The scientific nature of false and repressed memories

The issue of how traumatic experiences are remembered is one of the most contested areas in psychology. An especially controversial aspect of this is the topic of repressed memories. Repressed memory is the idea that traumatic experiences – such as sexual abuse – can be unconsciously blocked for many years such that the individual does not know they were abused, and later recovered in pristine form. The issue of repressed memories has become especially pervasive during the so-called “memory wars”; the ongoing debate between those (often memory scholars) asserting that there is no credible scientific evidence that repressed memories exist and others (often clinicians) claiming that repressed memories do exist. Many scholars have assumed that this debate has been settled, but there is evidence that this debate is far from over (Otgaar et al., 2019).

An important element of the debate concerned situations in which people went to therapy and recovered memories of abuse unknown to them before the therapy started. According to many clinicians, the reason for patients being unaware of an abusive experience was that the memories for that abuse were repressed and that therapy helped recover those memories. However, memory researchers contended that such therapeutic interventions might be inherently suggestive and lead to the creation of false memories of abuse (e.g., Loftus, 1993). Furthermore, another argument was that claims of repressed memories could often be explained by ordinary forgetting (Clancy & McNally, 2005). That is, it is quite normal that people who have experienced a traumatic event will not remember all details of that experience.

Considerable scientific work has been devoted to understanding how false memories are formed and whether repressed memories exist. However, questions have been raised about the ecological validity of false memory research (Blizard & Shaw, 2019). Furthermore, although controversial, the topic of repressed memory continues to be very alive in academic, clinical, and legal circles (for a review, see Otgaar et al., 2019). In the current article, our intention is to set the records straight and provide a brief review of what science tells us about the phenomenon of false and repressed memories. To accomplish this, we will pose several target questions about these phenomena that have frequently been discussed in the literature.

The science behind false memories

We will start with several key points that have frequently been mentioned in the false memory literature. Specifically, we will discuss several issues such as the prevalence of false memory susceptibility and the ecological validity of false memory implantation experiments.

How susceptible are people to forming false memories?

A pertinent issue in false memory studies is individuals’ susceptibility to creating false memories. Importantly, not one answer can be given to this question as different false memory methods have been constructed over the past several decades. For example, false memory production can result from associative processes within the mind (e.g., Deese/Roediger–McDermott false memory task; Deese, 1959; Roediger & McDermott, 1995) or from external suggestions from others (e.g., misinformation paradigm; false memory implantation; Loftus, 2005). For the current article, we will mainly focus on false memories elicited due to suggestions and misinformation because these are often most relevant to the memory wars debate.

One relevant false memory paradigm is the false memory implantation method (e.g., Loftus & Pickrell, 1995). In this method, participants are told to elaborate on events that are suggested to have truly happened to them, where several of the events actually did happen to them, but one event that did not. Using this procedure, researchers have implanted a wide variety of false events, ranging from being lost in shopping mall (Loftus & Pickrell, 1995), to taking a hot air balloon ride (Otgaar et al., 2013; Wade et al., 2002), to being abducted by a UFO (Otgaar et al., 2009), to bumping into a punch bowl at a wedding (Hyman & Billings, 1998). In general, these studies have shown that such suggestions can lead to false autobiographical memories.

When examining the rates at which participants fall prey to these suggestions, studies have found different percentages ranging between 0% (Pezdek et al., 1997) to 70% (Shaw & Porter, 2015; but see also Wade et al., 2018, who found only 30% with different criteria). Wade and colleagues (2002) were one of the first to find that across false memory implantation experiments, the weighted mean percent of false memories was 30%. In a more recent review, Brewin and Andrews (2017) analysed many false memory implantation studies and found full-blown false memories in only 15% of participants. Brewin and Andrews argued that implanting autobiographical false memories is not easy nor common.

An important limitation of Brewin and Andrew’s review was that they collapsed all false memory implantation studies and based on this, calculated a mean percent. False memory implantation studies have used various scoring methods to measure false memory formation and therefore calculating mean percentages is not the most precise estimate of false memory susceptibility. Therefore, Scoboria and colleagues (2017) applied a new coding system to eight previous false memory implantation studies. They found that overall 30.4% of reports were classified as false memories and this percentage increased to 46.1% when the suggestion included self-relevant information, imagination procedures, and was not accompanied by a photo.

Collectively, what research on false memory implantation has shown is that a non-trivial percentage of participants (around 30%) can be swayed into remembering a false autobiographical event. So, in contrast to what is sometimes argued (Brewin & Andrews, 2017), false memory implantation can quite commonly occur when the right conditions are met such as probing guided imagery (see also Nash et al., 2017; Otgaar et al., 2017). Real world therapy scenarios that repeat suggestions over time may yield even higher percentages than experiments that often involve just one or two suggestions.

How ecological valid are false memory implantation studies?

There have been numerous articles in which researchers have debated the ecological validity of false memory experiments (e.g., Ceci et al., 1998; Pezdek & Lam, 2007; Wade et al., 2007). Here we use the classic definition provided by Bronfenbrenner (1977) who stated that “ecological validity refers to the extent to which the environment experienced by the subjects in a scientific investigation has the properties it is supposed or assumed to have by the investigator” (p. 516).

One aim of false memory implantation work is to say something about false memories of traumatic events (e.g., sexual abuse). An important property of false memories of sexual abuse is that these memories often concern emotionally negative events and that such memories sometimes concern repeated events of abuse. Scholars have argued that false memory implantation studies do not meet these criteria. For example, Blizard and Shaw (2019) postulated that false memory researchers have “not been able to implant memories for repeated events, as is often the case with reported childhood sexual abuse” (p. 15). Similarly, Brewin and Andrews (2017) argued that “a challenge for the future will be to demonstrate that it is possible to implant memories of a repeated event” (p. 20).

Concerning the implantation of negative events, research has shown that it is possible to elicit false memories for negative events. For example, Porter and colleagues (1999) succeeded in making people falsely report remembering being bitten by a vicious dog. Also, Shaw and Porter (2015) falsely suggested to participants that they committed a crime (e.g., theft) which led to some apparent false memories. Furthermore, Otgaar et al. (2008) showed that in children, a negative false event (i.e., being accused of copying) was more easily implanted than a neutral false event (i.e., moving to another classroom), a pattern that has been also detected in other false memory paradigms as well (e.g., Bookbinder & Brainerd, 2016). Apart from these examples, researchers have implanted various other negative events in children and adults such as receiving a rectal enema (Otgaar et al., 2010; Pezdek et al., 1999), a finger getting stuck in a mousetrap (Ceci et al., 1994), and being hospitalised (Hyman et al., 1995). Of course, because of obvious ethical reasons, it is not possible to implant events that are even more stressful and negative. However, negative events that have been implanted share certain similarities with sexual abuse such as that the events can be painful (e.g., rectal enema, mousetrap), shameful (e.g., rectal enema), and emotionally arousing (e.g., hospitalisation).

The issue of whether repeated events can be implanted in memory has recently been addressed by Calado and colleagues (2020). In their experiment, they falsely told adult participants that they lost their cuddling toy several times while control participants were told that they only lost it once. Strikingly, they found that repeated false events were as easily inserted in memory as suggesting that the event happened once. So, this study not only showed that repeated events can be implanted, it raised doubts about the idea that repeated events might be harder to implant than single events.

Taken together, although the negative false events used in false memory implantation are still a far stretch from traumatic events that matter in legal cases (such as sexual abuse), an accumulating body of research has shown that the negative events in research do share some properties with the real life events in question.

Science and repressed memories

We will discuss two issues of relevance for the debate on the existence of repressed memories. That is, we will describe research on the evidence, or lack of, for repressed memories and the belief in unconscious repressed memories.

What does science say about the existence of repressed memories?

Influenced by psychoanalytic and hypnotic scholars such as Sigmund Freud and Jean-Martin Charcot, the core proposition behind repressed memories is that they act as a defence mechanism when people experience a traumatic event. Here, the idea is that when traumatic experiences are devastating, the mind automatically and unconsciously banishes this experience from conscious awareness. The purported consequence is that people can no longer recollect the experience that triggered it, and are often unaware that they have been abused or traumatised (Loftus, 1993; McNally, 2005; Piper et al., 2008). The unconscious repressed memory is thought to continuously exert a mental and physical toll, through symptoms, and the chief way to reduce this is by recovering the traumatic content (van der Kolk & Fisler, 1995).

Several plausible alternative explanations have been put forward to explain the apparent forgetting of traumatic incidents (see e.g., McNally, 2005). For example, people who are victimised do not want to talk about or may even forget the traumatic experience, but that does not equate with the unconscious repression of trauma. Second, a well-known phenomenon called the forget-it-all-along effect might explain people’s claims that they have forgotten their traumatic experiences (Arnold & Lindsay, 2002; Schooler et al., 1997). Specifically, according to this phenomenon, some people who claim to have forgotten sexual abuse all-along may not have as further investigation can reveal that they actually disclosed their memory to others, but have forgotten this disclosure. Third, people might not have experienced the event in question as traumatic at the time it happened and later reinterpreted the event as being abusive in retrospect (McNally & Geraerts, 2009). Finally, a voluminous body of research has shown that contrary to the idea underlying the concept of repressed memories, traumatic experiences are in general well remembered (Goodman-Brown et al., 2003; McKinnon et al., 2015; McNally, 2005; Merckelbach et al., 2003; Wagenaar & Groeneweg, 1990).

Some authors have argued that although unconscious repression of autobiographical memories is unlikely, a conscious type of repression might be a plausible alternative to explain the forgetting of traumatic experiences (Anderson & Green, 2001; Anderson & Hulbert, 2020). Oftentimes, instead of the term repression, the term suppression or motivated forgetting is used in this regard (Anderson & Hanslmayr, 2014). Indeed, studies have shown that when participants are instructed to forget or not think of items on a memory test, subsequent memory retrieval of that information is less accurate (Anderson & Hulbert, 2020; Sahakyan et al., 2013). However, a significant limitation with this work is that most of it has focused exclusively on simple stimuli such as words or pictures and there have been failures to replicate these suppression-induced forgetting experiments (e.g., Bulevich et al., 2006; Wessel et al., 2020). Compared with studies on implanted false memories, the ecological validity of work on suppression is lacking.

So, the idea of unconscious repressed memories runs counter to research on how traumatic experiences are stored and retrieved in memory (Engelhard et al., 2019). Plausible alternative explanations exist for why people sometimes claim not to remember traumatic experiences (e.g., reinterpreting memories) and these explanations need to be discussed in the debate on whether repressed memories exist.

Do people believe in the existence of unconscious repressed memories?

A major question in the debate on the existence of repressed memories is whether people actually believe in the concept of repressed memories. To examine this, researchers have asked participants about their beliefs about repressed memories. For example, Merckelbach and Wessel (1998) found that 94% (n = 47) of students indicated some believe in repressed memories. Magnussen and colleagues (2006) surveyed 2000 Norwegian people from the general population and found that 45% (n = 900) endorsed the view that traumatic memories can repressed. Even more recent studies have detected such high endorsement rates. For example, Patihis and colleagues (2014) showed that 81% (n = 316) of a U.S. student sample believed that traumatic memories are often repressed.

However, it was not clear whether the surveyed people were expressing a belief in conscious repression (suppression) or the more controversial idea of unconscious repressed memories (Brewin et al., 2020). Nevertheless, recent survey work found that many people and professionals do indeed endorse the concept of unconscious repression. For example, Houben and colleagues (2020) surveyed eye movement desensitisation and reprocessing (EMDR) therapists as to whether “the mind is capable of unconsciously blocking out memories of traumatic events.” In two studies, Houben and colleagues showed that large percentages of small samples of EMDR therapists agreed with this statement (Study 1: 91.6%, n = 11; Study 2: 70.7%, n = 29).

Furthermore, in a recent study, we specifically asked student participants whether they believed in unconscious repression and found high endorsement rates [Study 1 (N = 230): 59.2% (n = 45); Study 2 (N = 79): 67.1% (n = 53)]; Otgaar et al., 2020). Furthermore, in an extended replication of our work (Dodier et al., in press), participants were also asked about their belief in unconscious repression. The authors also found that many people endorsed the belief in unconscious repression, even more so than for deliberate (conscious) suppression (see Dodier et al., in press). Finally, in another study, we specifically asked what people mean when they believe that traumatic memories can be repressed (Otgaar, Wang, Dodier, et al., 2020). We showed that 80.9% (n = 735) did indeed mean that such repressed memories are unconscious.

In short, the belief in unconscious repressed memories remains well entrenched in the general population and in some clinical contexts. This belief has been and can be hazardous as it might guide therapists to suggestively dig for hidden memories of abuse in their patients.

Concluding remarks

In the current article, we have provided a brief overview of the scientific status of false and repressed memories. Research has clearly shown that false memories can be implanted for autobiographical experiences even when these experiences are emotionally negative and concern repeated events (e.g., Calado et al., 2020; Porter et al., 1999). In contrast, scientific evidence on the existence of unconscious repressed memories is lacking and even empirical work on suppression is deficient, and not ecologically matched to entire autobiographical experiences.

The current overview is timely as there are critiques on the scientific work on false memories and unsupported claims concerning the topic of repressed memories (e.g., Brewin et al., 2020). This might be perilous as there are strong indications that the “memory wars” are far from settled, and that this extends to practice (Patihis & Pendergrast, 2019). We will give two concrete examples. First, the term dissociative amnesia has been referred to as an inability to recall autobiographical memories, ones that mostly originate from stressful or traumatic experiences. This term is currently deeply embedded in the DSM-5 (American Psychiatric Association, 2013) and heavily used in psychological and psychiatric quarters (see Otgaar et al., 2019). However, dissociative amnesia shares many similarities with the controversial topic of repressed memory, but likely because of its inclusion in the DSM-5, has not received as much critical scrutiny. Second, in several European countries (e.g., Belgium, France), statutes of limitations to prosecute sexual crimes have been abolished or extended based on the idea that traumatic memories can be blocked for many years (e.g., Dodier & Tomas, 2019). A negative, but unforeseen, consequence of this abolishment is that falsely recovered memories of abuse allegedly taking place decades ago might find their way in court – potentially leading to false accusations and wrongful convictions.

To conclude, the debate on how traumatic experiences affect memory rages on today and memory scholars should be cognizant of the fact that the controversial issues such as repressed memory (whether conscious or unconscious) oftentimes impact other settings outside of academia such as therapeutic settings and the legal arena. Memory scholars have a responsibility to be aware of these sensitivities and when needed, educate interested parties such as the public and legal system about these controversies. By doing so, there is a chance that fewer false memories of abuse will arise in clients, and prevent false accusations sticking in court.

Features of memory

• On average, about 30% of participants form false memories in implantation studies

• Implanted false memories can occur for negative events and for events that allegedly occurred repeatedly

• Plausible alternative explanations exist in place of unconscious repressed memories such as ordinary forgetting and reinterpreting memories

• Many people continue to believe in the controversial idea of unconscious repressed memories

The Scientific Nature of False and Repressed Memories

The way traumatic events are remembered is a highly debated topic in psychology. A particularly contentious area involves repressed memories, which refers to the theory that traumatic experiences, such as sexual abuse, can be unconsciously blocked from awareness for many years. According to this theory, these memories can later be recovered in their original form. This concept has been central to the "memory wars," an ongoing disagreement between memory researchers, who often state there is no scientific proof for repressed memories, and clinicians, who frequently claim these memories exist. While some scholars believe this debate is resolved, evidence suggests it continues.

A key part of this discussion involves instances where individuals recalled memories of abuse during therapy that were previously unknown to them. Many clinicians suggested that patients were unaware of the abuse because the memories were repressed, and therapy aided their recovery. In contrast, memory researchers argued that such therapeutic methods could be suggestive, potentially leading to the formation of false memories of abuse. Additionally, it has been proposed that what are called repressed memories might simply be instances of normal forgetting. It is common for people who have experienced trauma not to recall every detail of the event.

Significant scientific effort has focused on understanding how false memories develop and if repressed memories truly exist. However, the real-world applicability, or ecological validity, of false memory research has been questioned. Despite its controversial nature, the subject of repressed memory remains relevant in academic, clinical, and legal settings. This discussion aims to clarify the scientific understanding of false and repressed memories by addressing key questions often found in the literature.

How Susceptible Are People to Forming False Memories?

A crucial area in the study of false memories is understanding how easily individuals can form them. There is no single answer to this question, as various methods for studying false memories have been developed over decades. False memories can arise from mental associative processes or from external suggestions and misinformation from others, such as in false memory implantation. This discussion focuses primarily on false memories caused by suggestion and misinformation, as these are most relevant to the "memory wars" debate.

The false memory implantation method is a key research approach. In this method, participants are prompted to describe events that are suggested to have occurred in their past. Some of these events are real, but one is fabricated. Through this process, researchers have successfully implanted various false memories, such as being lost in a shopping mall, experiencing a hot air balloon ride, being abducted by a UFO, or bumping into a punch bowl at a wedding. Generally, these studies demonstrate that suggestions can result in individuals forming false autobiographical memories.

Studies exploring the rate at which participants accept these suggestions have shown varying percentages, from 0% to 70%. Early research indicated that the average rate of false memories across implantation experiments was approximately 30%. However, a more recent review of many false memory implantation studies reported that only 15% of participants formed complete false memories. The authors of that review suggested that implanting autobiographical false memories is neither simple nor frequent.

A significant limitation of the aforementioned review was its method of combining all false memory implantation studies to calculate an average percentage. Different false memory studies employ various scoring techniques to assess false memory formation, making a simple average percentage an imprecise measure of susceptibility. Subsequent research applied a new coding system to eight prior studies and found that 30.4% of reported memories were false. This percentage rose to 46.1% when the suggestion included self-relevant information, involved imagination, and was not accompanied by a photo.

In summary, research on false memory implantation demonstrates that a notable percentage of participants, approximately 30%, can be led to recall a false autobiographical event. This suggests that, contrary to some arguments, false memory implantation can occur quite frequently under specific conditions, such as the use of guided imagery. Real-world therapeutic settings, where suggestions may be repeated over time, could potentially result in even higher percentages than typical experiments that involve only one or two suggestions.

How Ecologically Valid Are False Memory Implantation Studies?

Numerous discussions among researchers have addressed the ecological validity of false memory experiments. Ecological validity refers to how accurately the environment and conditions of a scientific study reflect real-world situations, as intended by the researchers.

A goal of false memory implantation research is to provide insights into false memories of traumatic experiences, such as sexual abuse. These traumatic false memories often involve emotionally negative content and, sometimes, repeated occurrences of abuse. Critics have argued that false memory implantation studies typically fail to meet these specific criteria. Some scholars have stated that researchers have not been able to implant memories for repeated events, which is frequently a characteristic of reported childhood sexual abuse.

Regarding the implantation of negative events, research indicates that creating false memories for such events is possible. For instance, studies have successfully led individuals to falsely recall being bitten by a dog or committing a minor crime like theft. Research with children has shown that a negative false event, such as being accused of copying, was easier to implant than a neutral one, like moving classrooms. Other negative false memories implanted in children and adults include receiving a rectal enema, having a finger stuck in a mousetrap, and being hospitalized. While ethical considerations prevent the implantation of more severely traumatic events, the negative events used in research share qualities with sexual abuse, such as being painful, shameful, or emotionally distressing.

The question of whether repeated false events can be implanted in memory has also been explored. One study falsely informed adult participants that they had lost a toy multiple times, while a control group was told the event happened only once. The findings revealed that repeated false events were implanted just as easily as single false events. This study not only demonstrated the possibility of implanting repeated events but also challenged the notion that such events might be more difficult to implant than single occurrences.

In summary, while the negative false events used in research are not equivalent to the traumatic events relevant in legal cases, a growing body of evidence suggests that these research events do share some characteristics with real-life traumatic experiences.

What Does Science Say About the Existence of Repressed Memories?

This discussion focuses on the scientific evidence for, or lack thereof, and the public belief in unconscious repressed memories. The central idea of repressed memories, influenced by figures like Freud and Charcot, proposes that they serve as a defense mechanism following trauma. When traumatic experiences are overwhelming, the mind is thought to automatically and unconsciously block them from conscious awareness. As a result, individuals reportedly cannot recall the original event and may not realize they were abused or traumatized. These unconscious repressed memories are believed to cause ongoing mental and physical symptoms, which are purportedly alleviated by recovering the traumatic content.

Several credible alternative explanations account for the apparent forgetting of traumatic events. First, individuals who have experienced trauma may choose not to discuss it or may simply forget the experience, but this does not imply unconscious repression. Second, the "forget-it-all-along" effect suggests that people claiming to have always forgotten traumatic experiences, such as sexual abuse, might have actually disclosed them but later forgot having done so. Third, some individuals may not have initially perceived an event as traumatic but later reinterpreted it as abusive in retrospect. Finally, extensive research indicates that, contrary to the concept of repressed memories, traumatic experiences are generally well-remembered.

Some researchers have proposed that while unconscious repression of autobiographical memories is improbable, a conscious form of repression, often called suppression or motivated forgetting, might explain forgotten traumatic experiences. Studies have demonstrated that when participants are told to forget specific items during a memory test, their ability to recall that information later is reduced. However, this research is significantly limited because it primarily uses simple stimuli like words or pictures, and some experiments on suppression-induced forgetting have not been replicated successfully. The ecological validity of suppression research is also lower compared to studies on implanted false memories.

Therefore, the concept of unconscious repressed memories contradicts current research on how traumatic experiences are encoded and retrieved in memory. Credible alternative explanations, such as reinterpreting memories, exist for why individuals sometimes report not remembering traumatic experiences. These alternatives warrant careful consideration in discussions about the existence of repressed memories.

Do People Believe in the Existence of Unconscious Repressed Memories?

A significant aspect of the repressed memory debate concerns the extent to which the public believes in this concept. Surveys have been conducted to assess these beliefs. For instance, an early study found that 94% of students reported some belief in repressed memories. A larger survey of 2000 Norwegian adults revealed that 45% agreed that traumatic memories can be repressed. More recent studies continue to show high endorsement rates; for example, 81% of a U.S. student sample believed that traumatic memories are frequently repressed.

It was initially unclear if these surveys reflected a belief in conscious repression (suppression) or the more contentious idea of unconscious repressed memories. However, more recent research indicates that many individuals and professionals do specifically endorse the concept of unconscious repression. For instance, a study asked EMDR therapists if "the mind is capable of unconsciously blocking out memories of traumatic events." A high percentage of therapists in two studies agreed with this statement.

Additionally, a recent study directly asked student participants about their belief in unconscious repression, revealing high endorsement rates (59.2% and 67.1% in two separate studies). An expanded replication also found that many people endorsed belief in unconscious repression, even more so than for conscious suppression. Another study investigated what individuals mean when they believe traumatic memories can be repressed, showing that 80.9% intended to mean that such memories are unconscious.

In summary, the belief in unconscious repressed memories is deeply rooted within the general population and certain clinical fields. This belief poses potential risks, as it might lead therapists to use suggestive methods to uncover hidden memories of abuse in their patients.

Concluding Remarks

This overview has examined the scientific standing of false and repressed memories. Research consistently demonstrates that false memories for autobiographical events can be implanted, even for experiences that are emotionally negative or involve repeated occurrences. Conversely, there is a lack of scientific evidence supporting the existence of unconscious repressed memories, and empirical work on memory suppression is limited and often does not reflect full autobiographical experiences in real-world contexts.

This review is particularly relevant given ongoing criticisms of false memory research and unsubstantiated claims regarding repressed memories. This situation is potentially hazardous, as indications suggest the "memory wars" are far from over and continue to impact practical applications. For example, dissociative amnesia, defined as the inability to recall autobiographical memories, often stemming from stressful or traumatic experiences, is firmly established in diagnostic manuals like the DSM-5 and widely used in psychology and psychiatry. Despite its resemblance to the contentious topic of repressed memory, dissociative amnesia has not faced similar critical examination, possibly due to its official classification. Additionally, several European countries have eliminated or extended statutes of limitations for prosecuting sexual crimes, based on the belief that traumatic memories can be blocked for many years. An unintended negative consequence of such changes is the potential for falsely recovered memories of alleged abuse from decades past to be presented in court, possibly leading to false accusations and wrongful convictions.

In conclusion, the debate concerning the impact of traumatic experiences on memory persists. Memory researchers must recognize that controversial issues like repressed memory, whether conscious or unconscious, frequently influence areas beyond academia, including therapeutic and legal contexts. Scholars have a responsibility to understand these sensitivities and, when necessary, to inform interested parties, such as the public and the legal system, about these controversies. Such efforts could potentially reduce the emergence of false memories of abuse in clients and prevent false accusations from leading to convictions.

Key Findings on Memory

• Approximately 30% of participants in implantation studies form false memories on average.

• False memories can be implanted for negative events and for events reported to have happened repeatedly.

• Credible alternative explanations exist for the apparent forgetting of traumatic experiences, distinct from unconscious repression, such as normal forgetting and memory reinterpretation.

• The controversial idea of unconscious repressed memories continues to be widely believed by many individuals.

The Scientific Nature of False and Repressed Memories

How traumatic experiences are remembered is a highly debated topic in psychology. A particularly controversial area is the concept of repressed memories. This idea suggests that traumatic events, like sexual abuse, can be unconsciously blocked for many years, causing an individual to be unaware of the abuse. These memories are then supposedly recovered in their original form later. Repressed memories gained prominence during the "memory wars," an ongoing dispute between memory researchers who question their scientific basis and clinicians who assert their existence. While some believe this debate is resolved, evidence suggests it continues.

An important part of this debate involves situations where individuals in therapy recovered memories of abuse that were previously unknown to them. Many clinicians propose that the lack of awareness stemmed from repressed memories that therapy helped retrieve. However, memory researchers argue that such therapeutic methods might be suggestive, potentially leading to the creation of false memories of abuse. Additionally, another explanation for claims of repressed memories is ordinary forgetting. It is common for individuals who have experienced trauma not to remember every detail of the event.

Much scientific effort has focused on understanding how false memories are formed and whether repressed memories truly exist. Still, questions have been raised about how well false memory research applies to real-life situations. Despite the controversy, the topic of repressed memory remains relevant in academic, clinical, and legal discussions. This review aims to clarify what science currently indicates about false and repressed memories by addressing frequently discussed questions.

The Science Behind False Memories

Key points from research on false memories are important to understand. This section addresses how easily people form false memories and how well laboratory studies of false memory creation reflect real-world situations.

How susceptible are people to forming false memories?

A crucial question in false memory research concerns how easily individuals can create false memories. There is no single answer, as various methods for studying false memory have been developed over decades. For instance, false memories can arise from associative processes within the mind or from external suggestions from others, such as through misinformation. For this discussion, the focus will be on false memories caused by suggestions and misinformation, as these are often most relevant to the "memory wars" debate.

One important false memory method is false memory implantation. In this procedure, participants are encouraged to describe events that are suggested to have happened to them. Some of these events are real, but one is fabricated. Using this approach, researchers have successfully implanted a wide range of false events, including being lost in a shopping mall, taking a hot air balloon ride, being abducted by a UFO, or bumping into a punch bowl at a wedding. Generally, these studies demonstrate that such suggestions can lead to false autobiographical memories.

When looking at how often participants are influenced by these suggestions, studies have reported varying percentages, from 0% to 70%. Early research found that, on average, 30% of false memory implantation experiments resulted in false memories. A more recent analysis of many such studies found clear false memories in only 15% of participants. Researchers who conducted this review argued that implanting autobiographical false memories is not common or easy.

A limitation of that review was its calculation of an average percentage by combining all false memory implantation studies, despite their use of different scoring methods. Such a calculation may not be the most precise way to estimate how susceptible people are to false memories. Therefore, other researchers applied a new coding system to eight previous studies and found that 30.4% of reports were classified as false memories. This percentage increased to 46.1% when suggestions included self-relevant information, imagination techniques, and no accompanying photo.

Overall, research on false memory implantation indicates that a significant number of participants (around 30%) can be persuaded to remember a false autobiographical event. This suggests that, contrary to some claims, false memory implantation can happen quite often when specific conditions are met, such as using guided imagery. Real-world therapy settings that involve repeated suggestions over time might even produce higher percentages than experiments, which often use only one or two suggestions.

How ecologically valid are false memory implantation studies?

Many articles have debated how well false memory experiments apply to real-world situations, a concept known as ecological validity. Ecological validity refers to how accurately the conditions experienced by study participants reflect the real-world situations they are meant to represent.

A goal of false memory implantation research is to provide insights into false memories of traumatic events, such as sexual abuse. A key feature of false memories of sexual abuse is that they often involve emotionally negative experiences and sometimes concern repeated incidents. Some experts argue that current false memory implantation studies do not meet these criteria, noting that researchers have not been able to implant memories for repeated events, which is often the case with reported childhood sexual abuse. They suggest that demonstrating the ability to implant memories of a repeated event is a future challenge for the field.

Regarding the implantation of negative events, research shows that it is possible to create false memories for such experiences. For example, studies have successfully made people falsely remember being bitten by a vicious dog or committing a crime like theft. Other research suggests that negative false events (e.g., being accused of copying) might be easier to implant in children than neutral ones (e.g., moving classrooms), a pattern also observed in other false memory studies. While ethical considerations prevent the implantation of highly stressful and negative events, researchers have implanted various other negative events in children and adults, such as receiving a rectal enema, getting a finger stuck in a mousetrap, and being hospitalized. These implanted negative events share some characteristics with sexual abuse, such as being painful, shameful, or emotionally arousing.

The question of whether memories of repeated events can be implanted has also been addressed. In one experiment, adult participants were falsely told they had lost a cuddling toy multiple times, while control participants were told it happened only once. Remarkably, the study found that repeated false events were just as easily implanted in memory as single events. This research not only shows that repeated events can be implanted but also challenges the idea that they might be harder to implant than single occurrences.

In summary, while the negative false events used in false memory implantation studies are still quite different from the traumatic events involved in legal cases (like sexual abuse), a growing body of research indicates that these experimental negative events do share some characteristics with real-life traumatic experiences.

Science and Repressed Memories

This section addresses two important aspects of the debate on repressed memories: the scientific evidence (or lack thereof) for their existence and how widely people believe in unconscious repressed memories.

What does science say about the existence of repressed memories?

Influenced by psychoanalytic and hypnotic theories, the central idea behind repressed memories is that they serve as a defense mechanism when individuals experience trauma. It is believed that if traumatic experiences are too devastating, the mind automatically and unconsciously removes them from conscious awareness. The supposed result is that individuals can no longer recall the event and are often unaware they were abused or traumatized. These unconscious repressed memories are thought to cause ongoing mental and physical distress through various symptoms, with recovery of the traumatic content being the primary way to alleviate these issues.

Several alternative explanations have been proposed to account for the apparent forgetting of traumatic incidents. For example, individuals who have been victimized might simply prefer not to discuss or even forget a traumatic experience, but this is not the same as unconscious repression of trauma. Second, a phenomenon known as the "forget-it-all-along effect" may explain claims of forgotten traumatic experiences. According to this effect, some individuals who claim to have always forgotten sexual abuse might have actually disclosed the memory to others but have since forgotten making that disclosure. Third, people might not have initially considered an event traumatic but later reinterpreted it as abusive in retrospect. Finally, extensive research indicates that, contrary to the concept of repressed memories, traumatic experiences are generally well remembered.

Some experts have suggested that while unconscious repression of autobiographical memories is unlikely, a conscious form of repression might explain the forgetting of traumatic experiences. Often, the terms "suppression" or "motivated forgetting" are used in this context. Studies have shown that when participants are instructed to forget or avoid thinking about items on a memory test, their subsequent recall of that information is less accurate. However, a major limitation of this work is that it mostly focuses on simple stimuli like words or pictures, and some attempts to replicate these suppression-induced forgetting experiments have failed. Compared to studies on implanted false memories, the real-world applicability of research on suppression is lacking.

Thus, the idea of unconscious repressed memories goes against current research on how traumatic experiences are stored and retrieved in memory. Plausible alternative explanations exist for why people sometimes claim not to remember traumatic experiences, such as reinterpreting memories. These explanations need to be considered in discussions about the existence of repressed memories.

Do people believe in the existence of unconscious repressed memories?

A significant question in the debate about repressed memories is whether the general population actually believes in this concept. To investigate this, researchers have surveyed people about their beliefs. For example, an early study found that 94% of students expressed some belief in repressed memories. A survey of 2000 Norwegian adults revealed that 45% endorsed the view that traumatic memories can be repressed. Even more recent studies have shown high rates of agreement. For instance, a study of U.S. students indicated that 81% believed traumatic memories are often repressed.

However, it was not always clear if surveyed individuals were referring to conscious repression (suppression) or the more controversial idea of unconscious repressed memories. Nevertheless, recent survey work confirms that many people and professionals do indeed endorse the concept of unconscious repression. For example, a study of eye movement desensitization and reprocessing (EMDR) therapists asked if "the mind is capable of unconsciously blocking out memories of traumatic events." In two studies, large percentages of these therapists agreed with this statement (91.6% in one study and 70.7% in another).

Furthermore, a recent study specifically asked student participants if they believed in unconscious repression and found high endorsement rates (59.2% and 67.1% in two separate studies). An extended replication of this work also found that many people endorsed the belief in unconscious repression, even more so than for deliberate (conscious) suppression. Finally, in another study, researchers specifically asked what people meant when they said they believed traumatic memories could be repressed. It was shown that 80.9% of participants understood such repressed memories to be unconscious.

In summary, the belief in unconscious repressed memories remains deeply rooted in the general public and in some clinical settings. This belief has been, and can be, risky because it might lead therapists to suggestively search for hidden memories of abuse in their patients.

Concluding Remarks

This article has provided a brief overview of the scientific understanding of false and repressed memories. Research clearly demonstrates that false memories for autobiographical experiences can be implanted, even when these experiences are emotionally negative and involve repeated events. In contrast, scientific evidence for the existence of unconscious repressed memories is lacking, and even empirical work on suppression is insufficient and does not fully reflect real-life autobiographical experiences.

This overview is timely due to ongoing criticisms of scientific work on false memories and unsubstantiated claims regarding repressed memories. This situation can be dangerous, as there are strong indications that the "memory wars" are far from settled, and these issues extend into practical applications. For instance, "dissociative amnesia" refers to an inability to recall autobiographical memories, often stemming from stressful or traumatic experiences. This term is deeply integrated into diagnostic manuals and widely used in psychology and psychiatry. However, dissociative amnesia shares many similarities with the controversial topic of repressed memory but has not received as much critical examination, likely due to its formal inclusion in diagnostic criteria. Secondly, in several European countries, limitations on how long after a crime sexual offenses can be prosecuted have been removed or extended. This decision is based on the idea that traumatic memories can be blocked for many years. An unintended and negative consequence of this change is that falsely recovered memories of abuse, supposedly from decades ago, might be presented in court, potentially leading to false accusations and wrongful convictions.

In conclusion, the debate over how traumatic experiences affect memory continues today. Memory scholars should recognize that controversial issues like repressed memory, whether conscious or unconscious, often impact settings outside of academia, such as therapeutic and legal environments. Scholars have a responsibility to be aware of these sensitivities and, when necessary, educate interested parties like the public and the legal system about these controversies. By doing so, there is a chance that fewer false memories of abuse will emerge in clients, and false accusations will be less likely to hold up in court.

Features of Memory

• On average, about 30% of participants form false memories in implantation studies.

• Implanted false memories can occur for negative events and for events that allegedly occurred repeatedly.

• Plausible alternative explanations exist instead of unconscious repressed memories, such as ordinary forgetting and reinterpreting memories.

• Many people continue to believe in the controversial idea of unconscious repressed memories.

The Scientific Nature of False and Repressed Memories

How people remember traumatic experiences is a highly debated topic in psychology. One very controversial area is the idea of repressed memories. This concept suggests that traumatic events, such as abuse, can be unconsciously blocked from memory for many years, making a person unaware they occurred. Later, these memories are believed to be recovered in a perfect state. This issue has led to intense discussions, often called the "memory wars," between researchers who see no scientific proof for repressed memories and clinicians who believe they exist. While some think the debate is settled, evidence shows it continues.

Part of this discussion involves situations where people in therapy recall abuse they did not remember before treatment. Some clinicians believe therapy helps recover these repressed memories. However, memory researchers argue that such therapy might accidentally suggest events, leading to the creation of false memories of abuse. Another explanation is that claims of repressed memories could simply be ordinary forgetting, as it is normal not to remember every detail of a traumatic event. Extensive scientific work has explored how false memories form and whether repressed memories are real. Despite ongoing questions, the topic remains important in academic, clinical, and legal discussions.

The Science Behind False Memories

Research has explored how easily people can form false memories. It is important to note that different methods of creating false memories exist. For instance, false memories can arise from how the mind connects ideas or from external suggestions. This discussion focuses mainly on false memories caused by suggestions, as they are most relevant to the "memory wars" debate.

One key research method involves suggesting false events to participants, such as being lost in a shopping mall or taking a hot air balloon ride. Studies using this approach have shown that people can be led to "remember" these false personal experiences. The percentage of participants who form false memories in these studies varies, but a significant number, often around 30%, can be convinced to recall an event that never happened. These findings suggest that creating false memories is not uncommon under certain conditions, such as using guided imagery, and that real-world situations with repeated suggestions might lead to even higher rates.

Concerns have been raised about whether these studies accurately reflect real-life situations, especially traumatic events like abuse. Critics question if false memory research can implant memories for emotionally negative or repeated events, which are often characteristics of abuse. However, studies have shown it is possible to create false memories for negative events, such as being bitten by a dog or committing a crime. Researchers have also successfully implanted memories of repeated events. While the negative events in these studies are not as severe as real-life trauma, they do share some emotional and physical qualities.

Science and Repressed Memories

The core idea of repressed memories, influenced by early psychological theories, is that the mind automatically and unconsciously blocks traumatic experiences as a defense mechanism. This means a person would not be able to recall the event and might not even know they were abused. These unconscious memories are believed to cause ongoing distress, which can only be relieved by recovering the memory.

However, several alternative explanations exist for why people might not remember traumatic incidents. For example, people might consciously avoid talking about or forget painful experiences, which is different from unconscious repression. Another explanation is the "forget-it-all-along" effect, where someone might forget they once remembered or disclosed a traumatic event. Additionally, a person might not have seen an event as traumatic at the time, only reinterpreting it as abusive later. Contrary to the idea of repression, much research indicates that traumatic experiences are generally well-remembered. While some research explores conscious motivated forgetting, its ecological relevance to entire traumatic experiences is limited.

Despite the lack of scientific evidence for unconscious repressed memories, many people continue to believe in them. Surveys show high percentages of the general population and even some therapists endorse the idea that traumatic memories can be unconsciously blocked. This belief can be risky if it leads therapists to suggestively search for hidden memories of abuse in their patients.

Concluding Remarks

Research clearly shows that false memories can be implanted for personal experiences, even if these events are emotionally negative or happened repeatedly. In contrast, there is limited scientific evidence to support the existence of unconscious repressed memories. This ongoing "memory wars" debate has significant effects beyond academia, influencing therapeutic practices and legal decisions. For instance, the term "dissociative amnesia," which describes an inability to recall traumatic memories and is included in a widely used diagnostic manual, shares similarities with repressed memory but receives less criticism. Also, changes in laws regarding statutes of limitations for sexual crimes in some countries are partly based on the idea that traumatic memories can be blocked for many years. This could lead to false accusations in court from falsely recovered memories.

Memory scholars have a responsibility to inform the public and legal system about these controversies. By doing so, there is a chance to reduce the creation of false memories of abuse in clients and prevent wrongful convictions.

The Scientific Facts About False and Hidden Memories

How people remember very bad experiences is a much-debated topic in psychology. One part of this debate is about "repressed memories." This is the idea that terrible events, like abuse, can be completely blocked from a person's mind without them knowing. Years later, these memories might come back exactly as they happened. This idea has led to big arguments among experts, sometimes called "memory wars." Some scientists say there is no real proof that repressed memories exist, while some therapists believe they do. This debate is still ongoing.

Many years ago, some people went to therapy and then remembered abuse they had not known about before. Some therapists said this was because the memories were repressed and therapy helped bring them back. But memory scientists argued that therapy could sometimes plant false memories of abuse. They also said that people might just forget things over time, which is normal after a bad event. It is common for people not to remember every single detail of a difficult experience.

A lot of science has looked into how false memories are made and if repressed memories are real. Questions have been raised about whether false memory studies truly show what happens in real life. Still, the topic of repressed memory is important in schools, clinics, and courts. This information explains what science tells us about false and repressed memories.

The Science Behind False Memories

This section looks at some important points about false memories. It covers how easily people can form false memories and how well lab studies match real-life events.

How Easy Is It for People to Form False Memories?

It is important to know how easily people can create false memories. There is no single answer, as different ways of studying this have been used. For example, false memories can come from how the mind connects ideas, or from what other people suggest. This information will mostly look at false memories caused by suggestions, as this is often most important in the memory debates.

One common way to study false memories is called the "false memory implantation method." In this method, people are told to think about events that supposedly happened to them. Some events truly happened, but one did not. Using this method, researchers have planted many types of false memories. These include remembering being lost in a mall, taking a hot air balloon ride, being taken by a UFO, or bumping into a punch bowl at a wedding. These studies generally show that suggestions can make people remember false personal events.

When scientists look at how many people fall for these suggestions, the numbers change. Some studies show no false memories, while others show up to 70%. One early study found that about 30% of people formed false memories. A later review of many studies found that only 15% of people formed complete false memories. This review suggested that planting false personal memories is not easy or common.

However, the later review looked at all studies together, even if they used different ways to measure false memories. A more recent study used a new way to score these tests. It found that about 30% of memories were false. This number went up to 46% when the suggestion was about something personal, used imagination, and did not include a photo.

Overall, research on planting false memories shows that a fair number of people (around 30%) can be led to remember a false personal event. So, planting false memories can happen often, especially when conditions are right, like using guided imagination. In real-life therapy, where suggestions might be repeated many times, this percentage could be even higher.

How Much Do False Memory Studies Match Real Life?

Many articles have discussed how well false memory studies match real-life situations. "Ecological validity" means how much the study setting is like the real world it is trying to understand.

One goal of false memory studies is to learn about false memories of traumatic events, like abuse. An important part of false memories of abuse is that they are often about very negative events and sometimes about events that happened many times. Some experts have said that false memory studies do not include these points. For example, some argue that researchers have not been able to plant memories for events that happened many times, which is often the case with child abuse. They also say it is a challenge to plant memories of a repeated event.

When it comes to planting memories of negative events, research shows this is possible. For example, studies have made people falsely remember being bitten by a dangerous dog or committing a crime like theft. Other studies found that a negative false event, like being accused of cheating, was easier to plant than a neutral one. Researchers have also planted other negative events in children and adults, such as getting a medical procedure, a finger getting stuck in a mousetrap, or being in the hospital. Of course, due to rules about what is right and wrong, it is not possible to plant even more stressful events. But the negative events used in studies do share some traits with abuse, like being painful, shameful, or very emotional.

The question of whether repeated events can be planted in memory has also been looked at. One study falsely told adults they had lost their favorite toy many times, while others were told they lost it once. Surprisingly, it was just as easy to plant false memories for repeated events as for single events. This study showed that repeated false events can be planted and raised doubts about the idea that they might be harder to plant.

In summary, while the negative false events in studies are still different from real traumatic events in court cases, a growing amount of research shows that these study events do share some traits with real-life bad experiences.

Science and Repressed Memories

This section talks about two important issues regarding whether repressed memories exist. It looks at the proof, or lack of proof, for repressed memories and whether people believe in unconscious repressed memories.

What Does Science Say About Repressed Memories?

The main idea behind repressed memories comes from thinkers like Sigmund Freud. It says that the mind hides a traumatic event as a way to protect itself. When bad experiences are too much to handle, the mind automatically and without a person knowing, pushes the memory away. Because of this, people cannot remember the event and often do not know they were abused or hurt. This hidden memory is thought to cause ongoing mental and physical problems. The main way to stop these problems is to remember the traumatic event.

However, other good reasons have been given for why people might forget bad events. For example, victims might not want to talk about or might even forget a traumatic experience, but this is not the same as the mind automatically hiding it. Second, some people say they have forgotten abuse "all along," but later information shows they actually told others about it before, and just forgot that they told someone. Third, people might not have thought an event was traumatic when it happened, but later they look back and decide it was abuse. Finally, a lot of research shows that, generally, people remember traumatic experiences quite well, which goes against the idea of repressed memories.

Some experts have said that while unconscious repression (forgetting without knowing) is unlikely, a conscious type of repression (trying to forget on purpose) might explain why people forget traumatic events. This is often called "suppression" or "motivated forgetting." Studies have shown that when people are told to forget certain things in a memory test, they remember those things less well later. However, most of this research has only used simple things like words or pictures, and some studies have not been able to repeat these findings. Compared to studies on false memories, the real-life value of work on suppression is not as strong.

So, the idea of unconscious repressed memories does not match what research tells us about how traumatic events are remembered. Other good reasons exist for why people sometimes say they do not remember traumatic events, such as reinterpreting past memories. These other reasons need to be part of the discussion about whether repressed memories are real.

Do People Believe in Unconscious Repressed Memories?

A big question in the debate about repressed memories is whether people actually believe in them. To find out, researchers have asked people about their beliefs. For example, one study found that 94% of students believed in repressed memories. Another study of 2000 adults found that 45% believed traumatic memories could be repressed. Even more recent studies show high numbers, with 81% of students in one study believing that traumatic memories are often repressed.

However, it was not always clear if people meant conscious forgetting (suppression) or the more debated idea of unconscious repressed memories. But recent surveys found that many people and even some professionals do believe in unconscious repression. For example, therapists were asked if "the mind is capable of unconsciously blocking out memories of traumatic events." In two studies, a large number of these therapists agreed.

Other recent studies specifically asked students if they believed in unconscious repression and found high belief rates. Even more, one study asked what people meant when they said traumatic memories could be repressed, and 80.9% said they meant these memories are unconscious.

In short, the belief in unconscious repressed memories is still strong among the general public and in some therapy settings. This belief can be risky because it might lead therapists to suggest hidden memories of abuse to their patients, even if those memories are not real.

Final Thoughts

This information has given a quick look at what science says about false and repressed memories. Research clearly shows that false memories can be planted for personal events. This can happen even if the events are negative or are said to have happened many times. On the other hand, there is not much scientific proof for unconscious repressed memories. Also, studies on conscious suppression do not often match real-life experiences completely.

This overview is important because there are questions about false memory research and claims about repressed memories that are not supported by science. This can be dangerous because it seems the "memory wars" are still active and affect real life. For example, "dissociative amnesia" is a term for not being able to remember personal traumatic events. This term is used in mental health guides and by many doctors, but it is similar to the idea of repressed memory. Yet, it has not been questioned as much. Also, in some countries, laws that limit how long someone can be charged with a crime have been removed or changed. This is based on the idea that traumatic memories can be hidden for many years. A bad result of this could be that false memories of abuse from long ago might end up in court. This could lead to false accusations and wrongful convictions.

To sum up, the debate about how traumatic events affect memory is still happening. Experts who study memory need to remember that these difficult issues, like repressed memory, often impact other areas beyond school, such as therapy and legal cases. Memory scientists have a duty to understand these sensitive topics and, when needed, teach the public and the legal system about these arguments. By doing so, there is a chance that fewer false memories of abuse will appear in clients, and fewer false accusations will succeed in court.

Important Points About Memory

• About 30% of people in studies form false memories when suggestions are made.

• False memories can be planted for negative events and for events said to have happened many times.

• Good reasons other than unconscious repressed memories can explain why people forget, such as normal forgetting or changing how they see past events.

• Many people still believe in the idea of unconscious repressed memories.