Une souris explore l’environnement d’un dispositif de test de mémoire spatiale
Mouse exploring its environment in an arena designed to test its spatial memory. The test is based on the capacity of mice to remember the location of objects present in the arena. The first stage involves placing the individual in the arena with two identical objects so it can familiarise itself with them and learn their position. A striped visual pattern helps the mouse orient itself in the space. To avoid placing the animal under stress, the test environment does not receive direct light. After this first exploratory phase, the mouse is returned to the same arena one hour or several days later to test its short- or long-term memory. For this second session, one of the two objects is moved, introducing spatial novelty. However, the other object is not moved, making it the reference object. A mouse whose memory is intact will show greater interest in the object that has been moved, and will tend to explore it for longer than the reference object. The movements and behaviour of the animal are monitored via camera and analysed using trajectory analysis software. In this way, the arena can be used to evaluate the mnesic capacities of different mouse lines and highlight memory problems, such as in Alzheimer's disease models, for example.