A Neuronal Network Model for Context-Dependent Perceptual Decision on Ambiguous Sound Comparison

Summary

Date: 
February 19, 2015 - 2:30pm
Location: 
NW 243
About the Speaker
Name: 
Chengcheng Huang (Rinzel Group, NYU)

Many natural stimuli contain perceptual ambiguities that can be cognitively resolved by the surrounding context, e.g. preceding stimuli. In audition, preceding context can bias the perception of speech and non-speech stimuli. Here, we developed neuronal network model to account for how preceding auditory stimuli affects our perception of pitch change direction. Our model draws inspiration from a recent psychophysical experiment where listeners experienced opposite percepts (either ascending or descending) of an ambiguous tone pair depending on the spectral positions of the preceding tones. Our recurrent firing-rate network model can detect frequency change of successively played stimuli due to asymmetric inhibition. We propose a novel adaptation mechanism, facilitation of inhibitory synapses, which successfully accounts for the context-dependent perception demonstrated in behavioral experiments.