# Time Makes Space: Emergence of Place Fields in Networks Encoding Temporally Continuous Sensory Experiences

arXiv: https://arxiv.org/abs/2408.05798 · HTML: https://mlsanity.com/paper/2408.05798/

## Key facts

- Cited by 4 papers in the map (data through 14 Oct 2026).
- Builds on 5 of its 69 references that are in the map.
- First posted on arXiv 11 Aug 2024.

## Builds on (most cited first, 5 of 5)

- [Attractor and integrator networks in the brain](https://mlsanity.com/paper/2112.03978/) (2021)
- [Emergence of grid-like representations by training recurrent neural networks to perform spatial localization](https://mlsanity.com/paper/1803.07770/) (2018)
- [Space is a latent sequence: Structured sequence learning as a unified theory of representation in the hippocampus](https://mlsanity.com/paper/2212.01508/) (2022)
- [A geometric attractor mechanism for self-organization of entorhinal grid modules](https://mlsanity.com/paper/1806.00975/) (2018)
- [Dynamic self-organized error-correction of grid cells by border cells](https://mlsanity.com/paper/1808.01503/) (2018)

## Built on by (most cited first, 4 of 4)

- [REMI: Reconstructing Episodic Memory During Internally Driven Path Planning](https://mlsanity.com/paper/2507.02064/) (2025)
- [Emergence of Spatial Representation in an Actor-Critic Agent with Hippocampus-Inspired Sequence Generator](https://mlsanity.com/paper/2510.09951/) (2025)
- [When and Where: A Model Hippocampal Network Unifies Formation of Time Cells and Place Cells](https://mlsanity.com/paper/2604.00036/) (2026)
- [Exploratory Experience Shapes the Geometry of Predictive Representations](https://mlsanity.com/paper/2605.27929/) (2026)

## Abstract (arXiv)

The vertebrate hippocampus is believed to use recurrent connectivity in area CA3 to support episodic memory recall from partial cues. This brain area also contains place cells, whose location-selective firing fields implement maps supporting spatial memory. Here we show that place cells emerge in networks trained to remember temporally continuous sensory episodes. We model CA3 as a recurrent autoencoder that recalls and reconstructs sensory experiences from noisy and partially occluded observations by agents traversing simulated rooms. The agents move in realistic trajectories modeled from rodents and environments are modeled as high-dimensional sensory experience maps. Training our autoencoder to pattern-complete and reconstruct experiences with a constraint on total activity causes spatially localized firing fields, i.e., place cells, to emerge in the encoding layer. The emergent place fields reproduce key aspects of hippocampal phenomenology: a) remapping (maintenance of and reversion to distinct learned maps in different environments), implemented via repositioning of experience manifolds in the network's hidden layer, b) orthogonality of spatial representations in different arenas, c) robust place field emergence in differently shaped rooms, with single units showing multiple place fields in large or complex spaces, and d) slow representational drift of place fields. We argue that these results arise because continuous traversal of space makes sensory experience temporally continuous. We make testable predictions: a) rapidly changing sensory context will disrupt place fields, b) place fields will form even if recurrent connections are blocked, but reversion to previously learned representations upon remapping will be abolished, c) the dimension of temporally smooth experience sets the dimensionality of place fields, including during virtual navigation of abstract spaces.