Object and Setting Identification in Natural Auditory Scenes

We encounter situations each day that require our auditory system to quickly interpret our surroundings. Auditory scene perception involves complex processes that allow us to identify both the setting and the objects within a scene, which are essential for decision-making, and situational awareness. While there is substantial evidence for distinct cortical regions and pathways supporting visual scene and object recognition, far less is known about how the brain processes complex auditory scenes and objects. This study aimed to determine whether distinct mechanisms underlie auditory setting and object identification and whether these mechanisms interact to aid perception. Participants listened to 200 natural auditory scenes of varying durations (1, 2, and 4 sec) and identified the setting (e.g., café) as well as the objects (e.g., talking, espresso machine, music) within each scene. Overall, performance was highest on the object identification task, and there was a significant interaction between task and scene duration, with a greater benefit of longer durations for the object identification task. Different low- and mid-level acoustic features of the scenes predicted performance on the two tasks. These results suggest that the auditory system employs distinct (and potentially interactive) computations for setting and object identification, allowing for quick interpretation of complex, real-world auditory scenes. The interaction between task performance and scene duration further suggests object and setting identification may operate on different temporal scales; objects might require more time for accurate individuation, while settings may be recognized more efficiently through global properties of scenes, such as openness or naturalness.