significantly affects our ability to localize and attend to preferred sounds. studies using dichotic listening tasks, where different auditory stimuli were simultaneously presented to each ear. Moray (1959) found that participants could easily recall their own name when presented to an unattended auditory channel. This phenomenon is known as the "Cocktail Party Effect" because it resembles our ability to hear our own name in a conversation to which we are not attending. Dichotic listening tasks demonstrate the ability to attend to auditory stimuli in the presence of at least one simultaneous auditory distracter. Few studies have investigated performance in more complex auditory environments. Tasks such as driving require individual to monitor multiple Auditory attention literature is based largely on auditory stimuli. What happens to auditory attention when there are more than two simultaneous stimuli? Lee (2001) investigated performance on an auditory search task, where observers had to monitor between 2 to 6 simultaneous sounds for the presentation of a target. Observers were required to identify which of six speakers presented the target. Performance significantly dropped with each increase in the number of active speakers. This effect is similar to those found in other domains such as visual search (Atkinson , Holmgren & Juola, 1969) and is referred to as the set size effect. Coyne and Lee (2000) conducted a follow up study to compare auditory detection with auditory localization. The set size effect was demonstrated in both tasks however was more pronounced in the localization task. effects of visual information on auditory search be examined. The addition of visual information represents a potential mechanism for improving auditory search performance. Additional visual information would serve as a cue or decision aid. Coyne and Lee (2000) recommended that the Proceedings of the Human Factors and Ergonomics Society 46th Annual Meeting -- 2002 PROCEEDINGS of the HUMAN FACTORS AND ERGONOMICS SOCIETY 46th ANNUAL MEETING -- 2002 1613 at HFES-Human Factors and Ergonomics Society on September 11, 2015 pro.sagepub.com Downloaded from