Fragmentation of memory

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Fragmentation of memory is a memory disorder where an individual is unable to associate the context of the memories to their autobiographical (episodic) memory. While the explicit facts and details of the events may be known to the person (semantic memory), the facts of the events retrieve none of the affective and somatic elements of the experience. Therefore, the emotional and personal content of the memories can't be associated with the rest of the memory. [1] Fragmentation of memory can occur for relatively recent events as well.

Contents

The impaired person usually suffers from physical damage to or underdevelopment of the hippocampus. This may be due to a genetic disorder or be the result of trauma, such as post-traumatic stress disorder. [2] Brain dysfunction often has other related consequences, such as oversensitivity to some stimuli, impulsiveness, lack of direction in life, occasional aggressiveness, a distorted perception of oneself, and impaired ability to empathize with others, which is usually masked.

Definition

Fragmentation of memory is a type of memory disruption pertaining to the flaws or irregularities in sequences of memories, "coherence, and content" in the narrative or story of the event. [3] During a traumatic experience, memories can be encoded irregularly which creates imperfections in the memory. [3] It is also described as a memory that has been jumbled, confused, or repeated unnecessarily. [3]

Causes

Memories of trauma are often fragmented because these memories aren't usually put together properly. Instead, they include intense emotions, sensations, and perceptions. Memories of traumatic events can eventually be constructed into a narrative but usually remain fragmented. [4] In peri-traumatic dissociation, where individuals separate memories from their emotional experiences, there is a "data-driven" processing style and "conceptually driven" processing occurs less. [5] This leads to fragmentation of memory relating to the events of the trauma, meaning that the individual encoded the trauma based on facts of what they saw but they are missing the structure that pieces this together into one synthesized memory. Fragmentation of memory is claimed to happen in posttraumatic stress disorder victims often. During the traumatic event, dissociation occurs and this leads to irregularities in the encoding process. This then leads to lapses in the memory and therefore fragmentation of memory. [3] Therefore, it is important to understand fragmentation of memory in order to treat posttraumatic stress disorder. [3]

Experimentation

Most experiments involving memory fragmentation have been based on empirical studies where individuals were asked to recall memories. These individuals were asked to recall a traumatic event and explain their memories of the event. Their responses were then analysed for "cohesiveness and semantic structure". [6] While experimentation has found results relating to fragmentation of memory, these findings aren't always very clear or conclusive because there are limitations regarding the methods used in experiments. These can be attributed to examples such as the fact that there isn't a definite way to test for posttraumatic stress disorder.

Dissociation and Fragmentation of Memory

Dissociation has been linked to fragmentation of memory. Dissociation of traumatic events is often associated with fragmentation of memory. After a traumatic event, people often dissociate from the experience by separating memories from the emotions involved. [4] In peri-traumatic dissociation, the memory of the trauma is fragmented because of how the information is encoded. It is encoded with mostly a "data-driven" processing style and less of a "conceptually driven" processing style. [5] This means that the data of the surroundings are encoded, such as the details of the individual's surroundings but many of the more complex and conceptual information isn't properly encoded in the memory.

These two terms are commonly used together but it is also stated that a solid review of the findings for this link has not yet been completed. [3]

Fragmentation of memory is common in two dissociative disorders. [7]

Notable cases

See also

Related Research Articles

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Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that develops from experiencing a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on a person's life or well-being. Symptoms may include disturbing thoughts, feelings, or dreams related to the events, mental or physical distress to trauma-related cues, attempts to avoid trauma-related cues, alterations in the way a person thinks and feels, and an increase in the fight-or-flight response. These symptoms last for more than a month after the event. Young children are less likely to show distress, but instead may express their memories through play. A person with PTSD is at a higher risk of suicide and intentional self-harm.

Repressed memory is a controversial, and largely scientifically discredited, psychiatric phenomenon which involves an inability to recall autobiographical information, usually of a traumatic or stressful nature. The concept originated in psychoanalytic theory where repression is understood as a defense mechanism that excludes painful experiences and unacceptable impulses from consciousness. Repressed memory is presently considered largely unsupported by research. Sigmund Freud initially claimed the memories of historical childhood trauma could be repressed, while unconsciously influencing present behavior and emotional responding; he later revised this belief.

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Psychological trauma is an emotional response caused by severe distressing events that are outside the normal range of human experiences, such as experiencing violence, rape, or a terrorist attack. The event must be understood by the affected person as directly threatening the affected person or their loved ones with death, severe bodily injury, or sexual violence; indirect exposure, such as from watching television news, may be extremely distressing and can produce an involuntary and possibly overwhelming physiological stress response, but does not produce trauma per se.

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<span class="mw-page-title-main">Dual representation theory</span>

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References

  1. ↑ van der Kolk, Bessel A.; Fisler, Rita (1995-10-01). "Dissociation and the fragmentary nature of traumatic memories: Overview and exploratory study". Journal of Traumatic Stress. 8 (4): 505–525. doi:10.1007/BF02102887. ISSN   1573-6598.
  2. ↑ Rubin, D. C. (2004). "Reliving, emotions, and fragmentation in the autobiographical memories of veterans diagnosed with PTSD". Applied Cognitive Psychology. 18 (1): 17–35. CiteSeerX   10.1.1.1025.9891 . doi:10.1002/acp.950.
  3. 1 2 3 4 5 6 Bedard-Gilligan, M.; Zoellner, L. A. (2012). "Dissociation and Memory Fragmentation in Posttraumatic Stress Disorder: An Evaluation of the Dissociative Encoding Hypothesis". Memory (Hove, England). 20 (3): 277–299. doi:10.1080/09658211.2012.655747. PMC   3310188 . PMID   22348400.
  4. 1 2 Van Der Hart, O.; Bolt, H.; Van Der Kolk, B. A. (2005). "Memory fragmentation in dissociative identity disorder". Journal of Trauma & Dissociation. 6 (1): 55–70. CiteSeerX   10.1.1.557.6463 . doi:10.1300/J229v06n01_04. PMID   16150685. S2CID   17027735.
  5. 1 2 Kindt, Merel; Van Den Hout, Marcel; Buck, Nicole (2005). "Dissociation related to subjective memory fragmentation and intrusions but not to objective memory disturbances". Journal of Behavior Therapy and Experimental Psychiatry. 36 (1): 43–59. doi:10.1016/j.jbtep.2004.11.005. hdl: 1874/11270 . PMID   15687009.
  6. ↑ Shiromani, Peter; Keane, Terrence; Ledoux, Joseph E. (2009-03-06). Post-Traumatic Stress Disorder: Basic Science and Clinical Practice. ISBN   978-1-60327-329-9.
  7. ↑ Barlow, David H. (2009). Abnormal Psychology: an Integrated Approach. Belmont. CA: Wadsworth Publishing. pp. 191–192.
  8. ↑ Bartram, G. (2008). "Memory, Amnesia and Identity in Hermann Broch's Schlafwandler Trilogy". German Life and Letters. 61 (2): 215–230. doi: 10.1111/j.1468-0483.2008.00420.x .
  9. ↑ Candel, I.; Merckelbach, H.; Kuijpers, M. (2003). "Dissociative experiences are related to commissions in emotional memory". Behaviour Research and Therapy. 41 (6): 719–725. doi:10.1016/s0005-7967(03)00016-0. PMID   12732378.
  10. ↑ van der Hart O, Bolt H, van der Kolk BA (2005). "Memory fragmentation in dissociative identity disorder". J Trauma Dissociation. 6 (1): 55–70. CiteSeerX   10.1.1.557.6463 . doi:10.1300/J229v06n01_04. PMID   16150685. S2CID   17027735.
  11. ↑ José Alejandro Rodríguez; Maykel Espinosa Rodríguez (August 19, 2018). "La historia de la única sobreviviente del accidente aéreo en Cuba" [The story of the only survivor of the aviation accident in Cuba] (in Spanish). Retrieved August 29, 2018.
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