Leibniz Prize Recognizes Pioneering Work on the Brain's Navigational Code

Prof. Dr. Christian Doeller, Director of the Psychology Department at the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in Leipzig, Germany, has been awarded the prestigious Gottfried Wilhelm Leibniz Prize for 2026, one of Europe's highest research honors endowed with €2.5 million. This accolade celebrates his groundbreaking contributions to understanding the brain's navigational system, a neural mechanism that extends far beyond physical orientation to shape memory, learning, and abstract thinking.

Doeller's research reveals how specialized neurons, particularly grid cells in the entorhinal cortex (EC), form a metric framework for cognitive maps. These cells, first identified in rats, fire in a hexagonal grid pattern, providing a coordinate system for self-location independent of landmarks. His 2010 landmark study in Nature provided the first evidence of grid cell-like activity in humans using functional magnetic resonance imaging (fMRI) during virtual navigation tasks. This discovery bridged animal models and human cognition, positioning Germany at the forefront of European neuroscience.

From Spatial Navigation to the Cognitive Code of Thinking

The brain's navigational system, often dubbed the 'internal GPS,' involves a network of cell types: place cells in the hippocampus that activate at specific locations, grid cells in the EC for distance and direction measurement, and head-direction cells for orientation. Doeller's DoellerLab at MPI CBS has shown this system recodes spatial contexts into abstract categories, enabling flexible thinking and decision-making.

In experiments, participants navigate virtual environments like taxi simulations, where high performers—those finding optimal routes—exhibit peak activity in these regions. This spatial organization mirrors everyday cognition: sorting index cards by proximity or Luhmann's note system reflects neural metric spaces where similar concepts cluster. Doeller posits that 'space is a fantastic medium for visualizing similarities and dissimilarities,' linking navigation to knowledge abstraction.

Innovative Methods: Virtual Reality and Advanced Neuroimaging

Doeller's team employs cutting-edge techniques at MPI CBS, including fMRI, magnetoencephalography (MEG), and virtual reality (VR). Participants strapped into scanners play immersive games, mimicking real-world foraging or driving, while neural signals reveal grid patterns modulated by speed and direction.

• fMRI for macroscopic grid signals: Detects rotational symmetry in entorhinal and parietal regions, correlating with memory performance.
• VR paradigms: Landmark-free meadows or cityscapes test path integration and boundary vector cells.
• MEG for temporal dynamics: Tracks oscillations linking navigation to episodic memory replay.

These methods, refined over years, have validated animal findings in humans, with recent 2025 publications exploring hierarchical concepts and temporal mapping in the hippocampus.

Grid Cells in Humans: The 2010 Nature Breakthrough

In their seminal 2010 paper, Doeller, Barry, and Burgess used fMRI to observe a speed-modulated six-fold symmetry in a network spanning entorhinal/subicular, parietal, temporal, and prefrontal cortices. Strongest in the right EC, this signal aligned with rat grid properties, confirming humans use similar metric representations for spatial memory. The coherence across EC predicted navigation accuracy, implicating this system in autobiographical memory. Read the full study here.

This work earned Doeller an ERC Starting Grant and built his career from UCL postdoc to NTNU professor before MPI CBS in 2018.

Recent Insights: Stress Disrupts the Navigational Grid

Complementing Doeller's foundational research, a March 2026 study from Ruhr University Bochum reveals how acute stress via cortisol impairs grid cell function. In 40 men navigating VR meadows, cortisol blurred grid patterns, increasing errors especially sans landmarks, while boosting caudate compensation. Led by Dr. Osman Akan, this highlights vulnerability in Alzheimer's-prone entorhinal regions.

European collaboration thrives: Bochum's findings align with MPI CBS, underscoring Germany's neuroscience ecosystem.

Clinical Implications for Alzheimer's and Beyond

Entorhinal grid cells degenerate early in Alzheimer's disease (AD), preceding hippocampal atrophy. Doeller's MPI CBS is probing early AD and Long Covid via unpublished clinical VR studies, linking navigational deficits to memory loss. Spatial disorientation often signals preclinical AD, offering biomarkers.

Chronically stressed individuals face heightened dementia risk, as Bochum's cortisol effects mimic AD pathology. Interventions training spatial navigation could mitigate cognitive decline, with trials underway at European centers like Leipzig University, where Doeller holds an honorary professorship.

European Higher Education's Role in Neuroscience Excellence

Germany's Max Planck Society, with 86 institutes, exemplifies Europe's research prowess. MPI CBS Leipzig integrates psychology, linguistics, and neuroimaging, training PhDs via IMPRS programs. Doeller's Vice Presidency amplifies funding for cognitive neuroscience.

Collaborations span NTNU (Norway), Radboud (Netherlands), and UCL (UK), fostering EU-wide talent mobility under ERC and Horizon Europe. Ruhr Bochum's stress study reflects DFG-supported excellence, with Leibniz Prizes (€50M annually) fueling 10 winners yearly.

Broader Cognitive Applications: From Knowledge to Social Interaction

Doeller's hypothesis: navigation principles underpin 'cognitive code' for abstract spaces—semantic (word meanings), conceptual (hierarchies), temporal (event sequences). Recent papers map distances in concept space and prefrontal-hippocampal hierarchies.

• Hierarchical learning: EC/hippocampus parse nested structures.
• Social cognition: Planned dual-scanner studies on synchronized learning.
• Action planning: Maps link perception to motor sequences.

€2.5M enables hyperscanning for interpersonal navigation, revolutionizing social neuroscience.

Training the Next Generation at MPI CBS and Partners

MPI CBS hosts international PhDs, postdocs in DoellerLab, blending VR, AI analysis, and animal models. Leipzig's ecosystem—TU Dresden, Leipzig University—offers joint degrees, attracting global talent. Bochum's Cognitive Psychology trains via VR stress paradigms.

Europe's neuroscience pipeline thrives: 2025 saw DoellerLab publications on eye-tracking, predictive representations, emphasizing interdisciplinary skills for HE careers.

Photo by Sangga Rima Roman Selia on Unsplash

Future Outlook: Decoding the Brain's Universal Metric

Funded by Leibniz, Doeller eyes navigation's role in AI-inspired cognitive models and therapeutics. As Europe's neuroscience hub, Germany leads in translating grid insights to education (spatial learning curricula), therapy (VR rehab), and tech (neuromorphic computing).

This breakthrough underscores higher education's impact: MPI CBS alumni helm labs worldwide, perpetuating innovation. For researchers eyeing Europe's vibrant scene, opportunities abound in navigation, memory, and beyond.