Capturing the Past
A mother and daughter swirl steaming coffee, reminiscing about their Ocean City vacation ten years ago. The mother pictures her daughter gleefully building sandcastles, eating sandwiches by the shore and begging not to leave at the end of the trip. The daughter stares at her mother in disbelief, recalling a completely different version of the story. She remembers getting sunburned to the point of peeling, slicing her foot on a sharp shell and being chased by an aggressive seagull who wanted her chips. What causes two people to remember the happiness of past experiences differently over time? It is possible that the mother initially misinterpreted her child as being happy, when she was not - but new research indicates there may also be other factors at play.
Current Life Satisfaction & Past Perspectives
One reason happiness can appear elusive is that memories of past well-being can be influenced by one’s current feelings.[1] In the classic test to determine whether someone is an optimist or a pessimist, a person evaluates a glass of liquid and is asked to state whether the glass is half-empty or half-full. In terms of recalling happiness, it may be helpful to reconsider this question from a different perspective: “Is the glass filling up or is it draining?” A person’s assessment of past well-being may tie into the perception of their overall life trajectory by placing the past in context of current levels of life-satisfaction and projected expectations of future happiness.[2]
Is the glass filling up or is it draining?
Whether a person is an optimist or a pessimist may have an impact on their perception of past events. To analyze the relationship between past perceptions of happiness and current mood, Prati & Senik (2022) evaluated data from four surveys (three publicly available national surveys and one commercial survey) including 260,000 surveys from more than 60,000 individuals in Germany, Britain, France, and the United States.[3] The results showed that happy people tended to remember their lives as progressively becoming better while those who were unhappy tended to view their happiness as deteriorating.[4]
One potential explanation for these findings is that a person’s experience of current happiness may inherently be dependent on feeling better than yesterday.[5] A person who is happy in their present life may therefore need to remember their past as slightly less happy to feel that they are making progress, while a person who is unhappy now may view the past as happier in order to justify current feelings.[6] These misconceptions may cyclically alter an individual’s future behavior leading happy people (who perceive their situation as continually improving) more open to new experiences, while unhappy people (who perceive their situation to be getting worse) to perceive a higher risk associated with change and taking chances.[7]
Those who struggle with severe depression may also experience additional skews in memory. Comparing 30 individuals with major depressive disorder (MDD) to 46 healthy individuals in a control group, Kim & Yoon (2020) found that those with MDD experienced more sadness when recalling their saddest memories and less happiness associated with their happiest memories, which may lead to hindering mood regulation and perpetuate a negative cycle.[8]
What Makes a Memory Happy or Sad?
Neuroscientists recently discovered that one specific molecule determines whether an event is stored as a good or bad memory.[9] As the brain assesses an experience to be categorized as positive or negative, neurons adjust the release of neurotensin (a small peptide molecule) which sends the information through different neural pathways.[10] Hao Li, postdoctoral researcher at the Salk Institute for Biological Studies in California, explained to Quanta Magazine that conditions such as anxiety or addiction may be the result of breakdowns in this process that result in “too much negative processing.”[11] From an evolutionary perspective, this process assisted in avoiding things that produced negative memories (e.g., a dangerous animal dwelling in a certain area or a food that made a person sick).[12] This process still helps people today to assess whether a situation is safe or dangerous by associating items with happy or sad memories.
Storing Memories of Emotions
While the above explanation accounts for generally categorizing a memory as positive or negative, there is a simultaneous belief that the intensity of emotions can’t be stored in the form of memories. To illustrate this concept, Wilson et al. (2003) gave the example that people cannot go on vacation just one time and continually live that happiness through memories; they need to repeatedly go on vacation to enjoy the experience once again.[13] Memories of emotions fade over time and people later rely on additional information to reconstruct their feelings which may erroneously lead to incorporating experiences and knowledge gained after the initial event.[14] This idea is further reinforced by research conducted by Kaplan et al. (2016) which interviewed participants to determine how they felt about election results both immediately after the election and one-month later following the 2008 and 2012 presidential elections.[15] Their analysis showed that the intensity of emotion diminished over time, which corresponds with a diminishing appraisal of the importance of the election as time passed.[16]
However, the inaccurate report of memories does not always present in the form of diminished feelings. Wilson et al. (2003) describes one type of change in memory due to emotions as “retrospective impact bias,” which leads people to overestimate their reactions to past events which can then potentially impact their ability to accurately recall information (e.g., the emotional impact that a fan will experience if their favorite sports team wins).[17] The incorrect recollection of memories is supported by an analysis of data collected from 1997-2009 through the British Household Panel Survey (BHPS) which found that 90% of participants incorrectly recalled their own self-reported levels of past happiness at least one time.[18] Similarly, a study conducted by Safer, Levine and Drapalski (2002) found that the recollection students had of how anxious they were before taking an exam was influenced by the grade they later received on the exam.[19]
Memory Engrams
Accurate recollection of memories involves multiple parts of the brain and may be affected by a variety of factors. A memory engram refers to the enduring changes (chemical or physical) that take place in brain networks when new information is learned representing acquired memory information.[20] Research conducted by Roy et al. (2022) supports the unified engram complex hypothesis for memory storage which proposes that each specific memory is stored in cell ensembles that are functionally connected and distributed widely across multiple brain regions.[21] Reactivating these neurons is believed to give rise to the recall of a specific memory.[22] However, the requirement of activating neurons in multiple regions of the brain may can potentially lead to the development of false memories.[23]
Selective Memories
Dating back to 1976, research conducted by Mischel, Ebbesen and Zeiss found that individuals exposed to both positive and negative descriptions of their personalities were more likely to remember the positive information.[24] Using this idea as a catalyst, Chew & Zhao (2020) evaluated three types of positive memory errors:[25]
Positive delusion - fabricating the memory of a positive event that did not happen
Positive amnesia - forgetting a negative event
Positive confabulation - distorting the memory of a past negative event into a positive event
Their research (which included 701 participants in Singapore and 669 from Beijing participating in both phases of the trial) found that individuals who answered questions regarding their performance on an IQ test (both immediately following the test and several months later) found considerable incidence of positive delusion (64.12%), amnesia (33.95%) and confabulation (10.63%).[26] These results show participants were more likely to forget their inaccuracies and exhibit positive false memories than negative false memories.[27]
Perceptions of Happiness Throughout One’s Lifespan
Age is also believed to be a factor in skewing a person’s view of past happiness. Hyman (2014) analyzed qualitative interviews of 26 adults from different regions of the United Kingdom and found that older adults (aged 60 and above) were more likely to view the past as happier, both in their personal lives as well as in society as a whole.[28] It was also found that happiness in the present could be gained by reminiscing about the past.[29]
Lachman et al. (2008) examined the responses of 3,793 participants, aged 24 to 74 at baseline, who provided retrospective, prospective and present ratings on two different occasions 8-10 years apart.[30] Their results showed that individuals over 65 found the past and present to be equally satisfying, though there was some belief that the future may not be equally so. Conversely, younger individuals felt their lives in the present were more satisfying than they were in the past.[31] These findings support the life-span motivational interpretation of recalling memories, reiterating that the stage of a person’s life may impact recollections of happiness.[32] In other words, those who are older are more likely to see their future as declining while those who are younger tend to see their future as improving. Since perceptions of the past may inherently be dependent on an individual’s perceived current and future perceptions of happiness, those who are younger may be more likely to minimize past happiness in hopes of a brighter future to look forward to while older individuals may remember the past fondly if they expect a diminished amount of happiness in the future.
How Memories Change
People not only have a tendency to change perceptions of past happiness, but sometimes memories can be entirely fabricated. Hugo Munstenberg first started studying the psychology of false memories in 1906 when a farmer’s son confessed to murdering a woman whose body was found in Chicago - despite having a valid alibi. Each retelling of the story added more details that were sometimes contradictory.[33] This raised the question of suggestibility and whether police officers may have been influencing a confession, though it would be decades before the topic was studied in further detail.[34]
In addition to outside influence skewing a person’s memories, sometimes the brain’s recollection process can be the culprit. Northwestern University’s Feinberg School of Medicine (2012) conducted research showing that every time a person recalls a memory the brain network changes in a way that can alter how the event is later recalled.[35] The memory can potentially become less precise every time it is remembered, eventually becoming a completely false memory.[36] Each person out of the 70 studied showed this effect.[37]
This year, new research also emerged revealing false memories may generate more quickly than previously believed. Experiments funded by the European Research Council (2023) showed the creation of false memories can occur within seconds.[38] The 534 participants were shown an initial set of letters from the western alphabet on a slide (in either mirrored or original orientation) with some participants shown a second slide intended to scramble the original memory.[39] When asked to recall a target letter from the first slide, within 500 milliseconds, 20% of participants formed an illusory memory of the target letter with the number increasing to 30% after 3 seconds.[40] Researchers believe this was the result of human brains altering occurrences based on what it expects to see, which can be difficult to process when there is an unexpected change, such as seeing a letter backwards.[41]
Benefits of Nostalgia
Nostalgic memories are also believed to positively skew our perceptions of the past. People sometimes feel nostalgic over things they did not like at the time such as a song they once found annoying or difficult class.[42] These memories may be induced by merely smelling a specific scent or sound (e.g., the smell of summer grass producing memories of playing outside as a child),[43] but the question can be raised as to whether reliving the past is psychologically healthy. FioRito and Routledge (2020) proposed that nostalgia is actually a future-oriented emotional experience instead of a retrospective event because it involves reflection on past behavior and experiences in order to prepare for future decisions.[44] Nostalgia is viewed by experts as a defense response that can alleviate sadness, strengthen social bonds, improve mood and increase spirituality.[45] It has been described as a redemptive sequence in which the feelings of loss and longing lead to the positive feelings of hope, happiness and gratitude.[46] By increasing a sense of meaning, nostalgia may help motivate individuals to pursue important life goals.[47]
While the subjectivity of past happiness may be impacted by a variety of factors, it can be helpful to take a deep breath and put memories into perspective. Though evidence indicates that memories are impacted by our current emotional state,[48] modern psychology teaches us that these changes are not inherently negative and that some changes to memories can be beneficial for helping individuals process the past and make more informed choices.[49] Speaking with others about shared events or keeping a journal about current experiences are ways to assess the accuracy of past memories.
However, if a person feels confused about the past and is having trouble sorting out truth from fiction or is having difficulty processing distressing memories from their past, it may be helpful to speak with a licensed mental health professional.
Contributed by: Theresa Nair
Editor: Jennifer (Ghahari) Smith, Ph.D.
REFERENCES
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2 Lachman ME, Röcke C, Rosnick C, Ryff CD. Realism and illusion in americans' temporal views of their life satisfaction: Age differences in reconstructing the past and anticipating the future. Psychol Sci. 2008;19(9):889-897. doi: 10.1111/j.1467-9280.2008.02173.x.
3 Prati A, Senik C. Feeling good is feeling better. Psychol Sci. 2022;33(11):1828-1841. doi: 10.1177/09567976221096158.
4 APS (2022)
5 Ibid.
6 Prati & Senik (2022)
7 Ibid.
8 Kim D, Yoon KL. Emotional response to autobiographical memories in depression: Less happiness to positive and more sadness to negative memories. Cogn Behav Ther. 2020;ahead-of-print(-):1-11. doi: 10.1080/16506073.2020.1765859.
9 Li H, Namburi P, Olson JM, et al. Neurotensin orchestrates valence assignment in the amygdala. Nature. 2022;608(7923):586-592. https://doi.org/10.1038/s41586-022-04964-y. doi: 10.1038/s41586-022-04964-y.
10 Ibid.
11 Saplakoglu Y. A good memory or a bad one? one brain molecule decides. Quanta Magazine Web site. https://www.quantamagazine.org/a-good-memory-or-a-bad-one-one-brain-molecule-decides-20220907/. Updated 2022. Accessed May 4, 2023.
12 Ibid.
13 Wilson TD, Meyers J, Gilbert DT. "How happy was I, anyway?" A retrospective impact bias. SOC COGNITION. 2003;21(6):421-446. doi: 10.1521/soco.21.6.421.28688.
14 Ibid.
15 Kaplan, R. L., Levine, L. J., Lench, H. C., & Safer, M. A. Forgetting feelings: Opposite biases in reports of the intensity of past emotion and mood. Emotion. 2016;16(3):309–319. doi: 10.1037/emo0000127
16 Ibid.
17 Wilson et al. (2003)
18 Prati & Senik (2022)
19 Wilson et al. (2003)
20 Josselyn SA, Tonegawa S. Memory engrams: Recalling the past and imagining the future. Science. 2020;367(6473):eaaw4325. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7577560/. Accessed May 22, 2023. doi: 10.1126/science.aaw4325.
21 Roy DS, Park Y, Kim ME, et al. Brain-wide mapping reveals that engrams for a single memory are distributed across multiple brain regions. Nature Communications. 2022;13(1):1799. https://doi.org/10.1038/s41467-022-29384-4. doi: 10.1038/s41467-022-29384-4.
22 Josselyn & Tonegawa (2020)
23 Ortega-de San Luis C, Ryan TJ. Understanding the physical basis of memory: Molecular mechanisms of the engram. J Biol Chem. 2022;298(5):101866. doi: 10.1016/j.jbc.2022.101866.
24 Mischel, W., Ebbesen, E. B., & Zeiss, A. M. (1976). Determinants of selective memory about the self. Journal of Consulting and Clinical Psychology. 1976; 44(1), 92–103. Doi: 10.1037/0022-006X.44.1.92
25 Chew SH, Huang W, Zhao X. Motivated false memory. The Journal of political economy. 2020;128(10):3913-3939. doi: 10.1086/709971.
26 Ibid.
27 Ibid.
28 Hyman L. Happiness and memory: Some sociological reflections. SOCIOL RES ONLINE. 2014;19(2):1-9. doi: 10.5153/sro.3268.
29 Ibid.
30 Lachman et al. (2008)
31 Ibid.
32 Ibid.
33 Starr D. Remembering a crime that you didn’t commit. The New Yorker Web site. https://www.newyorker.com/tech/annals-of-technology/false-memory-crime. Updated 2015. Accessed May 12, 2023.
34 Dodgson L. Our brains sometimes create 'false memories' — but science suggests we could be better off this way. Business Insider Web site. https://www.businessinsider.com/science-of-false-memories-2017-12. Updated 2017. Accessed May 7, 2023.
35 M. Your memory is like the telephone game. Northwestern Now Web site. https://news.northwestern.edu/stories/2012/09/your-memory-is-like-the-telephone-game. Updated 2012. Accessed May 5, 2023.
36 Ibid.
37 Ibid.
38 . Otten M, Seth AK, Pinto Y. Seeing Ɔ, remembering C: Illusions in short-term memory. PLOS ONE. 2023;18(4):e0283257. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0283257. Accessed May 22, 2023. doi: 10.1371/journal.pone.0283257.
39 Nelson F. Your brain can create a false memory quicker than you think. ScienceAlert Web site. https://www.sciencealert.com/your-brain-can-create-a-false-memory-quicker-than-you-think. Updated 2023. Accessed May 4, 2023.
40 Otten et al. (2023)
41 Nelson (2023)
42 Brooks AC. Nostalgia is a shield against unhappiness. The Atlantic Web site. https://www.theatlantic.com/family/archive/2023/03/nostalgia-defense-unhappiness-happy-memories/673320/. Updated 2023. Accessed May 3, 2023.
43 Ibid.
44 FioRito TA, Routledge C. Is nostalgia a past or future-oriented experience? affective, behavioral, social cognitive, and neuroscientific evidence. Frontiers in psychology. 2020;11:1133. https://search.proquest.com/docview/2424436969. doi: 10.3389/fpsyg.2020.01133.
45 Brooks (2023)
46 Routledge C. The surprising power of nostalgia at work. Harvard Business Review. 2021. https://hbr.org/2021/04/the-surprising-power-of-nostalgia-at-work. Accessed May 3, 2023.
47 Ibid.
48 APS (2022)
49 Dodgson L. Our brains sometimes create 'false memories' — but science suggests we could be better off this way. Business Insider Web site. https://www.businessinsider.com/science-of-false-memories-2017-12. Updated 2017. Accessed May 22, 2023.