The what, where and how of auditory-object perception

Jennifer K. Bizley, Yale E. Cohen
2013 Nature Reviews Neuroscience  
The fundamental perceptual unit in hearing is the 'auditory object'. Similar to visual objects, auditory objects are the computational result of the auditory system's capacity to detect, extract, segregate and group spectrotemporal regularities in the acoustic environment; the multitude of acoustic stimuli around us together form the auditory scene. However, unlike the visual scene, resolving the component objects within the auditory scene crucially depends on their temporal structure. Neural
more » ... rrelates of auditory objects are found throughout the auditory system. However, neural responses do not become correlated with a listener's perceptual reports until the level of the cortex. The roles of different neural structures and the contribution of different cognitive states to the perception of auditory objects are not yet fully understood. Hearing and communication present various challenges for the nervous system. To be heard and to be understood, an auditory signal must first be transformed from a time-varying acoustic waveform into a perceptual representation (FIG. 1) . This is then converted to an abstract representation that combines the extracted information with information from memory stores and semantic information 1 . Last, this abstract representation must be interpreted to guide the categorical decisions that determine behaviour. Did I hear the stimulus? From where and whom did it come? What does it tell me? How can I use this information to plan an action? There is broad agreement that the ventral auditory pathway -a pathway of brain regions that includes the core auditory cortex, the anterolateral belt region of the auditory cortex and the ventrolateral prefrontal cortex -has a role in auditory-object processing and perception 2-5 . However, no consensus has been reached on either the roles of different regions in this pathway in specific elements of auditory-object processing and perception or the contributions of particular cognitive states (such as attention) to the differential modulation of activity along this pathway. Here, we discuss how the brain transforms an acoustic-based representation of a stimulus into one that is object-based. We consider how object-related neural activity might emerge and how attention and behavioural state influence perception and neural activity. We also review what is known and, more
doi:10.1038/nrn3565 pmid:24052177 pmcid:PMC4082027 fatcat:armchexndvbkhd26xrmbonkpty