Behavioural mechanisms underlying rapid responses of rodents in an operant conditioning paradigm

Abstract

In a natural setting, sensory awareness aids the animal in evaluating its surroundings and making appropriate judgments. The results of these choices have an impact on the animal's habitat survival and fitness. Rodents primarily rely on their olfactory system to get information and carry out necessary tasks for their survival, including finding possible mates, foraging, navigating, seeing predators, etc. Based on a well- known Go/No-Go olfactory behavioural paradigm, we train mice in our lab to execute detection and discriminating tasks. Water-deprived animals learn to lick for rewarded stimuli (reward being water) and to refrain from licking for non-rewarded input. Animals gradually develop the ability to distinguish between odour stimuli that are rewarded and those that are not. However, a preliminary study from the lab shows that animals that execute as accurately as possible respond to certain unrewarding stimuli by licking and quickly stop responding. These quick licking reactions may be the result of inadequate stimulus percept generation, in which a preliminary judgement was made prior to thorough processing and integration of the incoming stimulus. In order to characterize this behavior, we carried out Go/No-Go odor discrimination tasks and established a means to record these anomalies as reversal trials with its own set of characteristics. Further experiments were carried out to look at the significance of an odor vs a diluent in an odor discrimination task. This project aimed at attempting to quantify and characterize the properties of reversal trials and this phenomenon overall. Our findings call for further experiments to dissect out the physiological mechanism and behavioural impact of the same which will help us establishing this property as a usable readout to quantify finer subtleties in the decision making process.