Abstract:

In separate experiments, detection and identification thresholds were obtained for a set of 25 common environmental sounds (e.g., dog barking, car starting). In the detection task, threshold values of the event-to-noise ratio (Ev/N) were established using an adaptive tracking procedure. The identification experiment was part of a larger individual differences study reported earlier [Watson et al., J. Acoust. Soc. Am. 99, 2516(A) (1996)]. A 3AFC identification task was used, with sounds presented at eight levels of Ev/N. Thresholds were estimated from the psychometric functions derived from the data. The correlation between thresholds in the two tasks indicates that the identifiability of these sounds is only weakly related to their detectability. Several models were evaluated to identify the properties that determine the detectability of environmental sounds. Leaky integrator and cross-correlation models were used to predict detection data; identification data were evaluated using a multidimensional scaling algorithm.