Enhanced multi-channel model for auditory spectrotemporal integration

Abstract

In psychoacoustics, a multi-channel model has traditionally been used to describe detection improvement for multicomponent signals. This model commonly postulates that energy or information within either the frequency or time domain is transformed into a probabilistic decision variable across the auditory channels, and that their weighted linear summation determines optimum detection performance when compared to a critical value such as a decision criterion. In this study, representative integration-based channel models, specifically focused on signal-processing properties of the auditory periphery are reviewed (e.g., Durlach's channel model). In addition, major limitations of the previous channel models are described when applied to spectral, temporal, and spectrotemporal integration performance by human listeners. Here, integration refers to detection threshold improvements as the number of brief tone bursts in a signal is increased. Previous versions of the multi-channel model underestimate listener performance in these experiments. Further, they are unable to apply a single processing unit to signals which vary simultaneously in time and frequency. Improvements to the previous channel models are proposed by considering more realistic conditions such as correlated signal responses in the auditory channels, nonlinear properties in system performance, and a peripheral processing unit operating in both time and frequency domains.

Low-Intensity Steady Background Noise Enhances Pitch Fusion Across the Ears in Normal-Hearing Listeners

“…Stochastic resonance is a phenomenon where a signal transmission in a nonlinear system is enhanced by the addition of an external noise. This effect has been observed in many human sensory functions including visual perception (Kitajo et al, 2003;Sasaki et al, 2006;Aihara et al, 2008), somatosensation (Collins et al, 1996), and auditory perception (Zeng et al, 2000;Chatterjee and Robert, 2001;Allingham et al, 2003;Paglialonga et al, 2010;Tanaka et al, 2010;Martignoli et al, 2013;Oh et al, 2015;Othman et al, 2019). All of these studies have revealed that the addition of a small but optimal level of external noise to each sensory system enhances its response (detection or discrimination) to an input signal, whereas adding large amount causes it to deteriorate (masking).…”

“…In the area of auditory perception, findings in healthy auditory system showed that the addition of noise improved auditory phase response (Tanaka et al, 2010), auditory detection performance for complex signals (Oh et al, 2015), and auditory working memory (Othman et al, 2019). Other studies tested damaged auditory systems and also showed that an optimal amount of the noise enhanced auditory modulation sensitivity (Chatterjee and Robert, 2001) and frequency discrimination ability (Zeng et al, 2000) in cochlear implant (CI) users, specifically.…”