Listening in a noisy world: the role of visual activity in auditory cortex for sound perception.

Our understanding of how neural activity patterns underlie perception is limited. Most studies examining auditory cortex have focussed on the relationship between an acoustic stimulus and the neural response. However, attention, behavioural context, and even visual stimulation, influence auditory cortical firing and any attempt at understanding the function of auditory cortex must integrate the influence of these non-acoustic factors. My research program aims to better understand how auditory co rtex functions for perception by considering these non-auditory factors. Specifically, I plan a series of experiments to elucidate the role that visual activity in auditory cortex plays in listening. Firstly, I will identify the origin of visual activity by selectively inactivating candidate visual and parietal cortical fields while recording in auditory cortex. Secondly, I will train animals in temporal and spatial auditory, visual and auditory-visual tasks and record from auditory cortex whils t they perform them. These data will allow us to correlate the single-trial behavioural and neural activity resulting from providing a multisensory cue. In order to test whether the correlations we observe actually underpin the animals perception, the third part of this proposal examines the implications of perturbing neural activity using micro- stimulation, during the discrimination of multisensory signals.