Researchers used virtual reality and high-resolution fMRI to map how the hippocampus and connected cortex distinguish novel from familiar places. They identified a gradient along the hippocampus — head regions favoring familiarity and tail regions responding to novelty — and a cone-shaped novelty–familiarity pattern in cortex. Different large-scale networks activate for novel versus known locations, a division that may help explain early navigation problems in Alzheimer’s disease.
Brain 'Dial' That Stops Us Getting Lost — Hippocampus Shifts From Novelty to Familiarity
Scientists ran brain scans to understand the organization of cells that respond to familiar places and to new places. | Credit: Andrew Brookes/Getty Images
Scientists have identified a functional "dial" in the human brain that becomes more active when we explore unfamiliar places — a discovery that helps explain why getting lost is often an early sign of dementia such as Alzheimer’s disease.
Using high-resolution functional MRI combined with virtual reality (VR), researchers mapped how the hippocampus and connected cortical regions respond when people navigate both known and novel environments. The study, published Dec. 4 in Nature Communications, tested 56 healthy volunteers aged 20–37 who searched a VR grassy field ringed by mountains for six hidden items while their brain activity was recorded.
Study Design and Methods
Participants navigated a VR world inside an MRI scanner while researchers monitored blood flow changes that indicate neural activity. The task reproduced real exploratory behavior so investigators could compare brain responses to familiar versus unfamiliar locations. The team focused on the hippocampus — a seahorse-shaped structure essential for memory and spatial navigation — and nearby cortical regions.
Hippocampal "Dial": A Novelty–Familiarity Gradient
The researchers found a systematic gradient along the long axis of the hippocampus. Cells near the hippocampal head tended to activate when participants revisited familiar locations, while cells toward the tail preferentially responded to novel places. In other words, as you move from one end of the hippocampus to the other, there is a progressive shift from familiarity-preferring activity to novelty-preferring activity.
"You could see that there's this shift in level of novelty versus familiarity as you go from one end to the other," said co-author Deniz Vatansever.
Cortical Pattern And Large-Scale Networks
Beyond the hippocampus, the team identified a cone-shaped novelty–familiarity organization in a cortical region: core subregions preferred familiar places, with increasing novelty preference toward the periphery. The study also showed that familiar locations engaged large-scale networks tied to memory and motor control, while novel locations activated networks involved in attention and perception. The authors suggest this division may let the brain switch between learning about new surroundings and efficiently navigating known routes.
Implications For Dementia And Memory
These novelty–familiarity gradients appear in brain areas that are among the first affected by Alzheimer’s disease. Because navigation and episodic memory (recall of specific events) share neural circuitry, disruptions to these gradients could help explain why spatial disorientation and memory loss emerge early in dementia. Mapping these patterns could ultimately contribute to early biomarkers for cognitive decline.
What This Means
This study refines our understanding of how the brain encodes place and novelty. By combining VR with high-resolution fMRI, researchers revealed an orderly neural mechanism that helps us detect new environments and rely on familiar ones — a mechanism with clear relevance to aging and neurological disease.
Study Source: Vatansever et al., Nature Communications, published Dec. 4. Participants: 56 healthy adults, ages 20–37. Method: VR navigation task during functional MRI.
