Hippocampal communication with the anterior olfactory nucleus is necessary for context-dependent odor memory.

The hippocampus plays a critical role in contextual learning and memory processes. The ability to associate memories and behaviors with the learning context likely involves interactions between the hippocampus and other brain regions where the basic elements of the memory may be encoded. Here, we examined interactions of the hippocampus and the olfactory system using a contextually cued conditional discrimination task that required rats to remember that one odor from a pair of odor cues is rewarded in one context, but the opposite odor is rewarded in a different context. We used muscimol to inactivate the anterior olfactory nucleus, a key target for hippocampal output to the olfactory system, and the ventral hippocampus. We also performed crossed-hemisphere inactivation of the anterior olfactory nucleus in one hemisphere and the hippocampus in the other. All three inactivation procedures severely impaired performance. These results indicate that interactions between the hippocampus and anterior olfactory nucleus are critical for context-dependent odor memory. (PsycInfo Database Record (c) 2026 APA, all rights reserved).