Behavioral flexibility is an essential skill for daily living and often survival. Different study groups have reported that mice with genetic ablation or pharmacological inhibition of mGluR5 showed impairments in fear memory extinction and spatial reversal learning, indicating that mGluR5 signaling is involved in the regulation of behavioral flexibility. While most of these behavioral studies exposed the testing mice in high stress conditions using electric foot-shocks and forced water swimming, mGluR5 has also been reported to be implicated in the stress response. Therefore, evaluating the direct role of mGluR5 in low stress condition is important, to clearly distinguish between stress-induced cognitive rigidity and the mGluR5 gene effect. So in our study, we have evaluated behaviors of WT and mGluR5 KO mice in a low stress rodent touchscreen operant platform using the appetitive conditioning. Groups of adult male mice were evaluated in a series of touchscreen tasks including two-choice visual discrimination-reversal, extinction, ratio-schedules and the effort-related choice. As a result, mGluR5 KO mice showed impairments in reversal and extinction, which was driven by a perseverative responding behavior. Altogether, our results indicate that mGluR5 signaling has a critical role in behavioral flexibility.

To: 要旨(抄録)