Memory and Dissociation

What's dissociation? How's it related to trauma? How do people remember trauma? Find out here.
Memory and Dissociation

Last update: 10 February, 2023

The emotional activation produced by violent events and distressing situations can have an effect on memory. Sometimes, these memories hurt so much that they make us forget everything, even information that we’ve internalized, such as who we are and what we’re called. In effect, our identities become shattered and we might even cease to be. Indeed, there’s a real link between memory and dissociation.

Dissociative disorders are well-defined mental conditions. They’re associated with a history of interpersonal trauma, often severe and chronic. They’re commonly found in individuals with a history of dysfunctional bonding or attachment with their primary caregivers (parents and guardians).

Dissociation and memory

Dissociative phenomena aren’t necessarily pathological. However, when they are, they present in a characteristic manner. Moreover, they have a tremendous impact on the individual’s quality of life. In effect, their coping capacity becomes reduced. This affects the way they’re able to function. For example, at work, school, interpersonal and romantic relationships, and in other significant areas.

The Mayo Clinic defines dissociative disorders as those that involve disconnection and a lack of continuity between thoughts, memories, environments, actions, and identity. They claim that an individual suffering from dissociative disorders escapes from reality in a non-voluntary and non-functional way.

“Dissociation is a disruption of and/or discontinuity in the normal integration of consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior.” 

-APA, 2013-

It’s important to note that dissociation doesn’t occur on its own. Nor is it voluntary. The World Health Organization (WHO) defines it as “an involuntary interruption, or discontinuity, in the normal integration of one or more of the following aspects: identity, sensations, perceptions, affects, thoughts, memories, control over bodily movements or behavior. The interruption or discontinuity may be complete, but more often it is partial and may vary from day to day and even hour to hour”.

head with thunder
There are certain psychological factors that mediate the relationship between trauma and dissociation.

Van der Hart’s theory of structural dissociation states that dissociation acts as a mechanism for dealing with trauma. Trauma ranges from post-traumatic stress disorder (PTSD) to more serious post-traumatic conditions. For instance, multiple personality disorder or dissociative identity disorder (DID).

“Psychic trauma or psychological trauma is generally an event that profoundly threatens the well-being or life of an individual and the consequence of that event on the mental or emotional structure of the same.”


To dissociate is to separate. According to Van der Hart’s theory, trauma produces a separation between the two essential systems for the functioning of the human being:

  • The defense system. It ensures that, in the face of danger, we generate behavioral responses of fight, flight, or submission. Van der Hart calls this system the Emotional Part of the Personality (EP).
  • The system that’s in charge of the tasks of daily life. For instance, how we relate and bond with others, take care of our children, eat, or have sex. Van der Hart calls this system the Apparently Normal Personality (ANP).

Prolonged stress

When we’re subjected to the prolonged impacts of traumatic situations, both systems separate. They split. They dissociate. The more severe the trauma, the greater the separation. It can give rise to dissociative disorders such as:

  • Dissociative amnesia. The individual is unable to remember important autobiographical information. As a rule, the information they don’t remember is of a traumatic and stressful nature. This isn’t ordinary forgetfulness. It’s the result of a memory defect and dissociation.
  • Dissociative fugue. The individual wanders and ends up in an unexpected place due to memory loss.
  • Depersonalization. The sufferer experiences feelings of unreality, detachment, or being an outside observer regarding their own thoughts, feelings, sensations, body, or actions. For example, perceptual disturbances, a distorted sense of time, unreality, selflessness, or emotional numbing.
  • Derealization. They experience a feeling of distance from their environment. For instance, they perceive objects as unreal, dreamlike, hazy, lifeless, or visually distorted.
  • Multiple personality disorder or dissociative identity disorder. An identity disturbance. The sufferer exhibits two or more well-defined personality states. In some cultures, they’re described as experiences of possession.

“Identity is the set of thoughts, values, memories and contextual elements that constitute the personality, character, way of life and way of acting of an individual. It is a complex construct that provides a consistent image of oneself, and that is constantly being formed in each person, in a continuous process of adaptation to the environment and the culture that surrounds them.”

-González Vázquez-

Fragile memories

When exploring dissociation, we need to take into account the following:

Before diagnosis

At the time of the evaluation, it’s important to detect certain aspects that are essential for a diagnosis to be made. They’re as follows:

  • The individual suffers from total or partial amnesia. The question should be asked as to whether it’s related to their personal history of childhood and adolescence.
  • They suffer from other psychiatric diagnoses (with different symptoms) that have been present over time. For example, psychoses, mood disorders, and personality disorders.
  • Their amnesia occurs in the form of spontaneous conversations or in the context of self-harm (behaviors such as cutting, burning, or hitting themselves).
  • Despite several treatments, their disorder shows no improvement.
  • They suffer from borderline personality disorder with episodes of severe self-harm that don’t improve, despite treatment.
  • Their symptoms appear spontaneously in adulthood after a period of functioning successfully.

Memories and dissociation

There’s no reason to doubt a memory that a patient expresses in a therapy session. However, the therapist should examine it carefully and in an undirected way. In other words, they should analyze without asking the patient questions that have an implicit answer. The therapist must allow the patient to expose their memory as they remember it. After all, memories aren’t usually literal and could be easily modified by the therapist.

As we mentioned earlier, trauma is associated with dissociation, but this isn’t a direct relationship. Indeed, dissociation doesn’t always develop with trauma. Psychological factors of the individual also play a role, such as emotional regulation. Not everyone reacts to the same situation in the same way.

Man doing therapy
The relationship between memory and dissociation is moderated by how we respond to events.

Reliability of eyewitness accounts

You may think that, since traumatic events can have such a great impact on our lives, we’d retain this information more successfully than others. However, science doesn’t yet know if this is the case. In fact, studies are conflicting. What we do know is that trauma information is stored differently from other information.

Studies that have analyzed real-life events suggest that negative events that become trauma are better remembered. They’re more detailed, exact, and persistent in our memories. That said, memories are subject to the same law as all other memories: that of distortion.

This means that the gist of the information remains, but the details change over time. Moreover, there’s no scientific evidence to support the idea that the greater the intensity of the experience, the better the memory of the trauma.

False memories

The only thing that, at present, we can affirm with some certainty is that the more intense the traumatic situation, the better the individual remembers the central and critical details, but not the peripheral ones. It’s for this reason that the therapist must always explore carefully and in an undirected way. It’s so they don’t ‘implant’ false memories in their patient.

“A false memory is one that has all the characteristics of the real memory (belief, images and details), but that does not correspond to any real episode that the person has lived, at least as he remembers it.”


Finally, victims of traumatic situations don’t forget the traumatic events. They remember them a great deal. In fact, they remember them so much it hurts. They especially recall the memories that contain the main events, even though the rest of the information may have deteriorated and become impoverished by the passage of time.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

  • American Psychiatric Association – APA. (2014). Manual diagnóstico y estadístico de los trastornos mentales DSM5 (5a. ed)
  • Belloch, A; Sandín, B; Ramos, F. (2021). Manual de psicopatología. Capítulo trastornos disociativos. McGrow-Hill. McGrow-Hill.
  • Luna, K., & Migueles Seco, M. M. (2007). Memoria de testigos: patrón de distorsión de los recuerdos por la presentación de información falsa.
  • Migueles, M., & García-Bajos, E. (2004). ¡ Esto es un atraco! Sesgos de la tipicidad en la memoria de testigos. Estudios de Psicología25(3), 331-342.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.