Listening involves making sense of the numerous competing sound sources that exist around us. The neuro-computational challenge faced by the brain is to pull apart the sound mixture that arrives at the ear and reconstruct the original sound sources; this process is known as auditory scene analysis. While young normal hearing listeners can parse an auditory scene with ease, the neural mechanisms that allow the brain to do this are unknown – and we are not yet able to recreate them with digital technology. Hearing loss, aging, impairments in central auditory processing, or an inability to appropriately engage attentional mechanisms can negatively impact the ability to listen in complex and noisy situations and an understanding of how the healthy brain organizes a sound mixture. into perceptual sources may guide rehabilitative strategies targeting these problems.
While functional imaging studies in humans highlight a network of brain regions that support auditory scene analysis, little is known about the cellular and circuit based mechanisms that operate within these brain networks. A critical barrier to advancing our understanding of how the brain solves the challenge of scene analysis has been a failure to combine behavioural testing, which provides a crucial measure of how any given sound mixture is perceived, with methods to record and manipulate neuronal activity in animal models. In SOUNDSCENE we combine complex behavioural tasks, that mimic those that human listeners face in everyday situations, with methods to observe and manipulate neural activity. Our goal is to understand how a network of brain regions: auditory cortex, prefrontal cortex and hippocampus enable scene analysis during active listening. We will understand how processing within each area, and the interactions between these areas, underpins auditory scene analysis. This knowledge will increase our knowledge of fundamental brain function, and may contribute to biologically inspired machine listening devices, and improvements in hearing aid and cochlear implant signal processing methods.