The olfactory hole-board test in rats: a new paradigm to study aversion and preferences to odors

Abstract

Odors of biological relevance (e.g., predator odors, sex odors) are known to effectively influence basic survival needs of rodents such as anti-predatory defensiveness and mating behaviors. Research focused on the effects of these odors on rats’ behavior mostly includes multi-trial paradigms where animals experience single odor exposures in subsequent, separated experimental sessions. In the present study, we introduce a modification of the olfactory hole-board test that allows studying the effects of different odors on rats’ behavior within single trials. First, we demonstrated that the corner holes of the hole-board were preferentially visited by rats. The placement of different odors under the corner holes changed this hole preference. We showed that holes with carnivore urine samples were avoided, while corner holes with female rat urine samples were preferred. Furthermore, corner holes with urine samples from a carnivore, herbivore, and omnivore were differentially visited indicating that rats can discriminate these odors. To test whether anxiolytic treatment specifically modulates the avoidance of carnivore urine holes, we treated rats with buspirone. Buspirone treatment completely abolished the avoidance of carnivore urine holes. Taken together, our findings indicate that the olfactory hole-board test is a valuable tool for measuring avoidance and preference responses to biologically relevant odors.

Predator odour but not TMT induces 22-kHz ultrasonic vocalizations in rats that lead to defensive behaviours in conspecifics upon replay

“…Additionally, TMT induced a significant increase in immobility, one of the most prominent behavioural effects of TMT 24 , 40 . Surprisingly, exposure to fox urine did not induce overt defensive behaviour in the present experiment, although this has been shown in previous studies of our group 20 , 41 – 44 and of others 45 – 47 . A potential reason for this may be that the experimental protocol of the present study differed from the one used before.…”

Cognitive training improves the disturbed behavioral architecture of schizophrenia-like rats, “Wisket”

“…Increased stress reactivity has repeatedly been reported in patients suffering from psychiatric diseases [35,37], and it is suggested that cognitive deficits in schizophrenia may also arise, at least partially, from the increased stress sensitivity and the consequently decreased motivation/attention [31,35,38]. In accordance with the observation that animals with a higher degree of anxiety prefer the peripheral region in open field [4,39], our data revealed that the external side boxes were recognized and preferred by Wisket rats. This points to a higher Table 3 Definitions, abbreviations, means and significances of the different parameters detected in the AMBITUS system, and shown in Fig.…”

Characterization of exploratory activity and learning ability of healthy and “schizophrenia-like” rats in a square corridor system (AMBITUS)

“…This phenomenon seems to be similar to a preference of the peripheral holes compared to the central ones in the hole-board test Wernecke & Fendt, 2015). Since the experiments were performed in dim light without external cues, the learning in the corridor could essentially be considered a form of an egocentric task solved by learning the association between its egocentric body response and the reward (Vorhees & Williams, 2014;Buzsaki & Moser, 2013).…”