The Roles of Central Amygdala D1 and D2 Receptors on Attentional Performance in a Five-Choice Task

The central amygdala (CeA) has been shown to play an important role in mediating several attentional processes, including selective and sustained attention. Emerging evidence suggests that the connections between the CeA and the midbrain dopamine areas are important for attentional processing. However, little is known about the role of dopaminergic input into the CeA in mediating attentional processes. To investigate how dopamine activity in the CeA modulates attentional processing, CeA D1 and D2 receptors were temporarily inactivated during testing in a 5-choice task. In this task, rats were trained to detect 1 of 5 recessed ports that briefly illuminated in order to receive a food reward, therefore requiring the rats to successfully sustain their attention to monitor all 5 ports and selectively attend to the lit port. Then, rats were tested in several altered versions of the task to increase attentional load (e.g., variable ready period). In 2 experiments, the D1 antagonist CH 23390 or the D2 antagonist raclopride were infused into the bilateral CeA preceding the test sessions. D1, but not D2, inactivation reduced performance in the more demanding versions of the 5-choice task. Therefore, CeA D1 receptors might mediate attentional functions important for visual cue detection in a 5-choice task.