Influence of a chronic ultramild stress procedure on decision-making in mice.

Abstract

OBJECTIVE: To test the influence of a chronic ultra mild stress (CUMS) procedure, based solely on socio-environmental stressors, on cognitive-behavioural function in mice. DESIGN: Behavioural study. PARTICIPANTS: B6D2F1 mice. INTERVENTIONS: Mice were exposed to various stressors and then tested using a decision-making task. RESULTS: We observed that stress facilitated "choice" behaviour, with an absence of "no choice" behaviour. Stress also facilitated a more rapid capacity to process information, a decrease in the level of evaluation of the choice situation and less hesitation. These stress-related consequences on decision making may be attributed to a higher level of distractability in the stressed mice. CONCLUSIONS: The CUMS model may be useful for the study of stress-related disorders by proposing a new method for assessing gene-environment interactions in cognitive-affective behaviours.