The Nobel Prize in Physiology or Medicine 2014 was awarded to John O’Keefe and, jointly, to May-Britt Moser and Edvard Moser for their discoveries of cells that constitute a positioning system in the brain. The Nobel committee described it as an inner GPS that makes it possible to orient ourselves in space, and as a demonstration of a cellular basis for higher cognitive function. It is one of the rare cases where a specific, elegant mechanism was found underneath something as abstract as knowing where you are.

What Are Place Cells?

In 1971 John O’Keefe found that certain nerve cells in the hippocampus fired reliably whenever a rat occupied a particular location in a room. Move the animal elsewhere and a different cell fired. He concluded that these place cells formed a map of the room.

The striking part is what they are not. A place cell is not responding to a visual scene or a landmark. It fires for a position — an abstract location within a represented space — and continues to do so in darkness.

This was the first concrete evidence that the brain constructs an internal model of external space rather than simply processing incoming sensation. It represents where you are, and that representation persists whether or not you can currently see anything.

What Did the Mosers Add?

More than three decades later, in 2005, May-Britt and Edvard Moser identified a different cell type in the entorhinal cortex, which feeds into the hippocampus. They called them grid cells.

Grid cells generate a coordinate system that allows precise positioning and pathfinding. Each fires not at one location but at many, arranged in a strikingly regular triangular lattice across the environment — the closest thing to graph paper anyone has found in a brain.

Together, hippocampal place cells and entorhinal grid cells form interconnected networks critical for computing spatial maps and performing navigational tasks. Grid cells supply the metric framework — the sense of distance and direction — while place cells mark specific positions within it.

The system includes other specialists too: head direction cells acting as a compass, and border cells responding to environmental boundaries.

Why Is This in the Memory Region?

This is the genuinely interesting question, because the hippocampus was already famous for memory long before anyone found place cells in it.

The current understanding is that these are not two separate jobs. Episodic memory — recall of specific events — is fundamentally organised by context, and place and time are the primary contextual dimensions. Remembering an event means reconstructing where and when it occurred.

The spatial machinery appears to provide the scaffolding that memory is hung on. This explains why memories are so often anchored to locations, why returning to a place can retrieve detail you could not access otherwise, and why the method of loci — mentally placing items along a familiar route — is such an effective memory technique. It exploits a system built for exactly that.

It also explains a clinical pattern. Because the same structures serve both functions, conditions affecting the hippocampus tend to produce spatial disorientation and memory difficulty together. Getting lost in familiar surroundings is often an early sign in Alzheimer’s disease, and the entorhinal cortex — where grid cells live — is among the first regions affected.

Does GPS Use Weaken This System?

There is a plausible mechanism and less conclusive evidence than the headlines suggest, which is worth stating honestly.

The mechanism is straightforward. Turn-by-turn navigation lets you follow instructions without constructing a spatial model. You never have to build or consult the map, so the system that builds maps gets less use. Given that plasticity reinforces what is practiced, reduced use plausibly means reduced capacity.

Research has found differences in hippocampal engagement between people navigating from memory and people following directions, and studies of navigation experts have found structural differences associated with extensive spatial practice. That is consistent with a use-dependent system.

What has not been established is that ordinary GPS use causes meaningful long-term decline in everyday navigation ability, let alone broader cognitive harm. The honest position: the system is use-dependent, occasionally navigating without assistance is reasonable, and the alarming versions of this claim outrun the data.

Why Do Some People Get Lost Constantly?

Individual variation in spatial ability is large and largely normal. Some people build and maintain detailed cognitive maps easily; others rely on route memory — a sequence of turns rather than a model of the space. Route strategies work well until something changes.

Sleep and stress both affect this more than people expect. Hippocampal function is sensitive to both, and someone who is sleep-deprived or under sustained stress will genuinely navigate less well. Spatial confusion during a difficult period is not imagination.

Attention matters too. Building a spatial model requires attending to the environment while moving through it, and someone whose attention is consumed by threat monitoring or rumination is not encoding the route, which is why anxiety so often shows up as forgetfulness.

What warrants medical evaluation is change rather than baseline difficulty. Someone who has always been poor with directions is describing a trait. Someone who has become disoriented in familiar places, particularly with other memory changes, should be assessed — see can we slow brain aging.

Can Spatial Ability Be Improved?

Within limits, and the honest framing is practice rather than transformation. The system is use-dependent, so navigating deliberately — noticing landmarks, forming a sense of overall layout, occasionally finding your way without assistance — exercises it.

The broader supports matter as much. Sleep is when hippocampal consolidation occurs, including consolidation of spatial learning. Aerobic exercise is directly relevant here, given the randomized trial in which a year of it increased anterior hippocampal volume in older adults and improved spatial memory specifically.

That last point is worth emphasising, because it connects this to something actionable. The structure housing your internal GPS responds measurably to walking — which is a pleasing symmetry. Our article on how exercise changes the brain covers the mechanism.

Where sustained stress or disrupted regulation is degrading hippocampal function, addressing that is relevant too — brain mapping shows what the current pattern looks like, and LENS neurofeedback therapy works on it directly.