Citation

Pereira AG, Cruz A, Lima SQ, Moita MA. Curr. Biol. 2012; 22(16): R627-8.

Affiliation

Behavioral Neuroscience Lab, Champalimaud Neuroscience Programme at Instituto Gulbenkian de Ciência, Oeiras, Portugal.

Copyright

(Copyright © 2012, Elsevier Publishing)

DOI

10.1016/j.cub.2012.06.015

PMID

22917506

Abstract

Most of what we know about the neural basis of fear has been unravelled by studies using associative fear learning [1]. However, many animal species are able to use social cues to recognize threats [2,3], a defence mechanism that may be less costly than learning from self-experience. Most studies in the field have focused on species-specific signals, such as alarm calls or pheromones, remaining unclear whether more generic cues can mediate this process. Here we report that rats perceive the cessation of movement-evoked sound as a signal of danger and its resumption as a signal of safety. To study transmission of fear between rats we assessed the behavior of an observer while witnessing a demonstrator cage-mate display fear responses. Having tested a multitude of cues, we found that observer rats respond to an auditory cue which signals the sudden immobility of the demonstrator rat - the cessation of the sound of motion. As freezing is a pervasive fear response in animals [4,5], silence may constitute a truly public cue used by a variety of animals in the ecosystem to detect impeding danger.

Language: en