Anxiety-related behaviors in mice are often assessed over short periods starting immediately after introducing the animals in a dedicated apparatus. In these usual conditions (5−10 min periods), the cerebellar Lurcher mutants showed disinhibited behaviors characterized by abnormally high exploration of the aversive areas in the elevated plus-maze test. We nevertheless observed that this disinhibition sharply weakened after 10 min. We therefore decided to further investigate the influence of the disinhibition on the intrinsic and anxiety-related exploratory behaviors in Lurcher mice, with a special focus on familiarization effects. To this end, we used an innovative apparatus, the Dual Maze, permitting to tune the familiarization level of animals to the experimental context before they are faced with more (open configuration of the device) or less (closed configuration of the device) aversive areas. Chlordiazepoxide administration in BALB/c mice in a preliminary experiment confirmed both the face and the predictive validity of our device as anxiety test and its ability to measure exploratory motivation. The results obtained with the Lurcher mice in the open configuration revealed that 20 min of familiarization to the experimental context abolished the behavioral abnormalities they exhibited when not familiarized with it. In addition, their exploratory motivation, as measured in the closed configuration, was comparable to that of their non-mutant littermates, whatever the level of familiarization applied. Exemplifying the interest of this innovative device, the results we obtained in the Lurcher mutants permitted to differentiate between the roles played by the cerebellum in exploratory motivation and stress-related behaviors.

小鼠的焦虑相关行为通常在将动物引入专用仪器后立即开始的短时间内进行评估。在这些通常情况下（5-10 分钟），小脑 Lurcher 突变体表现出不受抑制的行为，其特征是在高架十字迷宫测试中对厌恶区域的异常高探索。尽管如此，我们观察到这种去抑制在 10 分钟后急剧减弱。因此，我们决定进一步研究去抑制对 Lurcher 小鼠内在和焦虑相关探索行为的影响，特别关注熟悉效应。为此，我们使用了一种创新装置，双迷宫，允许在动物面临更多（设备的开放配置）或更少（设备的封闭配置）厌恶区域之前，将动物的熟悉程度调整到实验环境。在初步实验中对 BALB/c 小鼠施用氯氮卓证实了我们的设备作为焦虑测试的面部和预测有效性及其测量探索动机的能力。Lurcher 小鼠在开放配置中获得的结果表明，熟悉实验环境 20 分钟消除了他们在不熟悉环境时表现出的行为异常。此外，在封闭配置中衡量的他们的探索动机与他们的非突变同窝仔的探索动机相当，无论应用的熟悉程度如何。