Enhanced signal detectability in comodulated noise introduced by compression
Related Experiment Video
Updated: Jun 30, 2026

Studying Cavitation Enhanced Therapy
Published on: April 9, 2021
Michael Buschermöhle1, Ulrike Feudel, Jan A Freund
1International Graduate School for Neurosensory Sciences, Carl-von-Ossietzky Universität Oldenburg, 26111, Oldenburg, Germany. buschermoehle@icbm.de
Abstract:
Many examples of natural noise show common amplitude modulations at different frequency regions. This kind of noise has been termed comodulated noise and is widely examined in hearing research, where an enhanced detectability of pure tones and narrow noise bands in comodulated noise compared to unmodulated noise is well known as the CMR or CDD effects, respectively. Here it is shown that only one signal processing step, a compressive nonlinearity motivated by the peripheral auditory system, is sufficient to explain a considerable contribution to these effects. Using an analytical approach, the influence of compression on the detectability of periodic and narrow band signals in the presence of unmodulated and comodulated noise is investigated. This theoretical treatment allows for identifying the mechanism leading to improved signal detection. The compressive nonlinearity constitutes an adaptive gain which selectively boosts a stimulus during time spans of inherently increased signal-to-noise ratio and attenuates it during time spans dominated by noise. On average, these time spans are more pronounced in stimuli with comodulated noise than with unmodulated noise, thus giving rise to the observed CMR and CDD effects.
Related Concept Videos
Difference from Background: Limit of Detection
The LOD indicates the presence or absence...
Upsampling
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
Reconstruction of Signal using Interpolation
Aliasing
If the sampling frequency is below the Nyquist rate, these replicas overlap, preventing the original signal...
Downsampling
The Fourier transform of the decimated sequence reveals a combination of scaled and shifted versions of the original spectrum. This...