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Cited by 828Memory and Neural MechanismsSpatial Cognition and NavigationVestibular and auditory disorders

Evidence for grid cells in a human memory network

Open access
Doeller, Christian F., Barry, Caswell, Burgess, Neil·2010·Nature
DOI 10.1038/nature08704PMC PMC3173857
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Abstract

Grid cells in the entorhinal cortex of freely moving rats provide a strikingly periodic representation of self-location which is indicative of very specific computational mechanisms. However, the existence of grid cells in humans and their distribution throughout the brain are unknown. Here we show that the preferred firing directions of directionally modulated grid cells in rat entorhinal cortex are aligned with the grids, and that the spatial organization of grid-cell firing is more strongly apparent at faster than slower running speeds. Because the grids are also aligned with each other, we predicted a macroscopic signal visible to functional magnetic resonance imaging (fMRI) in humans. We then looked for this signal as participants explored a virtual reality environment, mimicking the rats' foraging task: fMRI activation and adaptation showing a speed-modulated six-fold rotational symmetry in running direction. The signal was found in a network of entorhinal/subicular, posterior and medial parietal, lateral temporal and medial prefrontal areas. The effect was strongest in right entorhinal cortex, and the coherence of the directional signal across entorhinal cortex correlated with spatial memory performance. Our study illustrates the potential power of combining single-unit electrophysiology with fMRI in systems neuroscience. Our results provide evidence for grid-cell-like representations in humans, and implicate a specific type of neural representation in a network of regions which supports spatial cognition and also autobiographical memory.

AI snapshot

Written from the paper’s full text.

TL;DR

The paper combines rat single-unit recordings with human fMRI to argue that human entorhinal cortex contains grid-cell-like representations with 6-fold rotational symmetry in running direction. It reports that this directional signal is speed-modulated, appears in a wider spatial-memory network, and correlates with spatial memory performance.

Key findings

  • In rats, directionally modulated grid cells in medial entorhinal cortex had preferred firing directions aligned with the grid axes, and grid firing organization was more apparent during fast than slow running (17 male Lister hooded rats).
  • In humans, fMRI during virtual navigation showed speed-modulated 6-fold rotational symmetry in running direction; potential grid orientations were significantly clustered across voxels in 34/42 participants (Rayleigh test; population P<<0.00001, Monte Carlo simulation).
  • Whole-brain split-half analysis found significant activation in right entorhinal cortex for fast runs, with similar but slightly less reliable modulation in left entorhinal cortex; no other region reached whole-brain significance in that analysis. Coherence of right entorhinal grid orientations correlated with spatial memory performance.
  • 60° shifted directional adaptation was found in right entorhinal cortex extending into subiculum, posterior parietal, lateral temporal, and medial prefrontal cortices, and in medial parietal cortex; remote ROI sinusoidal responses reached significance in medial prefrontal (P=0.008), medial parietal (P=0.002), lateral temporal left (P=0.019) and right (P=0.0005), but not posterior parietal (P=0.058).

Methods

  • Rat single-unit recording: 17 male Lister hooded rats, medial entorhinal cortex recordings with a single microdrive carrying four tetrodes while animals foraged; grid cells identified by hexagonal spatial firing and assessed with a gridness measure.
  • Human fMRI: 42 male participants aged 18–31 (mean age 23.1 years), scanned on a 3T Siemens Allegra scanner, analyzed with SPM5; participants navigated a virtual reality grassy arena bounded by a cylindrical cliff, collected and replaced objects, and memory was measured as proximity of replacement location to the correct location.
  • Analysis: split-half design; quadrature filter identified 6-peaked sinusoidal modulation of signal by running direction to estimate grid orientation; whole-brain regressor cos(6[θ(t)–φ]) tested activation aligned with each participant’s mean grid orientation; adaptation regressors modeled log time since last running in the current direction.

Limitations

  • Stated: because fMRI can only measure effects of direction and speed, not location, the findings could reflect grid cells, or movement-related responses from head-direction or conjunctive directional grid cells, if they form coherent populations with 6-fold rotational symmetry.
  • Stated: responses in remote regions were weaker than in right entorhinal cortex and did not reach significance in the initial whole-brain split-half analysis; the posterior parietal ROI did not reach significance for the sinusoidal prediction (P=0.058).
  • Evident: the human sample consisted of 42 male participants aged 18–31, so generalizability to other sexes and broader age ranges is not established by the reported data.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/nature08704

Cites

38 of 38 references verified0 citation errors · 0 not checkable

Statistics

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Claims the paper makes

0 of 39 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Human fMRI activation and adaptation show a speed-modulated 6-fold rotational symmetry in running direction.

    “fMRI activation and adaptation showing a speed-modulated 6-fold rotational symmetry in running direction.”
    Quote in the paperSubstantial claim
  • Findingown data

    The spatial organization of grid cell firing is more strongly apparent at faster than slower running speeds.

    “the spatial organization of grid cell firing is more strongly apparent at faster than slower running speeds”
    • Also stated in: § Abstract · boosted
      “In addition, we show that the spatial organisation of grid cell firing is more strongly apparent during fast running than during slow running and immobility (Fig. 1d; see Methods for details and Supplementary Figs. 2-6 for further analyses and recording locations).”
    Quote in the paperSubstantial claim
  • Findingown data

    The speed-modulated 6-fold rotational symmetry signal was found in a network of entorhinal/subicular, posterior and medial parietal, lateral temporal and medial prefrontal areas.

    “The signal was found in a network of entorhinal/subicular, posterior and medial parietal, lateral temporal and medial prefrontal areas.”
    Quote in the paperSubstantial claim
  • Findingown data

    The effect was strongest in right entorhinal cortex.

    “The effect was strongest in right entorhinal cortex”
    Quote in the paperNot a substantial claim
  • Findingown data

    The preferred firing directions of directionally-modulated grid cells in rat entorhinal cortex are aligned with the grids.

    “Here we show that the preferred firing directions of directionally-modulated grid cells in rat entorhinal cortex are aligned with the grids”
    • Also stated in: § Abstract · plain
      “Here we show that the directions of modulation of conjunctive grid cells are aligned with the main axes of the grids (Fig. 1a-c).”
    Quote in the paperSubstantial claim
  • May combine two claims. 16
  • Classified as probably not a substantial claim. 4

  • May combine two claims.

    Findingown data

    Similar sinusoidal modulations were present in left entorhinal cortex, although slightly less reliably than on the right, and in the mean response of the entorhinal ROI.

    “Similar sinusoidal modulations were present in left entorhinal cortex, although slightly less reliably than on the right, and in the mean response of the entorhinal ROI (Supplementary Fig. 10).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The mean grid orientations in the 6-fold symmetry model varied randomly between participants, ruling out a role for specific visual features of the environment.

    “Consistent with grid cells, the mean grid orientations in the 6-fold symmetry model varied randomly between participants, ruling out a role for specific visual features of the environment (Supplementary Fig. 16).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The mean response to the sinusoidal regressor defined in entorhinal cortex in 8mm-radius ROIs centred on the locations of peak adaptation reached significance in medial prefrontal, medial parietal, and lateral temporal ROIs, but not in the posterior parietal ROI.

    “The responses in medial prefrontal (one-tailed t-test; P=0.008), medial parietal (P=0.002) and lateral temporal (left, P=0.019; right, P=0.0005) ROIs, but not the posterior parietal ROI (P=0.058), reached significance for this specific prediction.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Equivalent analyses for medium or slow runs, or looking for 4- or 8-fold or 5- or 7-fold rotational symmetry failed to show significant activation.

    “Equivalent analyses for medium or slow runs, or looking for 4- or 8-fold (Fig. 3b-c) or even 5- or 7-fold rotational symmetry (Supplementary Fig. 11) failed to show significant activation.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Significant adaptation to running direction occurred in visual cortex extending into posterior parahippocampal/lingual and retrosplenial cortices, with larger effects for fast than for slow runs.

    “We found significant adaptation to running direction in visual cortex extending into posterior parahippocampal/lingual and retrosplenial cortices, with larger effects for fast than for slow runs, see Fig. 4a-b.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Right entorhinal cortex (extending into subiculum) showed 60° shifted directional adaptation, independent of any effect of basic directional adaptation, as did regions in posterior parietal, lateral temporal and medial prefrontal cortices.

    “As predicted, right entorhinal cortex (extending into subiculum) showed 60° shifted directional adaptation, independent of any effect of basic directional adaptation, as did regions in posterior parietal, lateral temporal and medial prefrontal cortices, see Fig. 4c.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    No significant activation was found when the analyses applied to the entorhinal ROI were performed to control ROIs in the posterior right hippocampal location associated with memory performance in this task or the visual cortical location showing adaptation to running direction.

    “No significant activation was found when the analyses applied to the entorhinal ROI were performed to control ROIs in the posterior right hippocampal location associated with memory performance in this task11 or the visual cortical location showing adaptation to running direction (below), see Supplementary Fig. 12.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [11] Doeller, C. F., King, J. A. & Burgess, N. Parallel striatal and hippocampal systems for landmarks and boundaries in spatial memory. Proc. Natl Acad. Sci. USA 105, 5915–5920 (2008) source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisecitation

    Grid cells in medial entorhinal cortex of freely moving rodents fire whenever the animal traverses the vertices of an equilateral triangular grid covering the environment.

    “Grid cells recorded in medial entorhinal cortex of freely moving rodents fire whenever the animal traverses the vertices of an equilateral triangular grid covering the environment (see Fig. 1a), and may provide a neural substrate for path integration1-3,5,6.”
    Quote in the paperSubstantial claim0 of 5 sources checked
    • cites [1] Hafting, T., Fyhn, M., Molden, S., Moser, M. B. & Moser, E. I. Microstructure of a spatial map in the entorhinal cortex. Nature 436, 801–806 (2005) source

      Not checked in the free run.

    • cites [2] McNaughton, B. L., Battaglia, F. P., Jensen, O., Moser, E. I. & Moser, M. B. Path integration and the neural basis of the ‘cognitive map’. Nature Rev. Neurosci. 7, 663–678 (2006) source

      Not checked in the free run.

    • cites [3] Burgess, N., Barry, C. & O’Keefe, J. An oscillatory interference model of grid cell firing. Hippocampus 17, 801–812 (2007) source

      Not checked in the free run.

    • cites [5] Barry, C., Hayman, R., Burgess, N. & Jeffery, K. J. Experience-dependent rescaling of entorhinal grids. Nature Neurosci. 10, 682–684 (2007) source

      Not checked in the free run.

    • cites [6] Sargolini, F. et al. Conjunctive representation of position, direction, and velocity in entorhinal cortex. Science 312, 758–762 (2006) source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    During runs aligned with the grid, a smaller proportion of grid cells will fire but will do so at a higher rate, while more grid cells will be active during misaligned runs but at a lower rate.

    “During runs aligned with the grid, a smaller proportion of grid cells will fire but will do so at a higher rate, while more grid cells will be active during misaligned runs but at a lower rate (Supplementary Fig. 17).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    Human entorhinal cortex encodes virtual movement direction with 6-fold symmetry, consistent with a coherently-oriented population of grid cells similar to those found in rat entorhinal cortex and pre- and parasubiculum.

    “Our results provide the first evidence that human entorhinal cortex encodes virtual movement direction with 6-fold symmetry, consistent with a coherently-oriented population of grid cells similar to those found in rat entorhinal cortex1,5,6 and pre- and parasubiculum7.”
    Quote in the paperSubstantial claim0 of 4 sources checked
    • cites [1] Hafting, T., Fyhn, M., Molden, S., Moser, M. B. & Moser, E. I. Microstructure of a spatial map in the entorhinal cortex. Nature 436, 801–806 (2005) source

      Not checked in the free run.

    • cites [5] Barry, C., Hayman, R., Burgess, N. & Jeffery, K. J. Experience-dependent rescaling of entorhinal grids. Nature Neurosci. 10, 682–684 (2007) source

      Not checked in the free run.

    • cites [6] Sargolini, F. et al. Conjunctive representation of position, direction, and velocity in entorhinal cortex. Science 312, 758–762 (2006) source

      Not checked in the free run.

    • cites [7] Boccara, C. N. et al. Grid cells in presubiculum and parasubiculum. FENS Abstr 4, 128.21 (2008)

      Not checked in the free run.

    • Rests on an assumption: It is not known whether grid cells exist in humans, or how widespread the network of neurons with grid-like firing is.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Entorhinal cortex activation can predict memory performance.

    “This parallels findings that entorhinal cortex activation can predict memory performance12,13”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [12] Fernandez, G., Brewer, J. B., Zhao, Z., Glover, G. H. & Gabrieli, J. D. Level of sustained entorhinal activity at study correlates with subsequent cued-recall performance: a functional magnetic resonance imaging study with high acquisition rate. Hippocampus 9, 35–44 (1999) source

      Not checked in the free run.

    • cites [13] Olsen, R. K. et al. Performance-related sustained and anticipatory activity in human medial temporal lobe during delayed match-to-sample. J. Neurosci. 29, 11880–11890 (2009) source

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    The angular orientations of the grids relative to the environment appear constant across cells, whether neighbouring or farther apart, and rotate coherently when salient distal cues are rotated.

    “The angular orientations of the grids relative to the environment appears to be constant across cells, whether they are neighbouring1 or farther apart5 (Supplementary Fig. 1), and rotate coherently when salient distal cues are rotated1,6.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [1] Hafting, T., Fyhn, M., Molden, S., Moser, M. B. & Moser, E. I. Microstructure of a spatial map in the entorhinal cortex. Nature 436, 801–806 (2005) source

      Not checked in the free run.

    • cites [5] Barry, C., Hayman, R., Burgess, N. & Jeffery, K. J. Experience-dependent rescaling of entorhinal grids. Nature Neurosci. 10, 682–684 (2007) source

      Not checked in the free run.

    • cites [6] Sargolini, F. et al. Conjunctive representation of position, direction, and velocity in entorhinal cortex. Science 312, 758–762 (2006) source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    These results suggest a network of regions containing coherently aligned neural representations with 6-fold rotational symmetry, although the responses in remote regions were weaker than in right entorhinal cortex.

    “Overall, these results suggest a network of regions containing coherently aligned neural representations with 6-fold rotational symmetry, although the responses in remote regions were weaker than in right entorhinal cortex (e.g. not reaching significance in the initial whole-brain split-half analysis), possibly reflecting a lower concentration of grid-like cells.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The rate and inter-burst frequency of grid cell firing and the frequency with which individual firing fields in a grid are sampled increase with running speed.

    “the rate6 and inter-burst frequency10 of grid cell firing and the frequency with which individual firing fields in a grid are sampled increase with running speed.”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [6] Sargolini, F. et al. Conjunctive representation of position, direction, and velocity in entorhinal cortex. Science 312, 758–762 (2006) source

      Not checked in the free run.

    • cites [10] Jeewajee, A., Barry, C., O’Keefe, J. & Burgess, N. Grid cells and theta as oscillatory interference: electrophysiological data from freely moving rats. Hippocampus 18, 1175–1185 (2008) source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    The adaptation effect is also consistent with view-specific single unit responses in humans or with the presence of head-direction cells which have been reported in retrosplenial cortex.

    “It is also consistent with view-specific single unit responses in humans18 or with the presence of head-direction cells19 which have been reported in retrosplenial cortex20.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [18] Ekstrom, A. D. et al. Cellular networks underlying human spatial navigation. Nature 425, 184–188 (2003) source

      Not checked in the free run.

    • cites [19] Taube, J. S. Head direction cells and the neuropsychological basis for a sense of direction. Prog. Neurobiol. 55, 225–256 (1998) source

      Not checked in the free run.

    • cites [20] Chen, L. L., Lin, L. H., Green, E. J., Barnes, C. A. & McNaughton, B. L. Head-direction cells in the rat posterior cortex. I. Anatomical distribution and behavioral modulation. Exp. Brain Res. 101, 8–23 (1994) source

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Interpretationreasoning

    Because only effects of direction and speed (not location) can be measured in the fMRI signal, the findings could reflect the presence of grid cells, or movement-related responses from head-direction, or conjunctive directional grid cells, if they form coherent populations whose firing has 6-fold rotational symmetry.

    “Because we can only measure effects of direction and speed (not location) in the fMRI signal, our findings could reflect the presence of grid cells, or movement-related responses from head-direction19, or ‘conjunctive’ directional grid6,7 cells, if they form coherent populations whose firing has 6-fold rotational symmetry.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [19] Taube, J. S. Head direction cells and the neuropsychological basis for a sense of direction. Prog. Neurobiol. 55, 225–256 (1998) source

      Not checked in the free run.

    • cites [6] Sargolini, F. et al. Conjunctive representation of position, direction, and velocity in entorhinal cortex. Science 312, 758–762 (2006) source

      Not checked in the free run.

    • cites [7] Boccara, C. N. et al. Grid cells in presubiculum and parasubiculum. FENS Abstr 4, 128.21 (2008)

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    These results outline a circuit for navigation, consistent with suggestions that medial and lateral temporal, posterior and medial parietal and medial prefrontal areas cooperate to support spatial cognition, and implicate a specific type of underlying neural representation.

    “These results outline a circuit for navigation, consistent with suggestions that medial and lateral temporal, posterior and medial parietal and medial prefrontal areas cooperate to support spatial cognition2,8,11,21,22, and implicate a specific type of underlying neural representation.”
    Quote in the paperSubstantial claim0 of 5 sources checked
    • cites [2] McNaughton, B. L., Battaglia, F. P., Jensen, O., Moser, E. I. & Moser, M. B. Path integration and the neural basis of the ‘cognitive map’. Nature Rev. Neurosci. 7, 663–678 (2006) source

      Not checked in the free run.

    • cites [8] Whitlock, J. R., Sutherland, R. J., Witter, M. P., Moser, M. B. & Moser, E. I. Navigating from hippocampus to parietal cortex. Proc. Natl Acad. Sci. USA 105, 14755–14762 (2008) source

      Not checked in the free run.

    • cites [11] Doeller, C. F., King, J. A. & Burgess, N. Parallel striatal and hippocampal systems for landmarks and boundaries in spatial memory. Proc. Natl Acad. Sci. USA 105, 5915–5920 (2008) source

      Not checked in the free run.

    • cites [21] Byrne, P., Becker, S. & Burgess, N. Remembering the past and imagining the future: a neural model of spatial memory and imagery. Psychol. Rev. 114, 340–375 (2007) source

      Not checked in the free run.

    • cites [22] Wolbers, T., Wiener, J. M., Mallot, H. A. & Buchel, C. Differential recruitment of the hippocampus, medial prefrontal cortex, and the human motion complex during path integration in humans. J. Neurosci. 27, 9408–9416 (2007) source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    The observed grid-like representations support spatial memory and are found in a circuit of regions which strikingly overlaps the network for autobiographical memory and imagery.

    “The observed grid-like representations support spatial memory (Fig. 3f) and are found in a circuit of regions which strikingly overlaps the network for autobiographical memory and imagery, e.g. refs.21,23,24.”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [21] Byrne, P., Becker, S. & Burgess, N. Remembering the past and imagining the future: a neural model of spatial memory and imagery. Psychol. Rev. 114, 340–375 (2007) source

      Not checked in the free run.

    • cites [23] Maguire, E. A. Neuroimaging studies of autobiographical event memory. Phil. Trans. R. Soc. Lond. B 356, 1441–1451 (2001) source

      Not checked in the free run.

    • cites [24] Schacter, D. L., Addis, D. R. & Buckner, R. L. Remembering the past to imagine the future: the prospective brain. Nature Rev. Neurosci. 8, 657–661 (2007) source

      Not checked in the free run.

18 of 18

  • The paper relies on this without support.

    It is not known whether grid cells exist in humans, or how widespread the network of neurons with grid-like firing is.

    “However, it is not known whether or not grid cells exist in humans, or how widespread the network of neurons with grid-like firing is, although the pre- and para-subiculum7 and posterior parietal cortex8 have been implicated.”
1 of 1

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Cites

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Research works printed but not linked: 2

  1. Boccara, C. N. et al. Grid cells in presubiculum and parasubiculum. FENS Abstr 4, 128.21 (2008)
  2. Recce, M. & O’Keefe, J. The tetrode: a new technique for multiunit extracellular recording. Soc. Neurosci. Abstr. 15, 1250 (1989)

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Related

Authors
Doeller, C. F., Barry, C., & Burgess, N.
Affiliations
  • University College London (GB)
  • UCL Queen Square Institute of Neurology (GB)
Corresponding author
  • Doeller, Christian F.
  • Burgess, Neil
ORCID
Venue
Nature
Publisher
Springer Science and Business Media LLC
Published
2010-01-20
Volume
463
Issue
7281
Pages
657-661
ISSN
  • 0028-0836 (ISSN-L)
  • 1476-4687
DOI
10.1038/nature08704
PMC
PMC3173857
OpenAlex
W2081197259
Cited by
828
References
38
Citations by year
2026: 59 · 2025: 54 · 2024: 64 · 2023: 86 · 2022: 61 · 2021: 70 · 2020: 67 · 2019: 52 · 2018: 55 · 2017: 42 · 2016: 41 · 2015: 33 · 2014: 24 · 2013: 39 · 2012: 31
FWCI
23.21
Type
journal article
Language
en
Open access
Licence
www.springer.com/tdm (tdm)
Locations
  • Nature (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
  • UCL Discovery (University College London) (submittedVersion)
  • MPG.PuRe (Max Planck Society) (submittedVersion)
Funders
  • Wellcome Trust
  • European Commission
  • Medical Research Council
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
  • Physical Sciences › Engineering › Automotive Engineering › Spatial Cognition and Navigation
  • Life Sciences › Neuroscience › Neurology › Vestibular and auditory disorders
Keywords
grid cells, entorhinal cortex, virtual reality navigation, spatial orientation, parietal cortex, prefrontal cortex, temporal lobe, single-unit recording, fMRI signal, spatial cognition, coherence analysis
MeSH terms
Action Potentials, Adaptation, Physiological, Adolescent, Adult, Animals, Humans, Logic, Magnetic Resonance Imaging, Male, Memory, Neurons, Orientation, Running, Space Perception, User-Computer Interface, Entorhinal Cortex, Rats, Young Adult

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