title: The hippocampus, time, and memory across scales.
abstract: A wealth of experimental studies with animals have offered insights about how neural networks within the hippocampus support the temporal organization of memories. These studies have revealed the existence of "time cells" that encode moments in time, much as the well-known "place cells" map locations in space. Another line of work inspired by human behavioral studies suggests that episodic memories are mediated by a state of temporal context that changes gradually over long time scales, up to at least a few thousand seconds. In this view, the "mental time travel" hypothesized to support the experience of episodic memory corresponds to a "jump back in time" in which a previous state of temporal context is recovered. We suggest that these 2 sets of findings could be different facets of a representation of temporal history that maintains a record at the last few thousand seconds of experience. The ability to represent long time scales comes at the cost of discarding precise information about when a stimulus was experienced--this uncertainty becomes greater for events further in the past. We review recent computational work that describes a mechanism that could construct such a scale-invariant representation. Taken as a whole, this suggests the hippocampus plays its role in multiple aspects of cognition by representing events embedded in a general spatiotemporal context. The representation of internal time can be useful across nonhippocampal memory systems.
authors.affiliation: Center for Memory and Brain, Boston University.
authors.forename: Marc W
authors.initials: MW
authors.lastname: Howard
authors.forename: Howard
authors.initials: H
authors.lastname: Eichenbaum
mesh_terms: D000818:Animals; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D008568:Memory / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D013998:Time Perception / Q000502:physiology*
references.citation: Psychol Rev. 2005 Jan;112(1):3-42
references.pmid: 15631586
references.citation: J Neurosci. 2013 Mar 20;33(12):5422-32
references.pmid: 23516307
references.citation: Cogn Neuropsychol. 2001 Mar 1;18(2):97-123
references.pmid: 20945208
references.citation: Cogn Sci. 2010;34(1):10-50
references.pmid: 20396653
references.citation: Hippocampus. 1996;6(6):579-90
references.pmid: 9034847
references.citation: Psychol Rev. 1965 Mar;72:89-104
references.pmid: 14282677
references.citation: Proc Natl Acad Sci U S A. 2012 Nov 20;109(47):19462-7
references.pmid: 23132944
references.citation: Psychol Rev. 2001 Apr;108(2):452-78
references.pmid: 11381837
references.citation: Psychol Sci. 2005 Nov;16(11):898-904
references.pmid: 16262777
references.citation: J Exp Psychol Anim Behav Process. 1989 Jan;15(1):23-35
references.pmid: 2926333
references.citation: Hippocampus. 2009 Sep;19(9):790-9
references.pmid: 19219919
references.citation: Psychol Rev. 2008 Apr;115(2):426-46
references.pmid: 18426296
references.citation: Neurocase. 2001;7(5):357-82
references.pmid: 11744778
references.citation: J Exp Psychol Learn Mem Cogn. 2013 Jan;39(1):297-303
references.pmid: 22582969
references.citation: Science. 2008 Sep 5;321(5894):1322-7
references.pmid: 18772431
references.citation: Proc Natl Acad Sci U S A. 2013 Feb 19;110(8):3119-24
references.pmid: 23382181
references.citation: Psychol Rev. 1995 Jul;102(3):419-457
references.pmid: 7624455
references.citation: Nature. 2004 Sep 9;431(7005):188-91
references.pmid: 15356631
references.citation: Neuron. 2013 Mar 20;77(6):1002-16
references.pmid: 23522038
references.citation: J Cogn Neurosci. 1996 Summer;8(3):257-77
references.pmid: 23968151
references.citation: J Neurosci. 2006 Aug 23;26(34):8702-6
references.pmid: 16928858
references.citation: J Exp Psychol Learn Mem Cogn. 1999 May;25(3):563-82
references.pmid: 10368927
references.citation: Neuron. 2013 Jun 19;78(6):1090-101
references.pmid: 23707613
references.citation: Science. 1998 Apr 3;280(5360):77-81
references.pmid: 9525860
references.citation: Proc Natl Acad Sci U S A. 2003 Feb 18;100(4):2157-62
references.pmid: 12578977
references.citation: Psychol Rev. 2013 Jan;120(1):155-89
references.pmid: 23230891
references.citation: J Neurosci. 2002 Jul 1;22(13):5760-8
references.pmid: 12097529
references.citation: Hippocampus. 2013 Mar;23(3):193-201
references.pmid: 23197396
references.citation: Behav Brain Res. 2012 Apr 21;230(1):259-67
references.pmid: 22366272
references.citation: Behav Neurosci. 1986 Oct;100(5):729-44
references.pmid: 3778636
references.citation: Neuron. 2009 Feb 26;61(4):621-34
references.pmid: 19249281
references.citation: Brain Res Cogn Brain Res. 1992 Jun;1(1):3-38
references.pmid: 15497433
references.citation: J Neurosci. 2014 Mar 26;34(13):4692-707
references.pmid: 24672015
references.citation: Nat Neurosci. 2011 Mar;14(3):366-72
references.pmid: 21317906
references.citation: J Neurosci. 2013 Mar 27;33(13):5698-704
references.pmid: 23536083
references.citation: Science. 2012 Oct 12;338(6104):270-3
references.pmid: 23066083
references.citation: Nat Neurosci. 2004 Aug;7(8):887-93
references.pmid: 15235607
references.citation: J Exp Psychol Learn Mem Cogn. 2008 Jan;34(1):32-49
references.pmid: 18194053
references.citation: Proc Natl Acad Sci U S A. 2012 Sep 4;109(36):14357-62
references.pmid: 22908285
references.citation: J Neurosci. 2013 Mar 13;33(11):4854-66
references.pmid: 23486956
references.citation: Nat Neurosci. 2002 May;5(5):458-62
references.pmid: 11976705
references.citation: Behav Processes. 2007 Jun;75(2):188-98
references.pmid: 17446012
references.citation: J Neurosci. 2010 Nov 17;30(46):15558-65
references.pmid: 21084610
references.citation: Psychol Bull. 2007 Sep;133(5):800-32
references.pmid: 17723031
references.citation: J Neurosci. 2009 Mar 18;29(11):3475-84
references.pmid: 19295153
references.citation: Trends Cogn Sci. 2003 Jul;7(7):313-319
references.pmid: 12860190
references.citation: Behav Neurosci. 2002 Apr;116(2):286-90
references.pmid: 11996313
references.citation: J Neurosci. 2011 Sep 14;31(37):13157-67
references.pmid: 21917799
references.citation: J Neurosci. 2011 Feb 16;31(7):2706-11
references.pmid: 21325539
references.citation: Brain Res Cogn Brain Res. 2004 Oct;21(2):139-70
references.pmid: 15464348
references.citation: Psychol Rev. 2009 Jan;116(1):129-56
references.pmid: 19159151
references.citation: Nature. 1996 May 30;381(6581):425-8
references.pmid: 8632799
references.citation: Psychol Rev. 2000 Jan;107(1):127-81
references.pmid: 10687405
references.citation: J Neurosci. 2007 Mar 14;27(11):2948-57
references.pmid: 17360918
references.citation: Behav Neurosci. 2005 Jun;119(3):781-6
references.pmid: 15998199
references.citation: Hippocampus. 2012 Sep;22(9):1833-47
references.pmid: 22488671
references.citation: J Exp Psychol Learn Mem Cogn. 1999 Jul;25(4):923-41
references.pmid: 10439501
references.citation: Philos Trans R Soc Lond B Biol Sci. 1971 Jul 1;262(841):23-81
references.pmid: 4399412
references.citation: Neurobiol Learn Mem. 2001 Nov;76(3):447-61
references.pmid: 11726247
references.citation: Neuron. 2007 Nov 8;56(3):530-40
references.pmid: 17988635
references.citation: Psychol Rev. 2007 Jul;114(3):539-76
references.pmid: 17638496
references.citation: Hippocampus. 2007;17(9):697-708
references.pmid: 17607757
references.citation: Cereb Cortex. 2011 Feb;21(2):272-80
references.pmid: 20494967
references.citation: Psychon Bull Rev. 2008 Feb;15(1):58-63
references.pmid: 18605480
references.citation: J Neurosci. 2006 Sep 6;26(36):9162-72
references.pmid: 16957073
references.citation: Brain Res Cogn Brain Res. 1998 Jul;7(1):15-39
references.pmid: 9714713
references.citation: J Neurosci. 1982 Mar;2(3):361-75
references.pmid: 7062115
references.citation: Nat Rev Neurosci. 2009 Apr;10(4):272-82
references.pmid: 19300446
references.citation: Hippocampus. 2007;17(10):988-1002
references.pmid: 17554771
references.citation: Science. 1995 Mar 10;267(5203):1512-5
references.pmid: 7878473
references.citation: Neuron. 2000 Jul;27(1):169-78
references.pmid: 10939340
references.citation: J Exp Psychol Anim Behav Process. 2005 Jan;31(1):31-9
references.pmid: 15656725
references.citation: Psychol Rev. 2008 Oct;115(4):893-912
references.pmid: 18954208
references.citation: J Neurosci. 2010 May 26;30(21):7414-22
references.pmid: 20505108
references.citation: Brain Res. 1971 Nov;34(1):171-5
references.pmid: 5124915
references.citation: Behav Brain Res. 1997 Dec;89(1-2):1-34
references.pmid: 9475612
references.citation: PLoS Biol. 2006 Nov;4(12):e424
references.pmid: 17132050
references.citation: Cereb Cortex. 2007 Aug;17(8):1766-81
references.pmid: 17030561
references.citation: Neuron. 2006 Nov 9;52(3):547-56
references.pmid: 17088219
references.citation: Psychol Rev. 2003 Oct;110(4):611-46
references.pmid: 14599236
references.citation: Psychol Rev. 2007 Jan;114(1):152-76
references.pmid: 17227185
references.citation: J Neurosci. 2012 Feb 15;32(7):2473-84
references.pmid: 22396421
references.citation: Neuron. 2003 Dec 18;40(6):1227-39
references.pmid: 14687555
references.citation: Learn Mem. 1996 Sep-Oct;3(2-3):279-87
references.pmid: 10456097
references.citation: Curr Opin Neurobiol. 2006 Dec;16(6):701-9
references.pmid: 17084616
references.citation: Psychon Bull Rev. 2005 Oct;12(5):787-805
references.pmid: 16523998
references.citation: Trends Cogn Sci. 2011 Aug;15(8):340-1
references.pmid: 21763175
references.citation: J Exp Psychol Learn Mem Cogn. 2005 Nov;31(6):1213-20
references.pmid: 16393041
references.citation: Proc Natl Acad Sci U S A. 2012 Mar 27;109(13):5086-91
references.pmid: 22421138
references.citation: Mem Cognit. 1996 Jan;24(1):103-9
references.pmid: 8822162
references.citation: Neuron. 2000 Sep;27(3):623-33
references.pmid: 11055443
references.citation: J Comput Neurosci. 2005 Jan-Feb;18(1):41-53
references.pmid: 15789168
references.citation: Neuropsychologia. 1990;28(8):803-13
references.pmid: 2247207
references.citation: Behav Brain Res. 1999 Sep;103(2):123-33
references.pmid: 10513581
references.citation: Science. 1993 Aug 20;261(5124):1055-8
references.pmid: 8351520
references.citation: Eur J Neurosci. 2012 Apr;35(7):1011-23
references.pmid: 22487032
references.citation: Neuropsychologia. 1991;29(9):849-59
references.pmid: 1944882
references.citation: Learn Mem. 2007 Sep 24;14(10):645-54
references.pmid: 17893237
references.citation: Psychol Rev. 2000 Apr;107(2):289-344
references.pmid: 10789198
references.citation: Trends Neurosci. 2009 Feb;32(2):73-8
references.pmid: 19136158
references.citation: Neuron. 2011 Aug 25;71(4):737-49
references.pmid: 21867888
references.citation: Hippocampus. 2011 Nov;21(11):1240-9
references.pmid: 20665593
references.citation: Neuron. 1996 Nov;17(5):813-22
references.pmid: 8938115
references.citation: Psychon Bull Rev. 2009 Oct;16(5):945-51
references.pmid: 19815803
references.citation: Science. 2011 Aug 5;333(6043):773-6
references.pmid: 21817056
references.citation: Neural Comput. 2012 Jan;24(1):134-93
references.pmid: 21919782
references.citation: Behav Neurosci. 2012 Apr;126(2):258-69
references.pmid: 22352787
references.citation: J Exp Psychol Gen. 2010 May;139(2):341-64
references.pmid: 20438255
references.citation: Nat Neurosci. 1998 Aug;1(4):310-7
references.pmid: 10195165
references.citation: Neuropsychologia. 1991;29(6):601-18
references.pmid: 1944864
references.citation: J Neurosci. 2011 Feb 23;31(8):2828-34
references.pmid: 21414904
references.citation: Annu Rev Neurosci. 2007;30:123-52
references.pmid: 17417939
references.citation: Ann Neurosci. 2010 Apr;17(2):87-91
references.pmid: 25205878
references.citation: J Neurosci. 2011 Mar 2;31(9):3169-75
references.pmid: 21368028