# what is an auditory object **Abstract:** | Objects are the building blocks of experience, but what do we mean by an object? Increasingly, neuroscientists refer to ‘auditory objects’, yet it is not clear what properties these should possess, how they might be represented in the brain, or how they might relate to the more familiar objects of vision. The concept of an auditory object challenges our understanding of object perception. Here, we offer a critical perspective on the concept and its basis in the brain. What is an object? The concept is not straightforward and has taxed philosophers and neuroscientists alike. Kant called the physical object ‘the thing in itself’, something that is unknowable1, whereas Berkeley maintained that all objects are mental events2. Objects cannot be known independently of sensory experience; in neuroscientific terms, the brain’s representation of an object must be based on information conveyed by one or more senses. Although vision has been the primary focus of neuroscientists, philosophers1,2 would contend that no single sense is intrinsically more valid than any other as a source of object information. The concept of an ‘auditory object’has recently attracted much attention among neuroscientists3–21, and raises fundamental questions about the nature of object perception in all sensory systems. The concept is attractive in that it indicates a sensory entity that might be processed in a similar way by different senses, using common modes of neural processing. Despite the growing enth