Human recognition of environmental sounds is not always robust to reverberation

Reverberation is ubiquitous in natural environments, but its effect on the recognition of non-speech sounds is poorly documented. To evaluate human robustness to reverberation, we measured its effect on the recognizability of everyday sounds. Listeners identified a diverse set of recorded environmental sounds (footsteps, animal vocalizations, vehicles moving, hammering, etc.) in an open set recognition task. For each participant, half of the sounds (randomly assigned) were presented in reverberation. We found the effect of reverberation to depend on the typical listening conditions for a sound. Sounds that are typically loud and heard in indoor environments, and which thus should often be accompanied by reverberation, were recognized robustly, with only a small impairment for reverberant conditions. In contrast, sounds that are either typically quiet or typically heard outdoors, for which reverberation should be less pronounced, produced a large recognition decrement in reverberation. These results demonstrate that humans can be remarkably robust to the distortion induced by reverberation, but that this robustness disappears when the reverberation is not consistent with the expected source properties. The results are consistent with the idea that listeners perceptually separate sound sources from reverberation, constrained by the likelihood of source-environment pairings.