Dopamine D2 receptors mediate two-odor discrimination and reversal learning in C57BL/6 mice

摘要: Dopamine modulation of neuronal signaling in the frontal cortex, midbrain, and striatum is essential for processing integrating diverse external sensory stimuli attaching salience to environmental cues that signal causal relationships, thereby guiding goal-directed, adaptable behaviors. At cellular level, dopamine mediated through D1-like or D2-like receptors. Although a role receptors variety goal-directed behaviors has been identified, an explicit involvement D2 not clearly established. To determine whether receptor-mediated contributes associative reversal learning, we compared C57Bl/6J mice completely lack functional wild-type with respect their ability attach appropriate (stimulus discrimination) disengage from inappropriate behavioral strategies when reinforcement contingencies change (e.g. learning). Mildly food-deprived female receptor deficient rapidly learned retrieve consume visible food reinforcers small plastic dish. Furthermore, both genotypes readily dig same dish filled sterile sand order locate buried pellet. However, required significantly more trials than discriminate between two dishes, each different scented sand, associate one odors presence reinforcer (food). In addition, repeatedly fail alter response patterns during where rules were inverted. Inbred develop complete absence are capable olfaction but display impaired acquire odor-driven contingencies. adjust responding previously reinforced stimulus unexpected outcomes encountered impaired. These findings suggest by important regulating learning may have implications treatment human attention disorders.