Predator odor avoidance as a rodent model of anxiety Learning-mediated consequences beyond the initial exposure

Prey animals such as rats display Innate defensive responses when exposed to the odor of a predator providing a valuable means of studying the neurobiology of anxiety While the unconditioned behavioral and neural responses to a single predator odor exposure have been well documented the paradigm can also be used to study learning-dependent adaptations that occur following repeated exposure to a stressor or associated stimuli In developing preclinical models for human anxiety disorders this is advantageous as anxiety disorders seldom involve a single acute experience of anxiety but rather are chronic and/or recurring illnesses Part 1 of this review summarizes current research on the three most commonly used predator-related odors cat odor ferret odor and trimethylthiazoline (a component of fox odor) Part 2 reviews the learning-based behavioral and neural adaptations that underlie predator odor-induced con text conditioning one trial tolerance sensitization habituation and dishabituation (C) 2010 Elsevier Inc All rights reserved