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'''Recovered memory''' is the description given to the apparent [[memory]] of event(s) that, if they occurred at all, was previously apparently forgotten for a relatively lomg time. People sometimes report recovering long-forgotten memories of, for example, childhood sexual abuse. The  mechanisms that lead to such reports are not well understood, and the authenticity of recovered memories has often been challenged; in some cases, recovered memories are fictitious, although in other cases they may be authentic.
'''Recovered memory''' is the apparent resurrection of the [[memory]] of events that had been forgotten or suppressed for a long time. [[Retrograde amnesia]] after physical or emotional trauma (i.e., [[traumatic amnesia]]), or the suppression of painful memories from any cause, is well known. However the mechanisms that lead to recovery of long forgotten memories are not well understood, and the authenticity of these recovered memories has often been challenged; in some cases recovered memories are fictitious, although in other cases they may be authentic.<ref>Geraerts E ''et al.'' (2009) Cognitive mechanisms underlying recovered-memory experiences of childhood sexual abuse. ''Psychol Sci'' 20:92-8 PMID 19037903 </ref> <ref name=Brewin>Brewin CR, Andrews B (1998) Recovered memories of trauma: phenomenology and cognitive mechanisms. ''Clin Psychol Rev'' 18:949-70. PMID 9885769 </ref>  
<ref>Geraerts E ''et al.'' (2009)Cognitive mechanisms underlying recovered-memory experiences of childhood sexual abuse. ''Psychol Sci'' 20:92-8. PMID 19037903</ref><ref>Geraerts E, McNally RJ (2008) Forgetting unwanted memories: directed forgetting and thought suppression methods. ''Acta Psychol (Amst)'' 127:614-22. PMID 18164273</ref> <ref>Brewin CR, Andrews B (1998) Recovered memories of trauma: phenomenology and cognitive mechanisms. ''Clin Psychol Rev'' 18:949-70. PMID 9885769</ref>


The issues surrounding recovered, or false memories have sparked "one of the greatest controversies in the mental health profession in the 20th century".<ref>Loftus EF, Davis D (2006) Recovered memories. ''Annu Rev Clin Psychol'' 2:469-98. PMID 17716079 </ref>  
The issues surrounding recovered, or false memories have sparked one of the greatest controversies in the mental health profession of recent times.<ref>Loftus EF, Davis D (2006) Recovered memories ''Annu Rev Clin Psychol'' 2:469-98. PMID 17716079  
Some therapists have suggested that memories of extreme trauma are buried in the [[subconscious]] by some special process, and are later reliably recovered, but others consider that the evidence to support this claim is flawed. Various manipulations can be used to implant false memories of traumatic events that can be quite compelling for those who develop them and can include details that make them seem credible to others.
</ref> Some researchers have proposed that memories of extreme trauma are buried in the [[subconscious]] by a special process, and are later reliably recovered. Others consider that genuinely traumatic events are seldom truly forgotten, and that the scientific evidence indicates that traumatic amnesia is a myth.<ref>Gibbs AA, David AS (2003) Delusion formation and insight in the context of affective disturbance. </ref> <ref>Goodyear-Smith FA ''et al.'' (1997) Memory recovery and repression: what is the evidence? ''Health Care Anal'' 5:99-111 PMID 10167722</ref> However, traumatized individuals exhibit a range of memory impairments, and research on children's and adults' encoding and memory of trauma stimuli has provided some support for models of repression and traumatic amnesia.<ref>See Policy Forum in ''Science'' (2005) and ensuing correspondence. Freyd JJ ''et al.'' (2005) Psychology. The science of child sexual abuse. ''Science'' (Policy Forum) 308:501 PMID 15845837 Quote from Kihlstrom JF ''et al.'' in response in ''Science'' 309:1182-5 PMID 16114120 with authors' reply</ref>
<ref>Laney C, Loftus EF (2005) Traumatic memories are not necessarily accurate memories. ''Can J Psychiatry'' 50:823-8. PMID 16483115</ref><ref>Pezdek K, Lam S (2007) What research paradigms have cognitive psychologists used to study "false memory," and what are the implications of these choices? ''Conscious Cogn'' 16:2-17. PMID 16157490 </ref> Serious issues arise when recovered but false memories result in public allegations <ref>Boakes J (1999) False complaints of sexual assault: recovered memories of childhood sexual abuse. ''Med Sci Law'' 39:112-20. PMID 10332158 ''("False complaints are easily made and carry serious consequences for the accused. Many of those who make false claims sincerely believe the truth of what they report... A special type of false allegation, the false memory syndrome, arises typically within therapy. People report the 'recovery' of memories of previously unknown childhood sexual abuse. The influence of practitioners' beliefs and practices in the eliciting of false 'memories' and of false complaints cannot be overlooked.")''</ref> or are used as evidence in criminal prosecutions<ref>Porter S ''et al.''(2001) Memory for murder. A psychological perspective on dissociative amnesia in legal contexts. ''Int J Law Psychiatry'' 24:23-42. PMID 11346990 ''("...The uncritical acceptance of the validity of repressed memories in complainants by many courts stands in stark contrast to the response to claims of amnesia from defendants. It seems apparent that the courts need better guidelines around the issue of dissociative amnesia in both populations.")''</ref>


The growth in the USA of 'recovered memory therapy' for past sexual abuse has caused great public and professional concern.when memories are 'recovered' after long periods of amnesia, particularly when extraordinary means were used to secure the recovery of memory, there is a high probability that the memories are false, i.e. of incidents that had not occurred.<ref>Brandon S ''et al.'' (1998) Recovered memories of childhood sexual abuse. Implications for clinical practice. ''Br J Psychiatry'' 172:296-307. PMID 9722329</ref>
==Amnesia==
Both true and false memories can be recovered using memory work techniques, but there is no evidence that reliable discriminations can be made between them.
[[Amnesia]] is partial or complete loss of memory that goes beyond mere forgetting. Often it is temporary and involves only part of a person's experience. Amnesia is often caused by an injury to the brain, for instance after a blow to the head, and sometimes by psychological trauma. ''Anterograde amnesia'' is a failure to remember new experiences that occur '''after''' damage to the brain; ''retrograde amnesia'' is the loss of memories of events that occurred '''before''' a trauma or injury. For a memory to become permanent (consolidated), there must be a persistent change in the strength of connections between particular neurons in the brain. Anterograde amnesia can occur because this consolidation process is disrupted; retrograde amnesia can result either from damage to the site of memory storage or from a disruption in the mechanisms by which memories can be retrieved from their stores. Many specific types of amnesia are recognised, including:
<ref>Stocks JT (1998) Recovered memory therapy: a dubious practice technique. ''Soc Work'' 43:423-36 PMID 9739631</ref> <ref>Gutheil TG, Simon RI (1997) Clinically based risk management principles for recovered memory cases. ''Psychiatr Serv'' 48:1403-7 PMID 9355166 ''("Controversy over cases involving so-called recovered memories of sexual abuse has threatened to divide the mental health field, ... The authors review issues in this controversy, including the role of misdirected advocacy for recovered memory by some practitioners, the distinction between the actual events and patient's narrative truth as a factor in the therapeutic alliance, and the contrast between therapeutic and legal remedies.")''</ref> Memories elicited under [[hypnotism]] are particularly likely to be false.<ref>Kihlstrom JF (1997) Hypnosis, memory and amnesia. Philos Trans R Soc Lond B Biol Sci 29:3521727-32. PMID 9415925 ''("Hypnotized subjects respond to suggestions from the hypnotist for imaginative experiences involving alterations in perception and memory. ... Hypnotic hypermnesia refers to improved memory for past events. However, such improvements are illusory: hypermnesia suggestions increase false recollection, as well as subjects' confidence in both true and false memories. Hypnotic age regression can be subjectively compelling, but does not involve the ablation of adult memory, or the reinstatement of childlike modes of mental functioning, or the revivification of memory. The clinical and forensic use of hypermnesia and age regression to enhance memory in patients, victims and witnesses (e.g. recovered memory therapy for child sexual abuse) should be discouraged.")''</ref>
 
*''Infantile (childhood) amnesia'', the normal inability to recall events from early childhood. There are various theories about this; some believe that language development is important for efficient storage of long term memories, some believe that early memories do not persist because the brain is still developing.  
 
*''Hysterical amnesia'' (''dissociative Fugue'' or ''fugue amnesia''), a rare condition linked to severe psychological trauma. It is characterised by epidode(s) of "an inability to recall some or all of one's past and either the loss of one's identity or the formation of a new identity occur with sudden, unexpected, purposeful travel away from home." Usually, the memory returns within a few days, although memory of the trauma may remain incomplete.
 
The form of amnesia that is linked with recovered memories is ''dissociative amnesia'' (formerly known as ''psychogenic amnesia''). This results from a psychological cause, not by direct damage to the brain, and is a loss of memory of significant personal information, usually about traumatic or extremely stressful events. Usually this is seen as a gap or gaps in recall for aspects of someone's life history, but with severe acute trauma, such as during wartime, there can be a sudden acute onset of symptoms <ref>[http://books.google.co.uk/books?id=3SQrtpnHb9MC&dq=Diagnostic+and+Statistical+Manual+of+Mental+Disorders,&printsec=frontcover&source=bn&hl=en&ei=yq3MSd7vAcPRjAf2y7XTCQ&sa=X&oi=book_result&resnum=4&ct=result#PPA520,M1 Diagnostic and Statistical Manual of Mental Disorders]</ref>
==Authenticity==
Our memories ''can'' be accurate, but are not ''always'' accurate. For example, eyewitness testimony even of relatively recent dramatic events is notoriously unreliable. <ref>Gonsalves B, Paller KA (2002) Mistaken memories: remembering events that never happened. Neuroscientist 8:391-5. PMID 12374423</ref> Misremembering results from confusion between memories for perceived and imagined events, which may result from overlap between particular features of the stored information comprising memories for perceived and imagined events. Our memories are always a mix of factual traces of sensory information overlaid with emotions, mingled with interpretation and "filled in" with imaginings. Thus there is always skepticism about how valid a memory is as evidence of factual detail. Some believe that accurate memories of traumatic events are often repressed, but remain in the subconscious mind, from where they can be recovered by appropriate therapy. Others believe that truly traumatic events are never forgotten in this way, although often people may not disclose their memories to others. This is a difficult area to study, and unambiguous conclusions are hard to draw. In one study where victims of documented child abuse were reinterviewed many years later as adults, a high proportion of the women denied any memory of the abuse.<ref>{{cite journal |author=Williams LM  |title=Recall of childhood trauma: a prospective study of women's memories of  child sexual abuse |journal=J Consult Clin Psychol |volume=62  |pages=1167–76  |year=1994 |pmid=7860814 |doi=
|url=http://www.hss.caltech.edu/courses/2004-05/winter/psy130/Debate2Williams1.pdf}}</ref>  
 
Those who doubt the existence of "traumatic amnesia" note that various manipulations can be used to implant false memories (sometimes called "pseudomemories"). These can be compelling for those who develop them, and can include details that make them credible to others.<ref>Laney C, Loftus EF (2005) Traumatic memories are not necessarily accurate memories. ''Can J Psychiatry'' 50:823-8. PMID 16483115
</ref> A classic experiment in memory research, conducted by Elizabeth Loftus, became widely known as "Lost in the Mall"; in this, subjects were given a booklet containing three accounts of real childhood events written by family members and a fourth account of a wholly fictitious event of being lost in a shopping mall. A quarter of the subjects reported remembering the fictitious event, and elaborated on it with extensive circumstantial detail.<ref> See Loftus E (1997) Creating false memories ''Scientific American'' 227 no 3 for a popular account</ref> This experiment inspired many others, and in one of these, Porter ''et al.''  could convince about half of his subjects that they had survived a vicious animal attack in childhood.<ref>Porter S ''et al.''(1999) The nature of real, implanted, and fabricated memories for emotional childhood events: implications for the recovered memory debate. ''Law Hum Behav'' 23:517-37 PMID 10487147</ref>


==Neurological Basis of Memory==
While such studies have been criticized <ref name=Crook>{{cite journal |last=Crook |first=L |year=1999 |title=Lost in a shopping mall--A breach of professional ethics. |journal=Ethics Behavior |volume=9  |pages=39–50 |url=http://users.owt.com/crook/memory/ |accessdate= |quote=|doi=10.1207/s15327019eb0901_3}}</ref> in particular about whether the findings are really relevant to trauma memories and psychotherapeutic situations.<ref name=Pope>{{cite journal |last=Pope |first=K |year=1996 |title=Memory, abuse, and science: questioning claims about the false memory syndrome epidemic |journal= Am Psychologist|volume=51|doi=10.1037/0003-066X.51.9.957 |pages=957 }}</ref>, they prompted public and professional concern about [[recovered memory therapy]] for past sexual abuse. When memories are 'recovered' after long periods of amnesia, particularly when extraordinary means were used to secure the recovery of memory, it is now widely (but not universally) accepted that the memories are quite likely to be false, i.e. of incidents that had not occurred.<ref>Brandon S ''et al.'' (1998) Recovered memories of childhood sexual abuse. Implications for clinical practice ''Br J Psychiatry'' 172:296-307. PMID 9722329</ref> It is thus recognised by professional organizations that a risk of implanting false memories is associated with some types of therapy. The ''American Psychiatric Association'' advises that "...most leaders in the field agree that although it is a rare occurrence, a memory of early childhood abuse that has been forgotten can be remembered later. However, these leaders also agree that it is possible to construct convincing pseudomemories for events that never occurred. The mechanism(s) by which both of these phenomena happen are not well understood and, at this point it is impossible, without other corroborative evidence, to distinguish a true memory from a false one." <ref>[http://www.apa.org/topics/memories.html Questions and Answers about Memories of Childhood Abuse] ''American Psychiatric Association''</ref> <ref> Sheflin and Brown state that a total of 25 studies on amnesia for child sexual abuse exist and that they demonstrate amnesia in their study subpopulations. {{cite journal | last = Sheflin | first = AW | coauthors = Brown D |date=1996 | title = Repressed memory or dissociative amnesia: what the science says | journal = J Psychiat Law | volume = 24  | pages = 143–88 | issn = 0093-1853 =}}. An editorial in the ''British Medical Journal'' however, prefaces mention of the Sheflin and Brown study with "on critical examination, the scientific evidence for repression crumbles."{{citation
The neuropsychologist and theoretical neuroscientist [[Donald Hebb]] (1904 - 1985) was the first to distinguish between [[short-term memory]] and [[long-term memory]]. When the brain receives a sensory input, for example, visual and auditory stimuli, a ''sensory memory'' retains an exact copy of what is seen or heard, but this memory lasts for at most only a few seconds. What is retained longer than this depends on [[selective attention]] - things that we "notice" may be stored in short-term memory for up to a few minutes. This memory is thought to depend on electrical activity in neuronal circuits, and is very easily destroyed by interruption or interference. Short term memory includes [[iconic memory]], to hold visual images; [[acoustic memory]], to hold sounds; and [[working memory]], an active process to keep a memory until it is put to use.  
| journal = British Medical Journal (BMJ) | issue= 7130 | volume=316
  | date = 14 February 1998
| title = Editorial &mdash; Recovered memories of childhood sexual abuse: The Royal College of Psychiatrists issues important precautions
| title = Harrison G Pope
| url = http://www.bmj.com/archive/7130/7130e2.htm}}</ref>


Memories stored for longer than this are stored in ''long-term memory''. Hebb's main contribution to neuroscience was his theory that the basis of long-term memory was a form of [[synaptic plasticity]] - a long term alteration in the strength of connections between [[neuron]]s now thought to involve a phenomenon called "[[long-term potentiation]]" (LTP). This is relatively permanent storage, and it requires the synthesis of new proteins.  
Obviously, not all therapists agree that false memories are a major risk with psychotherapy.
<ref name=Hammond>{{cite book |author=Hammond DC; Brown DP.; Scheflin AW |title=Memory, trauma treatment, and the law |publisher=W.W. Norton |location=New York |year=1998 |pages= |isbn=0-393-70254-5 |oclc= |doi= |url=http://books.google.com/books?id=m6P7HAAACAAJ}}</ref>
<ref name=Chu>{{cite journal |last=Chu |first=JA  |coauthors=''et al.''|year=1999  |title=Memories of childhood abuse: Dissociation, amnesia and corroboration.  |journal=Am J Psychiatry |volume=156 |pages=749-55 |accessdate=  |url=http://ajp.psychiatryonline.org/cgi/content/full/156/5/749 |}}</ref> <ref>{{Cite book  |  last = Whitfield MD | first = CL | title = Memory and Abuse -  Remembering and Healing the Effects of Trauma | place= Deerfield Beach, FL |  publisher = Health Communications Inc  |  url=http://books.google.com/books?id=z1LW3u1e04YC | isbn =  1-55874-320-0 ||}}</ref> <ref name=Dalenberg>Dalenberg C (2006) Recovered memory and the Daubert criteria: recovered memory as professionally tested, peer reviewed, and accepted in the relevant scientific community. ''Trauma Violence Abuse'' 7:274-310. PMID 17065548</ref> Several studies have reported high percentages of the corroboration of recovered memories.<ref>{{cite journal |last=Kluft |first=RP  |coauthors= |year=1995  |title=The confirmation and disconfirmation of memories of abuse in Dissociative Identity Disorder patients: A naturalistic study  |journal=Dissociation |volume=8  |pages=253-8  |url=https://scholarsbank.uoregon.edu/xmlui/bitstream/handle/1794/1155/Dis_8_4_9_ocr.pdf?sequence=1 |}}</ref><ref name=Van1995>{{citation  | last1 = van der Kolk |  first1 = BA  | last2 = Fisler | first2 = R  | year = 1995  | title =  Dissociation and the fragmentary nature of traumatic memories: Overview and  exploratory study  | journal = J Traumatic Stress  | volume = 8  | pages =  505–25 |quote= | url  =http://www.psych.utoronto.ca/~peterson/psy430s2001/Van%20der%20Kolk%20Fragmentary%20Nature%20of%20Traumatic%20Memory%20J%20Traumatic%20Stress%201995.pdf}} </ref>, and some authors have claimed that the 'false memory movement' has tended to conceal or ignore evidence of corroboration of recovered memories.<ref>{{cite journal |last=Cheit |first= RE |year= 1998 |month= |title=  Consider this, skeptics of recovered memory |journal= Ethics Behav |volume= 8 |pages= 141–60  |doi= 10.1207/s15327019eb0802_4 |url= http://www.leaonline.com/doi/abs/10.1207/s15327019eb0802_4?journalCode=eb}}</ref> Herman, in her theory of recovery from chronic Post-Traumatic Stress Disorder writes that one of the major recovery stages is the remembering and mourning of the repressed material of traumatic events.<ref>{{cite book  | last = Herman    | first =JL| authorlink =    | coauthors =    | title =Trauma and recovery    | publisher =Basic Books    | date =1997    | location =New York  | pages =290    | url =http://books.google.com/books?id=3cn2R0KenN0C    | doi =    | id =      | isbn =0-465-08730-2 |quote=The ordinary response to atrocities is to banish them from consciousness.}}</ref>


Whether information is stored in long-term memory depends on its 'importance'; for any animal, memories associated with stress or trauma are potentially important for the adaptive value that such memories have for future avoidance behaviour, and the hormones that are released during stress are thought to have an important role in determining what memories are preserved. In humans, acute traumatic stress is associated with acute secretion of [[epinephrine]] and [[norepinephrine]] (adrenaline and noradrenaline) from the [[adrenal medulla]] and more prolonged secretion of [[cortisol]] from the [[adrenal cortex]]. Acute increases in these hormones are thought to facilitate memory while chronic stress associated with prolonged hypersecretion of cortisol may have the opposite effect. The [[limbic system]], including the [[hippocampus]] and [[amygdala]] in particular, is critically involved in memory storage and retrieval as well as giving emotional significance to sensory inputs.The [[hippocampus]] is important for [[explicit memory]], and for [[memory consolidation]]; it is also very sensitive to stress and has a role in recording the emotions of a stressful event. The hippocampus receives input from many different parts of the [[neocortex]] and sends its output out to different parts of the brain. The [[amygdala]], may assign emotional values to sensory inputs which are then elaborated upon by the [[neocortex]] and imbued with personal meaning. It may also integrate internal representations of the external world in memory image form associating emotional experiences with these memories. The septo-hippocampal system is thought to record memory in temporal and spatial dimensions, and plays an important role in storing and categorizing incoming stimuli in memory.
Both true and false 'memories' can be recovered using [[memory work techniques]], but there is no evidence that reliable discriminations can be made between them. <ref>Stocks JT (1998) Recovered memory therapy: a dubious practice technique. ''Soc Work'' 43:423-36 PMID 9739631</ref> Some believe that memories "recovered" under [[hypnotism]] are particularly likely to be false. <ref>Kihlstrom JF (1997) Hypnosis, memory and amnesia. ''Philos Trans R Soc Lond B Biol Sci'' 29:3521727-32 PMID 9415925 </ref>
According to The Council on Scientific Affairs for the ''American Medical Association'', recollections obtained during hypnosis can involve confabulations and pseudomemories and appear to be less reliable than nonhypnotic recall. <ref> (1985) Scientific status of refreshing recollection by the use of hypnosis ''JAMA'' 253: 1918-23 PMID 3974082</ref>


==Amnesia==
==Medico-Legal issues==
[[Amnesia]] involves losses in explicit memory. It is shown by one’s inability to remember personal memories or discuss them verbally, or it may be shown by one’s inability to fully retain in conscious awareness temporarily retrieved memories. Amnesia is often considered to be a dissociative condition, such as dissociative amnesia. An individual may only remember parts of the event, or certain categories about the event (like feelings). Amnesia caused by deficits while encoding information may not be reversible, because the information was not encoded.
Serious issues arise when recovered but false memories result in public allegations; false complaints carry serious consequences for the accused. Many of those who make false claims sincerely believe the truth of what they report. A special type of false allegation, the false memory syndrome, arises typically within therapy, when people report the 'recovery' of childhood memories of previously unknown abuse. The influence of practitioners' beliefs and practices in the eliciting of false 'memories' and of false complaints has come under particular criticism.<ref>Boakes J (1999) False complaints of sexual assault: recovered memories of childhood sexual abuse ''Med Sci Law'' 39:112-20 PMID 10332158 </ref>
Sometimes these memories are used as evidence in criminal prosecutions.  


According to the ''defects in sequential processing'' theory, for a memory to become permanent, there needs to be a structural change in the brain. Amnesia is assumed to occur when the consolidation process is disrupted and either the memory trace doesn’t produce a structural change and gets lost or there is a structural change and access to the memory trace is lost. The ''multiple memory systems'' theories state that amnesia occurs due to a problem in one of the memory systems. These theories assume that the impairment of a psychological system may cause deficits in some kinds of memories but not others. However, none of these models can explain all aspects of amnesia. <ref name=Kolb>{{cite book   | last =Kolb | first =B    | authorlink =  | coauthors = Whishaw I | title =Fundamentals of human neuropsychology (4th ed.). | publisher =W.H. Freeman    | date =1995    | location =New York    | isbn = }}</ref>
It is generally accepted that people sometimes are unable to recall traumatic experiences. The current version (DSM-IV) of the ''Diagnostic and Statistical Manual of Mental Disorders'', published by the ''American Psychiatric Association'', states that "Dissociative amnesia is characterized by an inability to recall important personal information, usually of a traumatic or stressful nature, that is too extensive to be explained by ordinary forgetfulness."<ref>Section 300.12:[http://psych.org/MainMenu/Research/DSMIV.aspx DSM-IV] Diagnostic and Statistical Manual, American Psychiatric Association
</ref>
The term "recovered memory", however, is not listed in DSM-IV or used by any mainstream formal psychotherapy modality.<ref name=Whitfield>{{cite book|title=Misinformation Concerning Child Sexual Abuse and Adult Survivors |last= Whitfield |first=Charles L. |coauthors=Joyanna L. Silberg, Paul Jay Fink |pages=56 |publisher=Haworth Press |year=2001 |isbn= 0789019019}}
</ref>  


==Effects of trauma on memory==
Alan Scheflin, a law professor, explains that this satisfies courts that recovered memories are admissible into evidence in court. "Both those who argue that repressed memories are always false and those who argue that repressed memories are always true [...] appear to be mistaken. Although the science is limited on this issue, the only three relevant studies conclude that repressed memories are no more and no less accurate than continuous memories....”<ref>{{citation  | last = Scheflin | first = A  | year = 1999  | title = Ground lost: the false memory/recovered memory therapy debate  | journal = Psychiatric Times  | volume = 16 | url =http://www.psychiatrictimes.com/display/article/10168/1158280}}
Patients with amygdalar damage are no more likely to remember emotionally charged words than nonemotionally charged ones.
</ref>
A U.S. District Court accepted repressed memories as admissible evidence in a specific case.<ref>“The Validity of Recovered Memory: Decision of a US District Court” Judge Edward F. Harrington, Presentation by Jim Hopper Ph.D. The legal documentation citation is: 923 Federal Supplement 286 (D. Mass. 1996), United States District Court - District of Massachusetts Ann Shahzade, plaintiff Civil Action No.: V. 92-12139-EFH George Gregory, Defendant. [http://www.jimhopper.com/memory-decision/]</ref> Dalenberg argues that the evidence shows that recovered memory cases should be allowed to be prosecuted in court<ref name=Dalenberg/>.
The apparent willingness of courts to credit the recovered memories of complainants but not the absence of memories by defendents has been commented on "It seems apparent that the courts need better guidelines around the issue of dissociative amnesia in both populations."<ref>{{citation | author =Porter S ''et al.'' | date = 2001 | title = Memory for murder. A psychological perspective on dissociative amnesia in legal contexts | journal = Int J Law Psychiatry | volume = 24 | pages = 23-42 | PMID=11346990 }}</ref>


Brain imaging studies suggest that trauma is associated with limbic system abnormalities. Hippocampal damage is connected to over responsiveness to external stimuli. When stress interferes with the hippocampus’ mediation of memory, it is possible that some of the memory is kept by a system that records emotional experience, but there is no symbolic placement of it in time or space. In animals, high stimulation of the amygdala interferes with hippocampal processing. Strong affect may disallow proper evaluating and categorizing of an experience.<ref name=Vander1994/>
==Neurological Basis of Memory==
Traumatic memories are retrieved, at least at first, in the form of mental imprints that are dissociated. These imprints are of the affective and sensory elements of the traumatic experience. Clients have reported the slow emergence of a personal narrative that can be considered explicit (conscious) memory. The emotional significance of a memory correlates with its veracity; memories of highly significant events are usually accurate and stable over time. While people appear to easily assimilate expected and known experiences, aspects of traumatic experiences appear to get stuck in the mind, unaltered by time passing or experiences that may follow. The imprints of traumatic experiences appear to be qualitatively different from those of nontraumatic events. Explicit memories of personal facts or events are affected by lesions of the front lobe and hippocampus. These parts of the brain are also involved in [[PTSD]] neurobiology. Traumatic memories may be coded differently than ordinary event memories, possibly because of alterations in attentional focusing or the fact that extreme emotional arousal interferes with the memory functions of the hippocampus.<ref name=Van1995>{{citation  |
The neuroscientist [[Donald Hebb]] (1904 - 1985) was the first to distinguish between [[short-term memory]] and [[long-term memory]]. According to current theories in neuroscience, things that we "notice" are stored in short-term memory for up to a few minutes; this memory depends on 'reverberating' electrical activity in neuronal circuits, and is very easily destroyed by interruption or interference. Memories stored for longer than this are stored in ''long-term memory''. Whether information is put into this long-term store depends on its 'importance'; memories of traumatic events are important for avoiding similar events in the future, and [[hormones]] that are released during stress have a role in determining what memories are preserved. In humans, traumatic stress is associated with secretion of [[epinephrine]] and [[norepinephrine]] (adrenaline and noradrenaline) from the [[adrenal medulla]] and [[cortisol]] from the [[adrenal cortex]]. In the brain, the [[limbic system]] is a set of interconnected regions, including the [[hippocampus]] and [[amygdala]], which are involved in memory storage and retrieval and in assigning emotional significance to sensory inputs, and cortisol has powerful actions at these sites.<ref>Zola SM (1998) Memory, amnesia, and the issue of recovered memory: neurobiological aspects. ''Clin Psychol Rev'' 18:915-32 PMID 9885767 </ref>
last1 = Van Der Kolk | first1 = BA  | last2 = Fisler | first2 = R
| year = 1995  | title = Dissociation and the fragmentary nature of traumatic memories: Overview and exploratory study  | journal = J Traumatic Stress  | volume = 8  | pages = 505–25  | url =
http://www.psych.utoronto.ca/~peterson/psy430s2001/Van%20der%20Kolk%20Fragmentary%20Nature%20of%20Traumatic%20Memory%20J%20Traumatic%20Stress%201995.pdf
|quote= a systematic exploratory study of 46 subjects with PTSD which indicates that traumatic memories are retrieved, at least initially, in the form of dissociated mental imprints of sensory and affective elements of the traumatic experience: as visual, olfactory, affective, auditory and kinesthetic experiences. Over time, subjects reported the gradual emergence of a personal narrative that can be properly referred to as "explicit memory".}}</ref>


Traumas can interfere with several memory functions. van der Kolk divided these functional disturbances into four sets, traumatic amnesia, global memory impairment, dissociative processes and traumatic memories’ sensorimotor organization. [[Traumatic amnesia]] involves the loss of remembering traumatic experiences. The younger the subject and the longer the traumatic event is, the greater the chance of significant amnesia. Global memory impairment makes it difficult for these subjects to construct an accurate account of their present and past history. Dissociation refers to memories being stored as fragments and not as unitary wholes. Not being able to integrate traumatic memories seems to be the main element which leads to PTSD. In the sensorimotor organization of traumatic memories, sensations are fragmented into different sensory components.<ref name=Van1995/>
Although memory distortion occurs in everyday life, the brain mechanisms involved are not easy to study in the laboratory, but [[neuroimaging]] techniques have recently been applied to this subject. In particular, there have  been studies of ''false recognition'', where individuals incorrectly claim to have encountered a novel object or event, and the results suggest that the hippocampus and several cortical regions may contribute to such false recognition, while the prefrontal cortex may be involved in retrieval monitoring that can limit the rate of false recognition.<ref>Schacter DL, Slotnick SD (2004) The cognitive neuroscience of memory distortion ''Neuron''44:149-60 PMID 15450167</ref>


van der Kolk and Fisler’s study of 46 adults supports [[Piaget]]’s notion that, when memories can’t be integrated linguistically or semantically, they are organized in a more primitive manner as somatic sensations or visual images. In a  neuroimaging study, it was found that when subjects had flashbacks in the laboratory, there was increased activity in the right hemisphere in areas connected to the processing of emotional experiences and in the right visual association cortex. [[Broca’s area]]s in the left hemisphere showed significantly decreased activity. van der Kolk and Fisler’s hypothesis is that under extreme stress, the memory categorization system based in the hippocampus fails, allowing these memories to be kept as emotional and sensory states. Excessive arousal at the moment of trauma interferes with the clear memory processing of the event, leaving unaltered memory traces. When these traces are remembered and put into a personal narrative, they are subject to being condensed, contaminated and embellished upon. When traces are recalled, increased activity in the amygdala might cause the personal assignment of accuracy and individual significance.<ref name=Van1995/>


In van der Kolk’s work on the [[psychobiology]] of PTSD, he states that trauma responses are bimodal. The response to trauma is hyperamnesia, over reaction to stimuli and reexperiencing the trauma, which exists with numbing, avoidance and amnesia. When compensating for chronic hyperarousal, behaviorally subjects with PTSD may shut down and avoid stimuli similar to the trauma. Psychobiologically, they may emotionally numb both to trauma and everyday experience. PTSD subjects may go directly from stimuli to response without an adequate appraisal of the situation, due to their overgeneralization of incoming stimuli, creating flight or fight reactions.<ref name=Vander1994>{{citation  | last = BA  | year = 1994 | title = The Body Keeps the Score: Memory and the Evolving Psychobiology of Posttraumatic Stress | journal = Harvard Rev Psychiat | volume = 1 | pages =253–65 | doi = 10.3109/10673229409017088  | url =http://homepage.psy.utexas.edu/Homepage/Class/Psy394U/Bower/03%20Emot,%20Trauma,Mem/Body%20keeps%20the%20score.%20Kolk%20.pdf |quote=For more than a century, ever since people's responses to overwhelming experiences were first systematically explored, it has been noted that the psychological effects of trauma are expressed as changes in the biological stress response.}}</ref>
==Effects of trauma on memory==
'Betrayal Trauma Theory' proposes that in childhood abuse, dissociative amnesia is an adaptive response; “victims may need to remain unaware of the trauma not to reduce suffering but rather to promote survival.”<ref>{{cite journal  | last = Freyd| first =  J| year = 1994| title = Betrayal trauma: Traumatic amnesia as an adaptive response to childhood abuse  | journal = Ethics Behav| volume = 4
| pages = 307–29| url =http://www.questia.com/read/95814385}}</ref>
When stress interferes with memory, it is possible that some of the memory is kept by a system that records emotional experience, but there is no symbolic placement of it in time or space.<ref name=Vander1994>{{citation  | last = van der Kolk |first=Bessel| year = 1994| title = The body keeps the score: memory and the evolving psychobiology of posttraumatic stress| journal = Harvard Rev Psychiat | volume = 1| pages =253–65| doi = 10.3109/10673229409017088  | url=http://homepage.psy.utexas.edu/Homepage/Class/Psy394U/Bower/03%20Emot,%20Trauma,Mem/Body%20keeps%20the%20score.%20Kolk%20.pdf|}}</ref>
Traumatic memories are retrieved, at least at first, in the form of dissociated mental imprints of the affective and sensory elements of the traumatic experience. Clients have reported the slow emergence of a personal narrative that can be considered explicit (conscious) memory.  


Abnormal physiological responses in PTSD have been shown in two ways. One is due to reminders of the trauma. The second is due to intense, neutral stimuli, such as loud sounds. Individuals with PTSD show several autonomic responses to these stimuli, like blood pressure, skin conductance and heart rate. These highly elevated responses show the timelessness and intensity of how traumatic memories may affect one’s present experience. Lang proposed that emotional memories are stored as associative networks, which are activated when a person gets confronted by a sufficient number of elements that make up these networks. Kolb proposed that excessive stimulation of the CNS during trauma could cause permanent neuronal changes, with a detrimental effect on stimulus discrimination, habituation and learning.<ref name=Vander1994/>
Psychiatrist Bessel van der Kolk <ref name=Van1995/> divided the efffects of traumas on memory functions into:
*[[traumatic amnesia]]; this involves the loss of memories of traumatic experiences. The younger the subject and the longer the traumatic event is, the greater the chance of significant amnesia. Subsequent retrieval of memories after traumatic amnesia is well documented, with examples following natural disasters and accidents, in combat soldiers, in victims of kidnapping, torture and concentration camp experiences, in victims of physical and sexual abuse, and in people who have committed murder.
*[[global memory impairment]]; this makes it difficult for subjects to construct an accurate account of their present and past history. "The combination of lack of autobiographical memory, continued dissociation and of meaning schemes that include victimization, helplessness and betrayal, is likely to make these individuals vulnerable to suggestion and to the construction of explanations for their trauma-related affects that may bear little relationship to the actual realities of their lives"
*[[dissociative processes]]; this refers to memories being stored as fragments and not as unitary wholes.
*traumatic memories’ [[sensorimotor organization]]. Not being able to integrate traumatic memories seems to be linked to ''post traumatic stress disorder'' (PTSD).  <ref>Diagnostic symptoms of PTSD include reexperience such as flashbacks and nightmares, difficulty falling or staying asleep, feelings of panic or fear, depression, headache, and physiological symptoms including irregular heartbeat and diarrhoea.[http://www.rcpsych.ac.uk/mentalhealthinfoforall/problems/posttraumaticstressdisorder/posttraumaticstressdisorder.aspx  Post Traumatic Stress Disorder (PTSD)] The Royal College of Psychiatrists</ref>


Abnormal acoustic startle response (ASR) has been a main feature in trauma response for more than 50 years.  Abnormalities in habituation are found in ASR with PTSD subjects. This failure of habituation for PTSD to loud sounds suggests problems with evaluating sensory input. The fact that PTSD subjects are unable to properly
According to van der Kolk, memories of highly significant events are usually accurate and stable over time; aspects of traumatic experiences appear to get stuck in the mind, unaltered by time passing or experiences that may follow. The imprints of traumatic experiences appear to be different from those of nontraumatic events, perhaps because of alterations in attentional focusing or the fact that extreme emotional arousal interferes with  memory.<ref name=Van1995/> van der Kolk and Fisler’s hypothesis is that under extreme stress, the memory categorization system based in the hippocampus fails, but these memories to be kept as emotional and sensory states.  When these traces are remembered and put into a personal narrative, they may be condensed, contaminated and embellished upon. 
integrate trauma memories is shown physiologically by their misinterpretation of nonthreatening stimuli.<ref name=Vander1994/>


PTSD develops following intense stressors. Intense stress causes the release of stress hormones, like cortisol, norepinephrine, epinephrine, etc. Constant exposure to stress changes an organism’s adaptiveness and how it deals with its daily environment. Studies have shown neuroendocrine abnormalities in PTSD subjects. These studies have shown chronically increased activity of the sympathetic nervous system activity in PTSD. Putnam’s work shows large neuroendocrine changes in sexually abused girls when they are compared to normals.<ref name=Vander1994/>
When there is inadequate recovery time between stressful situations, alterations may occur to the [[stress-response system]], some of which may be irreversible, and cause pathological responses, which may memory loss, learning deficits and other maladaptive symptoms. In animal studies, high levels of [[cortisol]] can cause hippocampal damage, which may cause short-term memory deficits; in humans, MRI studies have shown reduced hippocampal volumes in combat veterans with PTSD, adults with posttraumatic symptoms and survivors of repeated childhood sexual or physical abuse. Trauma may also interfere with implicit memory, where periods of avoidance may be interrupted by intrusive emotional occurrences with no story to guide them. A difficult issue is whether those presumably abused accurately recall their experiences. <ref name=Bremner2002>{{Cite book| last = Bremner| first =  JD| year = 2002| title = Does Stress Damage the Brain? Understanding Trauma-Related Disorders from a Neurological Perspective |publisher=W.W. Norton and Company |location=New York}}</ref>


[[Trauma]] victims do not respond to stress the way normals do. Pressure situations may cause a feeling of retraumatization. High states of arousal may promote the retrieval of trauma memories and associated phenomena such as sensory information or behaviors connected to prior trauma. Therefore, traumatic memories may be considered state dependent. Under stress, people secrete endogenous stress hormones that affect memory consolidation strength. Through studies on animal models, it is assumed that the large secretion of neurohormones during a traumatic event in part causes LTP and the over-consolidation of traumatic memories. This LTP may cause an
==Professional Organisations==
organism to remember a trauma whenever aroused. Reliving the traumatic event may cause stress hormones to strength the memory trace causing a positive feedback loop.<ref name=Vander1994/>
The ''Working Group on Investigation of Memories of Child Abuse'' of the American Psychological Association presented findings mirroring those of the other professional organizations (see External Links subpage for references to various statements made independently by these organisations). The Working Group made five key conclusions:


van der Kolk theorizes that there is a difference between traumatic and nontraumatic memory storage and retrieval. The body’s need to respond in danger situations can be strong. There is a tremendous physiological and neurochemical cost to this type of response, due to the depletion of hormones and neurotransmitters. With adequate recovery time, the body can return to its own homeostasis. When there is inadequate recovery time between stressful situations, alterations may occur to the neurophysiological parts of one’s stress-response system. Some of these alterations may be irreversible. One’s body’s memory and learning systems may be altered affecting implicit and explicit memory. This may cause maladaptive or pathological responses. This damage may cause memory loss, learning deficits and other maladaptive symptoms. Children’s neurological and physiological systems are very vulnerable to the negative impact of trauma. Highly resilient people may have a better chance of experiencing a trauma without developing PTSD. But if a trauma is strong enough, no person is immune to the consequences of developing PTSD. Uncontrollable stress may have a similar impact biologically. It may be possible to look at an individual’s pre and post trauma neurochemistry and tell if they have experienced trauma, but it would not be possible to say what kind of trauma. Animal studies show that [[learned helplessness]] can develop from repeated exposure to inescapable trauma. In humans, physical paralysis is a main feature connected to a traumatic event. This paralysis is connected to hyperamnesia, amnesia and dissociation. Traumatic events may be unavailable to recall or may be recalled only in pieces.<ref name=Knopp1996>{{cite book |last= Knopp |first= Fay Honey |title= A Primer on the Complexities of Traumatic Memory of Childhood Sexual Abuse - A Psychobiological Approach |year= 1996 |publisher= Safer Society Press |location= Brandon, VT |isbn= 1-884444-20-2}}</ref>
(1) Controversies regarding adult recollections should not be allowed to obscure the fact that child sexual abuse is a complex and pervasive problem in America that has historically gone unacknowledged;


Gaps in autobiographical memory are normal to PTSD sufferers, as are problems with nonstressful short-term memory tasks. The successful coding
(2) Most people who were sexually abused as children remember all or part of what happened to them;
of memories entails alert focused awareness when the input is presented. Memory consolidation is most successful when the experience can be elaborated on in conscious thought. A lack of conscious awareness may hurt these processes. Extreme elevations of norepinephrine released in trauma situations are related to the strong implicit hyperamnesia memories and to the explicit deficits of memory of amnesia. Medium to high levels of norepinephrine cause the amygdala to promote LTP in the hippocampus, which may result in vivid memories. Very high levels of norepinephrine and heavy stimulation of the amygdala connected to extreme, prolonged or repeated stress appear to interfere with hippocampal functioning. This interference may hurt cognitive assessment and the encoding of the input.<ref name=Knopp1996/>


Changes in the hippocampus’ functioning during uncontrollable stress may hurt and limit the consolidation of the input into the explicit memory system. Some mental representations of the input may remain in cortical emotional memory, which may cause phobias and anxiety. This explains how trauma sufferers may have amnesia for specific events, but not the emotions connected to them. Excessive levels of opioids released in the brain during trauma and the numbing response connected to them may also be a major factor for the impairment of memory. According to van der Kolk, in animal studies, memory is damaged when a situation can no longer be helped by the animal’s activity. Panic and freeze responses may be seen as defensive ways to allow an organism to not consciously experience overwhelming stress or to not remember an occurrence of overwhelming stress. The second is by changing one’s interpretation of detachment. These events are characteristic of dissociative responses. These influences may cause memories that are unrelated to or dissociated from the normal methods of explicit memory retrieval.<ref name=Knopp1996/>
(3) It is possible for memories of abuse that have been forgotten for a long time to be remembered;


Chronic dopamine dysregulation may be a consequence of trauma. Dopamine’s relationship to working memory in the prefrontal cortex may also show its connection to problems of encoding and short term memory. High levels of cortisol (as mentioned previously by Kalat) may cause memory deficits because of its neurotoxic effects on the hippocampus. In animal studies, high levels of cortisol have been shown to cause hippocampal damage. In humans, MRI studies have shown reduced hippocampal volumes in combat veterans with PTSD, adults with posttraumatic symptoms and survivors of repeated childhood sexual or physical abuse. Hippocampal damage may cause short-term memory retention deficits. van der Kolk writes that PTSD’s essence is memory disturbances. Janet wrote that certain occurrences may leave intense memories in a person. With dissociative trauma survivors, trauma may also interfere with implicit memory, where periods of avoidance may be interrupted by intrusive emotional occurrences with no story to guide them.<ref name=Knopp1996/>
(4) It is also possible to construct convincing pseudo-memories for events that never occurred; and


Bremner cites several studies showing a connection between hippocampal volume and stress related disorders.  Researchers have measured hippocampal volume with MRI; hippocampal volume was reduced in Vietnam combat veterans with PTSD, and in patients with PTSD related to early childhood sexual and physical abuse.  Abuse and PTSD are related to a broad range of memory disturbances, and PTSD sufferers may be more susceptible to memory problems than normals. A difficult issue for Bremner is whether those presumably abused accurately recall their information. <ref name=Bremner2002>{{Cite book  | last = Bremner | first =  JD  | year = 2002  | title = Does Stress Damage the Brain? Understanding Trauma-Related Disorders from a Neurological Perspective |publisher=W.W. Norton and Company |location=New York}}</ref>
(5) There are gaps in our knowledge about the processes that lead to accurate and inaccurate recollections of childhood abuse. <ref>Colangelo JJ (2007)
[http://findarticles.com/p/articles/mi_hb1416/is_2_29/ai_n29342485 Recovered memory debate revisited: practice implications for mental health counselors.(PRACTICE)]Journal of Mental Health Counseling</ref>


==References==
==References==
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Recovered memory is the apparent resurrection of the memory of events that had been forgotten or suppressed for a long time. Retrograde amnesia after physical or emotional trauma (i.e., traumatic amnesia), or the suppression of painful memories from any cause, is well known. However the mechanisms that lead to recovery of long forgotten memories are not well understood, and the authenticity of these recovered memories has often been challenged; in some cases recovered memories are fictitious, although in other cases they may be authentic.[1] [2]

The issues surrounding recovered, or false memories have sparked one of the greatest controversies in the mental health profession of recent times.[3] Some researchers have proposed that memories of extreme trauma are buried in the subconscious by a special process, and are later reliably recovered. Others consider that genuinely traumatic events are seldom truly forgotten, and that the scientific evidence indicates that traumatic amnesia is a myth.[4] [5] However, traumatized individuals exhibit a range of memory impairments, and research on children's and adults' encoding and memory of trauma stimuli has provided some support for models of repression and traumatic amnesia.[6]

Amnesia

Amnesia is partial or complete loss of memory that goes beyond mere forgetting. Often it is temporary and involves only part of a person's experience. Amnesia is often caused by an injury to the brain, for instance after a blow to the head, and sometimes by psychological trauma. Anterograde amnesia is a failure to remember new experiences that occur after damage to the brain; retrograde amnesia is the loss of memories of events that occurred before a trauma or injury. For a memory to become permanent (consolidated), there must be a persistent change in the strength of connections between particular neurons in the brain. Anterograde amnesia can occur because this consolidation process is disrupted; retrograde amnesia can result either from damage to the site of memory storage or from a disruption in the mechanisms by which memories can be retrieved from their stores. Many specific types of amnesia are recognised, including:

  • Infantile (childhood) amnesia, the normal inability to recall events from early childhood. There are various theories about this; some believe that language development is important for efficient storage of long term memories, some believe that early memories do not persist because the brain is still developing.
  • Hysterical amnesia (dissociative Fugue or fugue amnesia), a rare condition linked to severe psychological trauma. It is characterised by epidode(s) of "an inability to recall some or all of one's past and either the loss of one's identity or the formation of a new identity occur with sudden, unexpected, purposeful travel away from home." Usually, the memory returns within a few days, although memory of the trauma may remain incomplete.

The form of amnesia that is linked with recovered memories is dissociative amnesia (formerly known as psychogenic amnesia). This results from a psychological cause, not by direct damage to the brain, and is a loss of memory of significant personal information, usually about traumatic or extremely stressful events. Usually this is seen as a gap or gaps in recall for aspects of someone's life history, but with severe acute trauma, such as during wartime, there can be a sudden acute onset of symptoms [7]

Authenticity

Our memories can be accurate, but are not always accurate. For example, eyewitness testimony even of relatively recent dramatic events is notoriously unreliable. [8] Misremembering results from confusion between memories for perceived and imagined events, which may result from overlap between particular features of the stored information comprising memories for perceived and imagined events. Our memories are always a mix of factual traces of sensory information overlaid with emotions, mingled with interpretation and "filled in" with imaginings. Thus there is always skepticism about how valid a memory is as evidence of factual detail. Some believe that accurate memories of traumatic events are often repressed, but remain in the subconscious mind, from where they can be recovered by appropriate therapy. Others believe that truly traumatic events are never forgotten in this way, although often people may not disclose their memories to others. This is a difficult area to study, and unambiguous conclusions are hard to draw. In one study where victims of documented child abuse were reinterviewed many years later as adults, a high proportion of the women denied any memory of the abuse.[9]

Those who doubt the existence of "traumatic amnesia" note that various manipulations can be used to implant false memories (sometimes called "pseudomemories"). These can be compelling for those who develop them, and can include details that make them credible to others.[10] A classic experiment in memory research, conducted by Elizabeth Loftus, became widely known as "Lost in the Mall"; in this, subjects were given a booklet containing three accounts of real childhood events written by family members and a fourth account of a wholly fictitious event of being lost in a shopping mall. A quarter of the subjects reported remembering the fictitious event, and elaborated on it with extensive circumstantial detail.[11] This experiment inspired many others, and in one of these, Porter et al. could convince about half of his subjects that they had survived a vicious animal attack in childhood.[12]

While such studies have been criticized [13] in particular about whether the findings are really relevant to trauma memories and psychotherapeutic situations.[14], they prompted public and professional concern about recovered memory therapy for past sexual abuse. When memories are 'recovered' after long periods of amnesia, particularly when extraordinary means were used to secure the recovery of memory, it is now widely (but not universally) accepted that the memories are quite likely to be false, i.e. of incidents that had not occurred.[15] It is thus recognised by professional organizations that a risk of implanting false memories is associated with some types of therapy. The American Psychiatric Association advises that "...most leaders in the field agree that although it is a rare occurrence, a memory of early childhood abuse that has been forgotten can be remembered later. However, these leaders also agree that it is possible to construct convincing pseudomemories for events that never occurred. The mechanism(s) by which both of these phenomena happen are not well understood and, at this point it is impossible, without other corroborative evidence, to distinguish a true memory from a false one." [16] [17]

Obviously, not all therapists agree that false memories are a major risk with psychotherapy. [18] [19] [20] [21] Several studies have reported high percentages of the corroboration of recovered memories.[22][23], and some authors have claimed that the 'false memory movement' has tended to conceal or ignore evidence of corroboration of recovered memories.[24] Herman, in her theory of recovery from chronic Post-Traumatic Stress Disorder writes that one of the major recovery stages is the remembering and mourning of the repressed material of traumatic events.[25]

Both true and false 'memories' can be recovered using memory work techniques, but there is no evidence that reliable discriminations can be made between them. [26] Some believe that memories "recovered" under hypnotism are particularly likely to be false. [27] According to The Council on Scientific Affairs for the American Medical Association, recollections obtained during hypnosis can involve confabulations and pseudomemories and appear to be less reliable than nonhypnotic recall. [28]

Medico-Legal issues

Serious issues arise when recovered but false memories result in public allegations; false complaints carry serious consequences for the accused. Many of those who make false claims sincerely believe the truth of what they report. A special type of false allegation, the false memory syndrome, arises typically within therapy, when people report the 'recovery' of childhood memories of previously unknown abuse. The influence of practitioners' beliefs and practices in the eliciting of false 'memories' and of false complaints has come under particular criticism.[29] Sometimes these memories are used as evidence in criminal prosecutions.

It is generally accepted that people sometimes are unable to recall traumatic experiences. The current version (DSM-IV) of the Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychiatric Association, states that "Dissociative amnesia is characterized by an inability to recall important personal information, usually of a traumatic or stressful nature, that is too extensive to be explained by ordinary forgetfulness."[30] The term "recovered memory", however, is not listed in DSM-IV or used by any mainstream formal psychotherapy modality.[31]

Alan Scheflin, a law professor, explains that this satisfies courts that recovered memories are admissible into evidence in court. "Both those who argue that repressed memories are always false and those who argue that repressed memories are always true [...] appear to be mistaken. Although the science is limited on this issue, the only three relevant studies conclude that repressed memories are no more and no less accurate than continuous memories....”[32] A U.S. District Court accepted repressed memories as admissible evidence in a specific case.[33] Dalenberg argues that the evidence shows that recovered memory cases should be allowed to be prosecuted in court[21]. The apparent willingness of courts to credit the recovered memories of complainants but not the absence of memories by defendents has been commented on "It seems apparent that the courts need better guidelines around the issue of dissociative amnesia in both populations."[34]

Neurological Basis of Memory

The neuroscientist Donald Hebb (1904 - 1985) was the first to distinguish between short-term memory and long-term memory. According to current theories in neuroscience, things that we "notice" are stored in short-term memory for up to a few minutes; this memory depends on 'reverberating' electrical activity in neuronal circuits, and is very easily destroyed by interruption or interference. Memories stored for longer than this are stored in long-term memory. Whether information is put into this long-term store depends on its 'importance'; memories of traumatic events are important for avoiding similar events in the future, and hormones that are released during stress have a role in determining what memories are preserved. In humans, traumatic stress is associated with secretion of epinephrine and norepinephrine (adrenaline and noradrenaline) from the adrenal medulla and cortisol from the adrenal cortex. In the brain, the limbic system is a set of interconnected regions, including the hippocampus and amygdala, which are involved in memory storage and retrieval and in assigning emotional significance to sensory inputs, and cortisol has powerful actions at these sites.[35]

Although memory distortion occurs in everyday life, the brain mechanisms involved are not easy to study in the laboratory, but neuroimaging techniques have recently been applied to this subject. In particular, there have been studies of false recognition, where individuals incorrectly claim to have encountered a novel object or event, and the results suggest that the hippocampus and several cortical regions may contribute to such false recognition, while the prefrontal cortex may be involved in retrieval monitoring that can limit the rate of false recognition.[36]


Effects of trauma on memory

'Betrayal Trauma Theory' proposes that in childhood abuse, dissociative amnesia is an adaptive response; “victims may need to remain unaware of the trauma not to reduce suffering but rather to promote survival.”[37] When stress interferes with memory, it is possible that some of the memory is kept by a system that records emotional experience, but there is no symbolic placement of it in time or space.[38] Traumatic memories are retrieved, at least at first, in the form of dissociated mental imprints of the affective and sensory elements of the traumatic experience. Clients have reported the slow emergence of a personal narrative that can be considered explicit (conscious) memory.

Psychiatrist Bessel van der Kolk [23] divided the efffects of traumas on memory functions into:

  • traumatic amnesia; this involves the loss of memories of traumatic experiences. The younger the subject and the longer the traumatic event is, the greater the chance of significant amnesia. Subsequent retrieval of memories after traumatic amnesia is well documented, with examples following natural disasters and accidents, in combat soldiers, in victims of kidnapping, torture and concentration camp experiences, in victims of physical and sexual abuse, and in people who have committed murder.
  • global memory impairment; this makes it difficult for subjects to construct an accurate account of their present and past history. "The combination of lack of autobiographical memory, continued dissociation and of meaning schemes that include victimization, helplessness and betrayal, is likely to make these individuals vulnerable to suggestion and to the construction of explanations for their trauma-related affects that may bear little relationship to the actual realities of their lives"
  • dissociative processes; this refers to memories being stored as fragments and not as unitary wholes.
  • traumatic memories’ sensorimotor organization. Not being able to integrate traumatic memories seems to be linked to post traumatic stress disorder (PTSD). [39]

According to van der Kolk, memories of highly significant events are usually accurate and stable over time; aspects of traumatic experiences appear to get stuck in the mind, unaltered by time passing or experiences that may follow. The imprints of traumatic experiences appear to be different from those of nontraumatic events, perhaps because of alterations in attentional focusing or the fact that extreme emotional arousal interferes with memory.[23] van der Kolk and Fisler’s hypothesis is that under extreme stress, the memory categorization system based in the hippocampus fails, but these memories to be kept as emotional and sensory states. When these traces are remembered and put into a personal narrative, they may be condensed, contaminated and embellished upon.

When there is inadequate recovery time between stressful situations, alterations may occur to the stress-response system, some of which may be irreversible, and cause pathological responses, which may memory loss, learning deficits and other maladaptive symptoms. In animal studies, high levels of cortisol can cause hippocampal damage, which may cause short-term memory deficits; in humans, MRI studies have shown reduced hippocampal volumes in combat veterans with PTSD, adults with posttraumatic symptoms and survivors of repeated childhood sexual or physical abuse. Trauma may also interfere with implicit memory, where periods of avoidance may be interrupted by intrusive emotional occurrences with no story to guide them. A difficult issue is whether those presumably abused accurately recall their experiences. [40]

Professional Organisations

The Working Group on Investigation of Memories of Child Abuse of the American Psychological Association presented findings mirroring those of the other professional organizations (see External Links subpage for references to various statements made independently by these organisations). The Working Group made five key conclusions:

(1) Controversies regarding adult recollections should not be allowed to obscure the fact that child sexual abuse is a complex and pervasive problem in America that has historically gone unacknowledged;

(2) Most people who were sexually abused as children remember all or part of what happened to them;

(3) It is possible for memories of abuse that have been forgotten for a long time to be remembered;

(4) It is also possible to construct convincing pseudo-memories for events that never occurred; and

(5) There are gaps in our knowledge about the processes that lead to accurate and inaccurate recollections of childhood abuse. [41]

References

  1. ↑ Geraerts E et al. (2009) Cognitive mechanisms underlying recovered-memory experiences of childhood sexual abuse. Psychol Sci 20:92-8 PMID 19037903
  2. ↑ Brewin CR, Andrews B (1998) Recovered memories of trauma: phenomenology and cognitive mechanisms. Clin Psychol Rev 18:949-70. PMID 9885769
  3. ↑ Loftus EF, Davis D (2006) Recovered memories Annu Rev Clin Psychol 2:469-98. PMID 17716079
  4. ↑ Gibbs AA, David AS (2003) Delusion formation and insight in the context of affective disturbance.
  5. ↑ Goodyear-Smith FA et al. (1997) Memory recovery and repression: what is the evidence? Health Care Anal 5:99-111 PMID 10167722
  6. ↑ See Policy Forum in Science (2005) and ensuing correspondence. Freyd JJ et al. (2005) Psychology. The science of child sexual abuse. Science (Policy Forum) 308:501 PMID 15845837 Quote from Kihlstrom JF et al. in response in Science 309:1182-5 PMID 16114120 with authors' reply
  7. ↑ Diagnostic and Statistical Manual of Mental Disorders
  8. ↑ Gonsalves B, Paller KA (2002) Mistaken memories: remembering events that never happened. Neuroscientist 8:391-5. PMID 12374423
  9. ↑ Williams LM (1994). "Recall of childhood trauma: a prospective study of women's memories of child sexual abuse". J Consult Clin Psychol 62: 1167–76. PMID 7860814. [e]
  10. ↑ Laney C, Loftus EF (2005) Traumatic memories are not necessarily accurate memories. Can J Psychiatry 50:823-8. PMID 16483115
  11. ↑ See Loftus E (1997) Creating false memories Scientific American 227 no 3 for a popular account
  12. ↑ Porter S et al.(1999) The nature of real, implanted, and fabricated memories for emotional childhood events: implications for the recovered memory debate. Law Hum Behav 23:517-37 PMID 10487147
  13. ↑ Crook, L (1999). "Lost in a shopping mall--A breach of professional ethics.". Ethics Behavior 9: 39–50. DOI:10.1207/s15327019eb0901_3. Research Blogging.
  14. ↑ Pope, K (1996). "Memory, abuse, and science: questioning claims about the false memory syndrome epidemic". Am Psychologist 51: 957. DOI:10.1037/0003-066X.51.9.957. Research Blogging.
  15. ↑ Brandon S et al. (1998) Recovered memories of childhood sexual abuse. Implications for clinical practice Br J Psychiatry 172:296-307. PMID 9722329
  16. ↑ Questions and Answers about Memories of Childhood Abuse American Psychiatric Association
  17. ↑ Sheflin and Brown state that a total of 25 studies on amnesia for child sexual abuse exist and that they demonstrate amnesia in their study subpopulations. Sheflin, AW; Brown D (1996). "Repressed memory or dissociative amnesia: what the science says". J Psychiat Law 24: 143–88. ISSN = 0093-1853 =. . An editorial in the British Medical Journal however, prefaces mention of the Sheflin and Brown study with "on critical examination, the scientific evidence for repression crumbles.""Harrison G Pope", British Medical Journal (BMJ) 316 (7130), 14 February 1998
  18. ↑ Hammond DC; Brown DP.; Scheflin AW (1998). Memory, trauma treatment, and the law. New York: W.W. Norton. ISBN 0-393-70254-5. 
  19. ↑ Chu, JA; et al. (1999). "Memories of childhood abuse: Dissociation, amnesia and corroboration.". Am J Psychiatry 156: 749-55.
  20. ↑ Whitfield MD, CL. Memory and Abuse - Remembering and Healing the Effects of Trauma. Health Communications Inc. ISBN 1-55874-320-0. 
  21. ↑ 21.0 21.1 Dalenberg C (2006) Recovered memory and the Daubert criteria: recovered memory as professionally tested, peer reviewed, and accepted in the relevant scientific community. Trauma Violence Abuse 7:274-310. PMID 17065548
  22. ↑ Kluft, RP (1995). "The confirmation and disconfirmation of memories of abuse in Dissociative Identity Disorder patients: A naturalistic study". Dissociation 8: 253-8.
  23. ↑ 23.0 23.1 23.2 van der Kolk, BA & R Fisler (1995), "Dissociation and the fragmentary nature of traumatic memories: Overview and exploratory study", J Traumatic Stress 8: 505–25
  24. ↑ Cheit, RE (1998). "Consider this, skeptics of recovered memory". Ethics Behav 8: 141–60. DOI:10.1207/s15327019eb0802_4. Research Blogging.
  25. ↑ Herman, JL (1997). Trauma and recovery. New York: Basic Books, 290. ISBN 0-465-08730-2. “The ordinary response to atrocities is to banish them from consciousness.” 
  26. ↑ Stocks JT (1998) Recovered memory therapy: a dubious practice technique. Soc Work 43:423-36 PMID 9739631
  27. ↑ Kihlstrom JF (1997) Hypnosis, memory and amnesia. Philos Trans R Soc Lond B Biol Sci 29:3521727-32 PMID 9415925
  28. ↑ (1985) Scientific status of refreshing recollection by the use of hypnosis JAMA 253: 1918-23 PMID 3974082
  29. ↑ Boakes J (1999) False complaints of sexual assault: recovered memories of childhood sexual abuse Med Sci Law 39:112-20 PMID 10332158
  30. ↑ Section 300.12:DSM-IV Diagnostic and Statistical Manual, American Psychiatric Association
  31. ↑ Whitfield, Charles L.; Joyanna L. Silberg, Paul Jay Fink (2001). Misinformation Concerning Child Sexual Abuse and Adult Survivors. Haworth Press, 56. ISBN 0789019019. 
  32. ↑ Scheflin, A (1999), "Ground lost: the false memory/recovered memory therapy debate", Psychiatric Times 16
  33. ↑ “The Validity of Recovered Memory: Decision of a US District Court” Judge Edward F. Harrington, Presentation by Jim Hopper Ph.D. The legal documentation citation is: 923 Federal Supplement 286 (D. Mass. 1996), United States District Court - District of Massachusetts Ann Shahzade, plaintiff Civil Action No.: V. 92-12139-EFH George Gregory, Defendant. [1]
  34. ↑ Porter S et al. (2001), "Memory for murder. A psychological perspective on dissociative amnesia in legal contexts", Int J Law Psychiatry 24: 23-42
  35. ↑ Zola SM (1998) Memory, amnesia, and the issue of recovered memory: neurobiological aspects. Clin Psychol Rev 18:915-32 PMID 9885767
  36. ↑ Schacter DL, Slotnick SD (2004) The cognitive neuroscience of memory distortion Neuron44:149-60 PMID 15450167
  37. ↑ Freyd, J (1994). "Betrayal trauma: Traumatic amnesia as an adaptive response to childhood abuse". Ethics Behav 4: 307–29.
  38. ↑ van der Kolk, Bessel (1994), "The body keeps the score: memory and the evolving psychobiology of posttraumatic stress", Harvard Rev Psychiat 1: 253–65, DOI:10.3109/10673229409017088
  39. ↑ Diagnostic symptoms of PTSD include reexperience such as flashbacks and nightmares, difficulty falling or staying asleep, feelings of panic or fear, depression, headache, and physiological symptoms including irregular heartbeat and diarrhoea.Post Traumatic Stress Disorder (PTSD) The Royal College of Psychiatrists
  40. ↑ Bremner, JD (2002). Does Stress Damage the Brain? Understanding Trauma-Related Disorders from a Neurological Perspective. New York: W.W. Norton and Company. 
  41. ↑ Colangelo JJ (2007) Recovered memory debate revisited: practice implications for mental health counselors.(PRACTICE)Journal of Mental Health Counseling
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