Related Experiment Video
Updated: Apr 29, 2026

A Lightweight, Headphones-based System for Manipulating Auditory Feedback in Songbirds
Published on: November 26, 2012
Ambient noise causes independent changes in distinct spectro-temporal features of echolocation calls in horseshoe
Steffen R Hage1, Tinglei Jiang2, Sean W Berquist3
1Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA 90095-7246, USA Department of Animal Physiology, Institute of Neurobiology, Tübingen University, 72076 Tübingen, Germany steffen.hage@uni-tuebingen.de.
Abstract:
One of the most efficient mechanisms to optimize signal-to-noise ratios is the Lombard effect - an involuntary rise in call amplitude due to ambient noise. It is often accompanied by changes in the spectro-temporal composition of calls. We examined the effects of broadband-filtered noise on the spectro-temporal composition of horseshoe bat echolocation calls, which consist of a constant-frequency component and initial and terminal frequency-modulated components. We found that the frequency-modulated components became larger for almost all noise conditions, whereas the bandwidth of the constant-frequency component increased only when broadband-filtered noise was centered on or above the calls' dominant or fundamental frequency. This indicates that ambient noise independently modifies the associated acoustic parameters of the Lombard effect, such as spectro-temporal features, and could significantly affect the bat's ability to detect and locate targets. Our findings may be of significance in evaluating the impact of environmental noise on echolocation behavior in bats.
More Related Videos
07:13Modified Experimental Conditions for Noise-Induced Hearing Loss in Mice and Assessment of Hearing Function and Outer Hair Cell Damage
Published on: February 10, 2023
07:52Author Spotlight: Investigating Vocal Information Representation in Small Primates and Its Alteration by Psychiatric Disorders Using Noninvasive EEG
Published on: July 26, 2024
Related Concept Videos
Echo
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case,...
Convergent Evolution
The Cochlea
Hearing
Perception of Sound Waves
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same...
Doppler Effect - II