Publications

in press

McAvan A.S., Wank A., Rapcsak S.Z., Grilli M. & Ekstrom A.D. (in press). Largely intact memory for spatial locations during navigation in an individual with dense amnesia. Neuropsychologia.

2021

Zheng, L., Gao, Z., McAvan, A. S., Isham, E. A., & Ekstrom, A. D. (2021). Partially overlapping spatial environments trigger reinstatement in hippocampus and schema representations in prefrontal cortex. Nature Communications, 12(1), 6231. https://doi.org/10.1038/s41467-021-26560-w

Liang, M., Zheng, J., Isham, E., & Ekstrom, A. (2021). Common and Distinct Roles of Frontal Midline Theta and Occipital Alpha Oscillations in Coding Temporal Intervals and Spatial Distances. Journal of Cognitive Neuroscience, 33(11), 2311–2327. https://doi.org/10.1162/jocn_a_01765

Preciado, C. E., Starrett, M. J., & Ekstrom, A. D. (2021). Assessment of a short, focused training to reduce symptoms of cybersickness. Presence, 27(4), 361-377. https://doi.org/10.1162/pres_a_00335

Ekstrom A.D. (2021). Regional variation in neurovascular coupling and why we still lack a Rosetta Stone. Philosophical Transactions of the Royal Society, 376, 20190634. http://dx.doi.org/10.1098/rstb.2019.0634 [pdf]

2020

Starrett, M. J., McAvan, A. S., Huffman, D. J., Stokes, J. D., Kyle, C. T., Smuda, D. N., Kolarik, B. S., Laczko, J., & Ekstrom A. D. (in press). Landmarks: A solution for spatial navigation and memory experiments in virtual reality. Behavior Research Methods. [Open Access Article]

Ekstrom A.D. & Yonelinas A.P. (2020). Precision, binding, and the hippocampus: Precisely what are we are talking about? Neuropsychologia, 138, 107341. https://doi.org/10.1016/j.neuropsychologia.2020.107341

Harootonian SK, Wilson RC, Hejtmánek L, Ziskin EM, Ekstrom AD (2020) Path integration in large-scale space and with novel geometries: Comparing vector addition and encoding-error models. PLOS Computational Biology 16(5): e1007489. [pdf]

Ekstrom A.D. (2020). Cognitive neuroscience: Why do we get lost when we are stressed? Current Biololgy, 30, R430-R450. [pdf]

Hejtmanek L., Starrett M., Ferrer E. & Ekstrom A.D. (2020). How much of what we learn in virtual reality transfers to real-world navigation? Multisensory Research, 1-25. doi:10.1163/22134808-20201445

2019

Huffman D.J. & Ekstrom A.D. (2019). A modality-independent network underlies retrieval of large-scale spatial environments in the human brain. Neuron, 104(3):611-622.e7. [pdf]

Ekstrom A.D., Harootonian S.K. & Huffman D.L. (2019). Commentary: Grid coding, spatial representation, and navigation: Should we assume an isomorphism? Hippocampus, 1-11. [pdf]

Izadi A., Pevzner A., Lee D.J., Ekstrom A.D., Shahlaie K., Gurkoff G.G. (2019). Medial Septal Stimulation Increases Seizure Threshold and Improves Cognition in Epileptic Rats. Brain Stimulation, 12(3), 735-742. doi:10.1016/j.brs.2019.01.005

Yonelinas A.P., Ranganath C.R., Ekstrom A.D. & Wiltgen B.L. (2019). A Contextual Binding Theory of Episodic Memory: Systems Consolidation Reconsidered. Nature Reviews Neuroscience, 20(6), 364-375. doi:10.1038/s41583-019-0150-4

Kyle C.T., Stokes J.D., Bennett J., Meltzer J. Permenter M.R., Voyt J.A., Ekstrom A.D. and Barnes C.A. (2019). Cytoarchitectonically-driven MRI atlas of nonhuman primate hippocampus: preservation of subfield volumes in aging. Hippocampus, 29(5), 409-421. doi:10.1002/hipo.22809

Peacock, C. E. & Ekstrom, A. D. (2019). Verbal cues flexibly transform spatial representations in human memory. Memory, 27(4), 465-479. doi: 10.1080/09658211.2018.1520890 [accepted manuscript]

Starrett, M. J., Stokes, J. D., Huffman, D. J., Ferrer, E., & Ekstrom, A. D. (2019). Learning-dependent evolution of spatial representations in large-scale virtual environments. Journal of Experimental Psychology: Learning, Memory, and Cognition, 45(3), 497-514. doi:10.1037/xlm0000597 [accepted manuscript]

Schedlbauer, A.M. & Ekstrom, A. D. (2019). Flexible network community organization during encoding and retrieval of spatiotemporal episodic memories. Network Neuroscience, 3(4), 10710-1093. [pdf]

2018

Huffman D.J. & Ekstrom A.D. (2018). Which way is the bookstore? A closer look at the judgments of relative directions task. Spatial Cognition and Computation. 1-37.

Starrett, M. J., & Ekstrom, A. D. (2018). Perspective: Assessing the flexible acquisition, integration, and deployment of human spatial representations and information. Frontiers in Human Neuroscience, 12(281). doi:10.3389/fnhum.2018.00281 [pdf]

Liang, M., Starrett, M. J., & Ekstrom, A. D. (2018). Dissociation of frontal-midline delta-theta and posterior alpha oscillations: A mobile EEG study. Psychophysiology, 55:e13090. doi:10.1111/psyp.13090 [pdf]

Kim, K, Schedlbauer, A, Rollo, M, Karunakaran, S, Ekstrom AD, & Tandon, N. (2018). Network-based brain stimulation selectively impairs spatial retrieval. Brain Stimulation, 11(1): 213-221. doi:10.1016/j.brs.2017.09.016 [pdf]

Kolarik, BS, Baer, T, Shahalaie, K, Yonelinas, AP, & Ekstrom, AD (2018). Close but no cigar: Spatial precision deficits following medial temporal lobe lesion s provide novel insight into theoretical models of navigation and memory. Hippocampus 28(1): 31-41. doi:10.1002/hipo.22801 [pdf]

Dimsdale-Zucker, H. R., Ritchey, M., Ekstrom, A. D., Yonelinas, A. P., & Ranganath, C. (2018). CA1 and CA3 differentially support spontaneous retrieval of episodic contexts within human hippocampal subfields. Nature Communications, 9(1). doi:10.1038/s41467-017-02752-1 [pdf]

Bouffard, N, Stokes, JD, Dramer, HJ, & Ekstrom, AD. (2018). Temporal encoding strategies result in boosts to final free recall comparable to spatial ones. Memory and Cognition 46(1): 17-31. doi:10.3758/s13421-017-0742-z [pdf]

2017

Ekstrom, AD, Huffman, DJ, & Starrett, M. (2017). Interacting networks of brain regions underlie human spatial navigation: A review and novel synthesis of the literature. Journal of Neurophysiology, 188(6): 3328-3344. doi:10.1152/jn.00531.2017 pdf

Ekstrom, AD, & Ranganath, C. (2017). Space, time, and episodic memory: The hippocampus is all over the cognitive map. Hippocampus. doi:10.1002/hipo.22750 [epub ahead of print] pdf

Ekstrom, AD, & Isham, EA. (2017). Human spatial navigation: representations across dimensions and scales. Current Opinion in Behavioral Science, 17, 84-89. doi:10.1016/j.cobeha.2017.06.005 pdf

Bohbot VD, Copara MS, Gotman J, & Ekstrom AD. (2017). Low-frequency theta oscillations in the human hippocampus during real-world and virtual navigation. Nature Communications, 8, 14415. DOI: 10.1038/ncomms14415. pdf

Lieberman JS, Kyle CT, Schedlbauer A, Stokes J, & Ekstrom AD. (2017). A Tale of Two Temporal Coding Strategies: Common and Dissociable Brain Regions Involved in Recency versus Associative Temporal Order Retrieval Strategies. Journal of Cognitive Neuroscience, 29(4), 739-754. DOI: 10.1162/jocn_a_01081. pdf

2016

Arnold AE, Iaria G, & Ekstrom AD. (2016). Mental simulation of routes during navigation involves adaptive temporal compression. Cognition, 157, 14-23. doi: 10.1016/j.cognition.2016.08.009 pdf

Kim K, Ekstrom AD, & Tandon N. (2016). A network approach for modulating memory processes via direct and indirect brain stimulation: Toward a causal approach for the neural basis of memory. Neurobiology of Learning and Memory, 134 Pt. A, 162-177. DOI: http://dx.doi.org/10.1016/j.nlm.2016.04.001 pdf

Kolarik BS, Shahlaie K, Hassan A, Borders AA, Kaufman KC, Gurkoff GE, Yonelinas AP, & Ekstrom AD. (2016). Impairments in precision, rather than spatial strategy, characterize performance on the virtual Morris water maze: a case study. Neuropsychologia, 80, 90-101. DOI: 10.1016/j.neuropsychologia.2015.11.013 pdf

Vass LK, Copara MS, Seyal M, Shahlaie K, Tomaszewski Farias S, Shen PY, & Ekstrom AD. (2016). Oscillations Go the Distance: Low-Frequency Human Hippocampal Oscillations Code Spatial Distance in the Absence of Sensory Cues during Teleportation. Neuron, 89(6), 1180-1186. DOI: 10.1016/j.neuron.2016.01.045 Article: pdf Supplement: pdf

2015

Ekstrom AD. Why vision is important to how we navigate. (2015). Hippocampus, 25(6), 731-735. DOI: 10.1002/hipo.22449 pdf

Kyle CT, Smuda DN, Hassan AS, & Ekstrom AD. (2015). Roles of human hippocampal subfields in retrieval of spatial and temporal context. Behavioral Brain Research, 278, 549-558. DOI: 10.1016/j.bbr.2014.10.034 pdf

Kyle CT, Stokes JD, Lieberman JS, Hassan AS, & Ekstrom AD. (2015). Successful retrieval of competing spatial environments in humans involves hippocampal pattern separation mechanisms. eLife, 4, e10499. pdf

Stokes J, Kyle C, & Ekstrom AD. (2015). Complementary roles of human hippocampal subfields in differentiation and integration of spatial context. Journal of Cognitive Neuroscience, 27(3), 546–559. doi: 10.1162/jocn_a_00736 pdf

Suthana NA, Parikshak NN, Ekstrom AD, Ison MJ, Knowlton BJ, Bookheimer SY, & Fried I. (2015). Specific responses of human hippocampal neurons are associated with bedtter memory. Proceedings of the National Academy of Sciences, 112(33), 10503-10508. DOI: 10.1073/pnas.1423036112 pdf

Watrous AJ, Fell J, Ekstrom AD, & Axmacher, N. (2014). More than spikes: common oscillatory mechanisms for content specific neural representations during perception and memory. Current Opinion in Neurobiology, 31C, 33–39. DOI: 10.1016/j.conb.2014.07.024 pdf

Yushkevich PA, Amaral RSC, Augustinack JC, Bender AR, Bernstein JD, … Ekstrom A, … Zeineh MM. (2015). Quantitative comparison of 21 protocols for labeling hippocampal subfields and parahippocampal subregions in in vivo MRI: towards a harmonized segmentation protocol. Neuroimage, 111, 526-541. DOI: 10.1016/j.neuroimage.2015.01.004 pdf

2014

Copara MS, Hassan AS, Kyle CT, Libby LA, Ranganath C, & Ekstrom AD. (2014). Complementary roles of human hippocampal subregions during retrieval of spatiotemporal context. Journal of Neuroscience, 34(20), 6834–6842. DOI: 10.1523/JNEUROSCI.5341-13.2014 pdf

Ekstrom AD. (2014). Cognitive neuroscience: navigating human verbal memory. Current Biology, 24(4), R167–R168. DOI: 10.1016/j.cub.2013.12.043 pdf

Ekstrom AD, Arnold AEGF, & Iaria G. (2014). A critical review of the allocentric spatial representation and its neural underpinnings: toward a network-based perspective. Frontiers in Human Neuroscience, 8:803. DOI: 10.3389/fnhum.2014.00803 pdf

Ekstrom AD & Watrous AJ. (2014). Multifaceted roles for low-frequency oscillations in bottom-up and top-down processing during navigation and memory. Neuroimage 85(Pt 2), 667-677. DOI: 10.1016/j.neuroimage.2013.06.049 pdf

Schedlbauer AM, Copara MS, Watrous AJ, & Ekstrom AD. (2014). Multiple interacting brain areas underlie successful spatiotemporal memory retrieval in humans. Scientific Reports, 4, 6431. DOI: 10.1038/srep06431 pdf

Watrous AJ & Ekstrom AD. (2014). The spectro-contextual encoding and retrieval theory of episodic memory. Frontiers in Human Neuroscience, 8:75. DOI: 10.3389/fnhum.2014.00075 pdf

Zhang H, Zherdeva K, & Ekstrom AD. (2014). Different “routes” to a cognitive map: dissociable forms of spatial knowledge derived from route and cartographic map learning. Memory & Cognition, 42(7), 1106–1117. DOI: 10.3758/s13421-014-0418-x pdf

2013

Gruber MJ, Watrous AJ, Ekstrom AD, Ranganath C, & Otten LJ. (2013). Expected reward modulated encoding-related theta activity before an event. Neuroimage, 64, 68-74. DOI: 10.1016/j.neuroimage.2012.07.064 pdf

Lee DJ, Gurkoff GG, Izadi A, Berman RF, Ekstrom AD, Muizelaar P, Lyeth BG, & Shahlaie K. (2013). Medial septal nucleus theta frequency deep brain stimulation improves spatial working memory following traumatic brain injury. Journal of Neurotrauma, 30(2), 131-139. DOI: 10.1089/neu.2012.2646 pdf

Watrous AJ, Lee DJ, Izadi A, Gurkoff GG, Shahlaie K, & Ekstrom AD. (2013). A comparative study of human and rat hippocampal low frequency oscillations during spatial navigation. Hippocampus, 23(8), 656-661. DOI: 10.1002/hipo.22124 pdf

Watrous AJ, Tandon N, Connor CR, Pieters T, & Ekstrom AD.(2013). Frequency-specific increases in network connectivity underlie successful spatiotemporal memory retrieval. Nature Neuroscience, 16(3), 349-356. DOI: 10.1038/nn.3315 pdf

Zhang H & Ekstrom AD. (2013). Human Neural Systems Underlying Rigid and Flexible Forms of Allocentric Spatial Representation. Human Brain Mapping, 34(5), 1070-1087. DOI: 10.1002/hbm.21494 pdf

2012

Kern KC, Ekstrom AD, Suthana NA, Giesse BS, Montag M, Arshanapalli A, Bookheimer SY, & Sicotte NL. (2012). Fornix damage limits verbal memory functional compensation in multiple sclerosis. Neuroimage, 59(3), 2932-40. DOI: 10.1016/j.neuroimage.2011.09.071 pdf

Libby LA, Ekstrom AD, Ragland JD, & Ranganath C. (2012). Differential connectivity of perirhinal and parahippocampal cortices within human hippocampal subregions revealed by high-resolution functional imaging. Journal of Neuroscience, 32(19), 6550-6560. DOI: 10.1523/JNEUROSCI.3711-11.2012 pdf

Staba RJ, Ekstrom AD, Suthana NA, Burggren A, Fried I, Engel J Jr, & Bookheimer SY. (2012). Gray matter loss correlates with mesial temporal lobe neuronal hyper-excitability inside the human seizure-onset zone. Epilepsia, 53(1), 25-34. DOI: 10.1111/j.1528-1167.2011.03333.x pdf

Zhang H, Copara M, & Ekstrom AD. (2012). Differential Recruitment of Brain Networks Following Route and Cartographic Map Learning of Spatial Environments. PLoS ONE. 7(9), e44886. DOI: 10.1371/journal.pone.0044886 pdf

2011

Addante RJ, Watrous AJ, Yonelinas AP, Ekstrom AD, & Ranganath C. (2011). Prestimulus theta activity predicts correct source memory retrieval. Proceedings of the National Academy of Sciences, 108(26), 10702-10707. DOI: 10.1073/pnas.1014528108 pdf

Ekstrom AD, Copara MS, Isham EA, Wang W, & Yonelinas AP. (2011). Dissociable networks involved in spatial and temporal order source retrieval. Neuroimage, 56, 1803-1813. DOI: 10.1016/j.neuroimage.2011.02.033 pdf

Suthana N, Ekstrom AD, Moshirvaziri S, Knowlton B, & Bookheimer S. (2011). Dissociations within human hippocampal subregions during encoding and retrieval of spatial information. Hippocampus, 21(7), 694-701. DOI: 10.1002/hipo.20833 pdf

Watrous A, Fried I, & Ekstrom AD. (2011). Behavioral correlates of human hippocampal delta and theta oscillations during navigation. Journal of Neurophysiology, 105, 1747-1755. DOI: 10.1152/jn.00921.2010 pdf

2010

Donix M, Burggren AC, Suthana NA, Siddarth P, Ekstrom AD, Krupa AK, Jones M, Martin-Harris L, Ercoli LM, Miller KJ, Small GW, & Bookheimer SY. (2010). Family history of Alzheimer’s disease and hippocampal structure in healthy people. The American Journal of Psychiatry, 167(11), 1399-1406. DOI: 10.1176/appi.ajp.2010.09111575 pdf

Donix M, Burggren AC, Suthana NA, Siddarth P, Ekstrom AD, Krupa AK, Jones M, Rao A, Martin-Harris L, Ercoli LM, Miller KJ, Small GW, & Bookheimer SY. (2010). Longitudinal changes in medial temporal cortical thickness in normal subjects with the APOE-4 polymorphism. Neuroimage, 53(1), 37-43. DOI: 10.1016/j.neuroimage.2010.06.009 pdf

Ekstrom, AD. (2010). How and when the fMRI BOLD signal relates to underlying neural activity: The danger in dissociation. Brain Research Reviews, 62(2), 233-244. DOI: 10.1016/j.brainresrev.2009.12.004 pdf

Ekstrom AD. (2010). Navigation in Virtual Space: Psychological and Neural Aspects. In Encyclopedia of Behavioral Neuroscience (eds. Koob, Thompson and Le Moal). pdf

Jacobs J, Kahana MJ, Ekstrom AD, Mollison MV, & Fried I. (2010). A sense of direction in human entorhinal cortex. Proceedings of the National Academy of Sciences of the United States of America, 107(14), 6487-6492. DOI: 10.1073/pnas.0911213107 pdf

Jacobs J, Korolev IO, Caplan JB, Ekstrom AD, Litt B, Baltuch G, Fried I, Schulze-Bonhage A, Madsen JR, & Kahana MJ. (2010). Right-lateralized brain oscillations in human spatial navigation. Journal of Cognitive Neuroscience, 22(5), 824-836. DOI: 10.1162/jocn.2009.21240 pdf

Mukamel R, Ekstrom AD, Kaplan J, Iacoboni M, & Fried I. (2010). Single-neuron responses in humans during execution and observation of actions. Current Biology, 20(8), 750-756. DOI: 10.1016/j.cub.2010.02.045 pdf

Suthana NA, Krupa A, Donix M, Burggren A, Ekstrom AD, Jones M, Ercoli LM, Miller KJ, Siddarth P, Small GW, & Bookheimer SY. (2010). Reduced hippocampal CA2, CA3 and dentate gyrus activity in asymptotic people at genetic risk for Alzheimer’s disease. Neuroimage, 53(3), 1077-1084. DOI: 10.1016/j.neuroimage.2009.12.014 pdf

2009

Ekstrom AD, Bazih AJ, Suthana NA, Al-Hakim R, Ogura K, Zeineh M, Burggren AC, & Bookheimer SY. (2009). Advances in high-resolution imaging and computational unfolding of the human hippocampus. Neuroimage, 47(1), 42-49. DOI: 10.1016/j.neuroimage.2009.03.017 pdf

Ekstrom A, Suthana N, Millet D, Fried I, & Bookheimer S. (2009). Correlation between BOLD fMRI and theta-band local field potentials in the human hippocampal area. Journal of Neurophysiology, 101(5), 2668-2678. DOI: 10.1152/jn.91252.2008 pdf

Suthana NA, Ekstrom AD, Moshirvaziri S, Knowlton B, & Bookheimer SY. (2009). Human hippocampal CA1 involvement during allocentric encoding of spatial information. Journal of Neuroscience, 29(34), 10512-10519. DOI: 10.1523/JNEUROSCI.0621-09.2009 pdf

2008

Burggren AC, Zeineh MM, Ekstrom AD, Braskie MN, Thompson PM, Small GW, & Bookheimer SY. (2008). Reduced cortical thickness in hippocampal subregions among cognitively normal Apolipoprotein E e4 carriers. Neuroimage, 41(4), 1177-83. DOI: 10.1016/j.neuroimage.2008.03.039 pdf

Ekstrom A, Suthana N, Behnke E, Salamon N, Bookheimer S, & Fried I. (2008). High-resolution depth electrode localization and imaging in patients with pharmacologically intractable epilepsy. Technical note. Journal of Neurosurgery, 108(4), 812-815. DOI: 10.3171/JNS/2008/108/4/0812 pdf

2007

Ekstrom AD and Bookheimer SY. (2007). Spatial and temporal episodic memory retrieval recruit dissociable functional networks in the human brain. Learning and Memory, 14(10), 645-654. DOI: 10.1101/lm.575107 pdf

Ekstrom A, Viskontas I, Kahana MJ, Jacobs J, Upchurch K, Bookheimer SY, & Fried I. (2007). Contrasting roles of neural firing rate and local field potentials in human memory. Hippocampus, 17(8), 606-617. DOI: 10.1002/hipo.20300 pdf

Jacobs J, Kahana MJ, Ekstrom AD, & Fried I. (2007). Brain oscillations control timing of single-neuron activity in humans. Journal of Neuroscience, 27(14), 3839–3844. DOI: 10.1523/JNEUROSCI.4636-06.2007 pdf

Viskontas I, Ekstrom AD, Wilson CL, & Fried I. (2007). Characterizing interneuron and pyramidal cells in the human medial temporal lobe in vivo using extracellular recordings. Hippocampus, 17(1), 49-57. DOI: 10.1002/hipo.20241 pdf

2005

Ekstrom AD, Caplan JB, Shattuck K, Fried I, & Kahana MJ. (2005). Human hippocampal theta activity during virtual navigation. Hippocampus, 15(7), 881-889. DOI: 10.1002/hipo.20109 pdf

2003

Ekstrom AD, Kahana MJ, Caplan JB, Fields TA, Isham EA, Newman E, & Fried I. (2003). Cellular networks underlying human spatial navigation. Nature, 425(6954), 184-188. DOI: 10.1038/nature01964 pdf

2001

Redish AD, Battaglia FP, Chawla MK, Ekstrom AD, Gerrard JL, Lipa P, Rosenzweig ES, Worley PF, Guzowski JF, McNaughton BL, & Barnes CA. (2001). Independence of firing correlates of anatomically proximate hippocampal pyramidal cells. Journal of Neuroscience, 21(5), 1-6. pdf

Ekstrom AD, Meltzer J, McNaughton BL, & Barnes CA. (2001). NMDA receptor antagonism blocks Experience-Dependent Expansion of Hippocampal Place Fields. Neuron, 31, 631-638. pdf