Bonn, June 2026 – How does the brain integrate new information on familiar routes without redrawing its entire spatial map? Researchers at the University Hospital Bonn (UKB) and the University of Bonn have found an elegant solution.
In a mouse study, the team showed that the hippocampus does not overwrite its stable spatial maps. Instead, it adds new information as separate layers – much like annotations in a navigation app that mark obstacles or events without changing the underlying route.
When mice encountered unexpected air puffs on a familiar track, the CA3 circuits created a new “annotation” while the original spatial map remained fully intact. This dual-layer system allows the brain to preserve core spatial knowledge while flexibly encoding new experiences.
“It’s as if the hippocampus uses a version control system,” explains co-senior author Prof. Heinz Beck.
The findings, published in PNAS, provide important insights into how the brain balances stability and flexibility – with potential relevance for memory disorders and neurological conditions.
Original publication: Miguel-López et al. (2026): Transformations of the spatial activity manifold convey aversive information in CA3. PNAS. DOI: 10.1073/pnas.2517639123