We tested whether similarity between events triggers adaptive biases in how those events are remembered. We generated pairs of competing objects that were identical except in color and varied the degree of color similarity for the competing objects. Subjects (N = 123 across four experiments) repeatedly studied and were tested on associations between each of these objects and corresponding faces. As expected, high color similarity between competing objects created memory interference for object–face associations. Strikingly, high color similarity also resulted in a systematic bias in how the objects themselves were remembered: Competing objects with highly similar colors were remembered as being further apart (in color space) than they actually were. This repulsion of color memories increased with learning and served a clear adaptive purpose: Greater repulsion was associated with lower associative-memory interference. These findings reveal that similarity between events triggers adaptive-memory distortions that minimize interference.
AlyM.RanganathC.YonelinasA. P. (2013). Detecting changes in scenes: The hippocampus is critical for strength-based perception. Neuron, 78, 1127–1137. https://doi.org/10.1016/j.neuron.2013.04.018
2.
AlyM.Turk-BrowneN. B. (2018). Flexible weighting of diverse inputs makes hippocampal function malleable. Neuroscience Letters, 680, 13–22. https://doi.org/10.1016/j.neulet.2017.05.063
3.
AndersonM. C. (2003). Rethinking interference theory: Executive control and the mechanisms of forgetting. Journal of Memory and Language, 49, 415–445. https://doi.org/10.1016/j.jml.2003.08.006
4.
AndersonM. C.BjorkR. A.BjorkE. L. (1994). Remembering can cause forgetting: Retrieval dynamics in long-term memory. Journal of Experimental Psychology: Learning, Memory, and Cognition, 20, 1063–1087. https://doi.org/10.1037/0278-7393.20.5.1063
5.
BaeG.-Y.LuckS. J. (2017). Interactions between visual working memory representations. Attention, Perception, & Psychophysics, 79, 2376–2395. https://doi.org/10.3758/s13414-017-1404-8
6.
BakkerA.KirwanC. B.MillerM.StarkC. E. L. (2008). Pattern separation in the human hippocampal CA3 and dentate gyrus. Science, 319, 1640–1642. https://doi.org/10.1126/science.1152882
BarnesJ. M.UnderwoodB. J. (1959). “Fate” of first-list associations in transfer theory. Journal of Experimental Psychology, 58, 97–105. https://doi.org/10.1037/h0047507
9.
BradyT. F.KonkleT.AlvarezG. A.OlivaA. (2013). Real-world objects are not represented as bound units: Independent forgetting of different object details from visual memory. Journal of Experimental Psychology: General, 142, 791–808. https://doi.org/10.1037/a0029649
10.
ChanalesA. J. H.OzaA.FavilaS. E.KuhlB. A. (2017). Overlap among spatial memories triggers repulsion of hippocampal representations. Current Biology, 27, 2307–2317.e5. https://doi.org/10.1016/j.cub.2017.06.057
11.
ColginL. L.MoserE. I.MoserM.-B. (2008). Understanding memory through hippocampal remapping. Trends in Neurosciences, 31, 469–477. https://doi.org/10.1016/j.tins.2008.06.008
12.
DetreG. J.NatarajanA.GershmanS. J.NormanK. A. (2013). Moderate levels of activation lead to forgetting in the think/no-think paradigm. Neuropsychologia, 51, 2371–2388. https://doi.org/10.1016/j.neuropsychologia.2013.02.017
13.
Dimsdale-ZuckerH. R.RitcheyM.EkstromA. D.YonelinasA. P.RanganathC. (2018). CA1 and CA3 differentially support spontaneous retrieval of episodic contexts within human hippocampal subfields. Nature Communications, 9, Article 294. https://doi.org/10.1038/s41467-017-02752-1
14.
EzzyatY.DavachiL. (2014). Similarity breeds proximity: Pattern similarity within and across contexts is related to later mnemonic judgments of temporal proximity. Neuron, 81, 1179–1189. https://doi.org/10.1016/j.neuron.2014.01.042
15.
FavilaS. E.ChanalesA. J. H.KuhlB. A. (2016). Experience-dependent hippocampal pattern differentiation prevents interference during subsequent learning. Nature Communications, 7, Article 11066. https://doi.org/10.1038/ncomms11066
16.
FörsterJ.LibermanN.KuschelS. (2008). The effect of global versus local processing styles on assimilation versus contrast in social judgment. Journal of Personality and Social Psychology, 94, 579–599. https://doi.org/10.1037/0022-3514.94.4.579
17.
GluckM. A.MyersC. E. (1993). Hippocampal mediation of stimulus representation: A computational theory. Hippocampus, 3, 491–516. https://doi.org/10.1002/hipo.450030410
18.
HulbertJ. C.NormanK. A. (2015). Neural differentiation tracks improved recall of competing memories following interleaved study and retrieval practice. Cerebral Cortex, 25, 3994–4008. https://doi.org/10.1093/cercor/bhu284
19.
KimG.NormanK. A.Turk-BrowneN. B. (2017). Neural differentiation of incorrectly predicted memories. The Journal of Neuroscience, 37, 2022–2031. https://doi.org/10.1523/JNEUROSCI.3272-16.2017
20.
KruegerJ.RothbartM. (1990). Contrast and accentuation effects in category learning. Journal of Personality and Social Psychology, 59, 651–663. https://doi.org/10.1037/0022-3514.59.4.651
Lewis-PeacockJ. A.NormanK. A. (2014). Competition between items in working memory leads to forgetting. Nature Communications, 5, Article 5768. https://doi.org/10.1038/ncomms6768
NewmanE. L.NormanK. A. (2010). Moderate excitation leads to weakening of perceptual representations. Cerebral Cortex, 20, 2760–2770. https://doi.org/10.1093/cercor/bhq021
25.
NormanK. A.NewmanE. L.DetreG. (2007). A neural network model of retrieval-induced forgetting. Psychological Review, 114, 887–953. https://doi.org/10.1037/0033-295X.114.4.887
26.
NormanK. A.NewmanE. L.DetreG.PolynS. (2006). How inhibitory oscillations can train neural networks and punish competitors. Neural Computation, 18, 1577–1610. https://doi.org/10.1162/neco.2006.18.7.1577
27.
O’ReillyR. C. (2004). The division of labor between the neocortex and hippocampus. In HoughtonG. (Ed.), Connectionist models in cognitive psychology (pp. 143–174). Psychology Press.
28.
OsgoodC. E. (1949). The similarity paradox in human learning: A resolution. Psychological Review, 56(3), 132–143. https://doi.org/10.1037/h0057488
29.
RademakerR. L.BloemI. M.De WeerdP.SackA. T. (2015). The impact of interference on short-term memory for visual orientation. Journal of Experimental Psychology: Human Perception and Performance, 41, 1650–1665. https://doi.org/10.1037/xhp0000110
30.
RichardsB. A.XiaF.SantoroA.HusseJ.WoodinM. A.JosselynS. A.FranklandP. W. (2014). Patterns across multiple memories are identified over time. Nature Neuroscience, 17, 981–986. https://doi.org/10.1038/nn.3736
31.
RichterF. R.ChanalesA. J. H.KuhlB. A. (2016). Predicting the integration of overlapping memories by decoding mnemonic processing states during learning. NeuroImage, 124, 323–335. https://doi.org/10.1016/j.neuroimage.2015.08.051
32.
RitvoV. J. H.Turk-BrowneN. B.NormanK. A. (2019). Nonmonotonic plasticity: How memory retrieval drives learning. Trends in Cognitive Sciences, 23, 726–742. https://doi.org/10.1016/j.tics.2019.06.007
33.
SchacterD. L. (1999). The seven sins of memory: Insights from psychology and cognitive neuroscience. American Psychologist, 54, 182–203. https://doi.org/10.1037/0003-066X.54.3.182
34.
SchapiroA. C.KustnerL. V.Turk-BrowneN. B. (2012). Shaping of object representations in the human medial temporal lobe based on temporal regularities. Current Biology, 22, 1622–1627. https://doi.org/10.1016/j.cub.2012.06.056
35.
SchlichtingM. L.MumfordJ. A.PrestonA. R. (2015). Learning-related representational changes reveal dissociable integration and separation signatures in the hippocampus and prefrontal cortex. Nature Communications, 6, Article 8151. https://doi.org/10.1038/ncomms9151
36.
ShohamyD.WagnerA. D. (2008). Integrating memories in the human brain: Hippocampal-midbrain encoding of overlapping events. Neuron, 60, 378–389. https://doi.org/10.1016/j.neuron.2008.09.023
37.
StormB. C.BjorkE. L.BjorkR. A. (2008). Accelerated relearning after retrieval-induced forgetting: The benefit of being forgotten. Journal of Experimental Psychology: Learning, Memory, and Cognition, 34, 230–236. https://doi.org/10.1037/0278-7393.34.1.230
ZeithamovaD.DominickA. L.PrestonA. R. (2012). Hippocampal and ventral medial prefrontal activation during retrieval-mediated learning supports novel inference. Neuron, 75, 168–179. https://doi.org/10.1016/j.neuron.2012.05.010
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
