Parallel activity in orbitofrontal cortex and hippocampus shapes cognitive maps and schemas, study suggests

As humans and other animals navigate their surroundings and experience different things, their brain creates so-called cognitive maps, which are internal representations of environments or tasks. These mental maps are eventually generalized into schemas, frameworks that organize information acquired through experience and can later guide decision-making.

Various past neuroscience and psychology studies have tried to better understand the neural processes and brain regions that support the formation of these internal representations. Insight into these mechanisms could, in turn, shed light on the underpinnings of learning and decision-making.

Two brain regions that have been found to play a role in forming internal representations of experiences are the orbitofrontal cortex (OFC) and the hippocampus (HC). Among other functions, the OFC supports reward-based learning and decision-making. At the same time, the HC contributes to spatial navigation and the formation and retrieval of memories.

Researchers at the National Institute of Drug Abuse in Baltimore recently carried out a study to further investigate how these two brain regions support the formation of cognitive maps and schemas. Their findings, published in Nature Neuroscience, suggest that during the formation of internal representations, the OFC and HC operate in parallel, as opposed to sequentially.

“Both the OFC and the hippocampus HC are implicated in the formation of cognitive maps and their generalization into schemas,” wrote Wenhui Zong, Jingfeng Zhou and their colleagues in their paper.

“However, how these areas interact in supporting this function remains unclear, with some proposals supporting a serial model in which the OFC draws on task representations created by the HC to extract key behavioral features and others suggesting a parallel model in which both regions construct representations that highlight different types of information.

“In the present study, we tested between these two models by asking how schema correlates in rat OFC would be affected by inactivating the output of the HC, after learning and during transfer across problems.”

To assess the validity of these two previously proposed models of schema formation, the researchers carried out a series of experiments involving adult rats. In these experiments, they recorded single-unit activity in the OFC using implanted electrons while the rats were completing tasks they were trained on and when they were applying knowledge they previously acquired to new problems.

Zong, Zhou and their colleagues also used experimental methods to inactivate the ventral subiculum, a neural pathway through which information leaves the HC that is known to project onto the OFC. The findings they collected offered evidence supporting the hypothesis that the OFC and HC operate in parallel to support the extraction of features that are used to form cognitive maps and schemas.

“We found that the prevalence and content of schema correlates were unaffected by inactivating one major HC output area, the ventral subiculum, after learning, whereas inactivation during transfer accelerated their formation,” wrote Zong, Zhou and their colleagues. “These results favor the proposal that the OFC and HC operate in parallel to extract different features defining cognitive maps and schemas.”

The results of this recent study contribute to the understanding of how the brains of rats, and potentially also humans, create internal representations that guide future decision-making, allowing them to apply knowledge acquired in the past to new problems. In the future, the recent work by Zong, Zhou and their colleagues could pave the way for further research to validate their observations or exploring them in greater detail.

© 2025 Science X Network