Neural coding and plasticity in the auditory system
Neural Coding and Plasticity in the Auditory System
We use a multidisciplinary approach encompassing anatomical, electrophysiological, imaging, behavioural and computational techniques to study the neural basis for auditory perception. We are investigating the cortical areas that are activated during auditory location, pitch or timbre discrimination tasks, the behavioural consequences of inactivating those areas or removing their projections, and the manner in which the tuning properties of their neurons evolve as behavioural performance improves in different perceptual learning tasks.
By carrying out a ‘neurometric’ analysis of the responses of the recorded neurons and comparing this with ‘psychometric’ data obtained from the behavioural measurements, we hope to be able to specify the physiological changes that are responsible for (and not just correlated with) behavioural performance. These experiments will contribute to our understanding of how biologically important information is represented, coded and stored within the cortex, and will shed light on the current controversy concerning the extent to which different attributes of sound are processed within different cortical areas.
We are also investigating the locus and nature of the physiological changes that take place during training-induced adaptation to altered auditory inputs and stimulus-timing-dependent plasticity. Having identified the neural networks that are reorganised in response to sensory experience and behavioural training, we hope to establish the rules that govern cortical plasticity and the cellular mechanisms responsible. In particular, we are examining the role of multisensory experience and of the neuromodulatory inputs from the basal forebrain in mediating auditory cortical plasticity, as well as continuing our in vitro studies of visual-auditory integration in the developing midbrain.
Our perceptual learning paradigms are also being used to investigate the mechanisms underlying the capacity of the brain to recover basic functions that have been compromised as a result of peripheral impairments. Our aim is therefore not only to improve our understanding of the plasticity of the brain, with its wider implications for the neurobiology of learning and memory, but also to use this information practically to stimulate new developments that will help to alleviate deficits in central auditory processing.