Abstract ··································································································· i List of contents ·························································································· ii
Ⅰ. Introduction 1.1 Auditory scene analysis ····································································· 1 1.2 Neural mechanisms for noise-invariant representations of acoustic signals mixed with background noise ······················································································· 2 1.3 Inferior colliculus ············································································· 4 1.3.1 Auditory processing pathway ························································· 4 1.3.2 Auditory processing hub: Inferior colliculus ········································ 6 1.4 Current research ·············································································· 7
Ⅱ. Research Methodology 2.1 in vivo electrophysiology ···································································· 9 2.2 Acoustic stimuli ·············································································· 9 2.3 Data analysis ················································································ 10
Ⅲ. Results 3.1 Acoustic stimuli: Mouse vocalization with different types of background noise ·· 11 3.2 Neuronal response patterns to vocalization signal and background noise in the inferior colliculus (IC) ························································································· 14 3.3 Water stream SNR shows better signal extraction at lowest SNR ··················· 19 3.4 Greater responsiveness of the more resistant neurons both to signal and noise ··· 24 3.5 Dynamic change of neuronal membership between Resistant and Susceptible groups across background noise types ······································································ 27 3.6 Lack of Significant Differences between Ascending and Descending conditions · 32
