Dissociation

Dissociation is a psychological defense mechanism in which an individual disconnects from their thoughts, feelings, memories, or sense of identity. It represents the mind’s attempt to protect itself from overwhelming or traumatic experiences by creating distance between consciousness and painful material.

Types of Dissociation

Depersonalization

Depersonalization involves feeling disconnected from oneself—as if observing oneself from outside the body. The individual may feel detached from their thoughts, emotions, or physical sensations.

Derealization

Derealization involves feeling disconnected from the external world—as if the world is unreal, foggy, or dreamlike. The environment may seem distant, distorted, or unfamiliar.

Dissociative Amnesia

Dissociative amnesia involves gaps in memory, particularly around traumatic events. These memory gaps are different from ordinary forgetting and are typically related to traumatic experiences.

Dissociative Identity

In extreme cases, dissociation can lead to fragmentation of identity, though this is rare and typically occurs only after severe, chronic trauma during early childhood.

Characteristics of Dissociation

• Feeling “spaced out”: A sense of mental fog or disconnection
• Time distortion: Losing track of time or feeling like time is moving strangely
• Emotional numbness: Difficulty feeling emotions or feeling disconnected from them
• Physical detachment: Feeling disconnected from the body or physical sensations
• Identity confusion: Uncertainty about who you are or feeling fragmented
• Memory gaps: Missing periods of time or difficulty recalling events
• Reduced pain awareness: Diminished awareness of physical pain or sensations
• Automatic behaviors: Acting on “autopilot” without conscious awareness

Dissociation and Trauma

Dissociation is strongly associated with trauma, particularly:

• Childhood trauma: Chronic or severe trauma during childhood, when the developing brain is most vulnerable
• Repeated trauma: Ongoing traumatic experiences that make dissociation a habitual response
• Early onset trauma: Trauma occurring during critical developmental periods
• Inescapable trauma: Situations where the individual cannot escape or fight back

Dissociation as a Spectrum

Dissociation is not binary—it exists on a continuum of intensity. The degree of dissociation can vary based on:

• Stress levels: As stress and overwhelm increase, dissociation typically intensifies
• Trauma triggers: Exposure to trauma reminders can increase dissociative responses
• Internal state: Fatigue, illness, or emotional states can affect dissociation levels
• Safety levels: Feeling unsafe can increase dissociation, while feeling safer can reduce it
• Time of day: Some individuals experience more dissociation during certain times or situations

This means that dissociation can range from mild experiences of feeling “spaced out” or disconnected to more severe states involving memory gaps, depersonalization, or derealization. Many trauma survivors experience dissociation in varying degrees throughout the day, depending on their stress levels and environmental factors.

Clinical Understanding

Research supports the understanding of dissociation as existing on a spectrum. Clinical scales like the Dissociative Experiences Scale (DES) measure dissociation across a range from 0-100, recognizing that everyone experiences some degree of dissociation (even mild, like highway hypnosis), but trauma survivors often score higher and experience more frequent and intense dissociative states.

As Briere and Scott (2014) note in Principles of Trauma Therapy, “Dissociation is not an all-or-nothing phenomenon. It exists on a continuum, and the intensity can vary based on internal and external stressors” (p. 142).

Dissociation as a Survival Mechanism

Dissociation serves as a protective mechanism during trauma, allowing the individual to survive overwhelming experiences by:

• Emotional numbing: Reducing or eliminating awareness of painful emotions
• Creating distance: Making traumatic experiences feel less real or immediate
• Conserving resources: Allowing the body to focus on survival rather than processing
• Protecting consciousness: Preventing complete psychological breakdown

Productive Dissociation in Adulthood

While dissociation can be problematic when it interferes with daily functioning, it can also be adaptive in adulthood. The ability to remain calm and emotionally regulated during intense situations—often facilitated by mild to moderate dissociation—can be valuable in high-pressure environments.

Many trauma survivors have developed the capacity to stay calm under extreme pressure, making them effective in crisis situations, emergency services, healthcare, and other high-stress professions. The emotional numbing and ability to create distance from overwhelming situations that dissociation provides can allow individuals to function effectively when others might be overwhelmed.

For example, Marsha Linehan, the developer of Dialectical Behavior Therapy (DBT), has spoken about how her own experience with severe trauma and dissociation in her youth influenced her ability to stay calm and focused in intense situations. Her capacity to remain emotionally regulated during crisis—developed as a survival mechanism—became an asset in her work developing treatments for people in extreme emotional distress.

When Dissociation Serves Adults Well

• Crisis situations: Remaining calm and focused during emergencies
• High-stress professions: Functioning effectively under pressure in demanding careers
• Emotional regulation: Managing intense emotions that might otherwise be overwhelming
• Professional detachment: Maintaining appropriate boundaries in emotionally charged work
• Stress tolerance: Handling situations that others find too stressful

This adaptive use of dissociation demonstrates that the same mechanisms that protected us during trauma can, when harnessed appropriately, become useful skills in adulthood.

When Dissociation Becomes Problematic

While dissociation can be adaptive during trauma, it becomes problematic when it persists beyond the traumatic event, interfering with daily functioning:

• Impaired memory: Difficulty forming or recalling memories, both traumatic and everyday
• Emotional disconnection: Difficulty feeling emotions or connecting with others emotionally
• Disrupted sense of self: Fragmented or unstable sense of identity
• Functional impairment: Difficulty with work, relationships, or daily tasks
• Physical disconnection: Reduced awareness of bodily sensations, pain, or physical needs

Recognition and Treatment

Recognizing dissociation can be challenging because it often operates outside conscious awareness. Common signs include:

• Losing time or having gaps in memory
• Feeling disconnected from self or surroundings
• Difficulty recalling traumatic events
• Emotional numbness or flatness
• Automatic behaviors without conscious control
• Feeling like events happened to someone else

Treatment for dissociation typically involves:

• Somatic approaches: Body-based therapies that help reconnect with physical sensations
• Trauma processing: Carefully paced work to process traumatic memories
• Grounding techniques: Practices to anchor in the present moment
• Safety building: Creating internal and external safety to reduce the need for dissociation
• Integration work: Helping fragmented parts of self come together

Neuroscience of Dissociation

Cortical Disconnection

Dissociation involves decreased connectivity between different regions of the brain, particularly between cortical (conscious) and subcortical (unconscious) structures. This disconnection prevents integration of experience, creating fragmented awareness.

Default Mode Network Alterations

The default mode network (DMN), active during rest and self-referential thought, shows altered activity patterns in individuals who dissociate. There may be decreased connectivity within the DMN, contributing to feelings of disconnection from self.

As Lanius et al. (2010) explain, “Dissociation involves a disruption in the normal integration of consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior” (p. 631).

Right Hemisphere Dominance

Dissociative responses are often associated with right hemisphere processing, which handles implicit memory, emotion, and body awareness. Traumatic experiences processed primarily in the right hemisphere may remain disconnected from left hemisphere language and narrative systems.

Hippocampal Involvement

The hippocampus, crucial for memory formation and contextual processing, may function differently during dissociative states. There may be reduced hippocampal activity during trauma, preventing formation of coherent, integrated memories.

Prefrontal Cortex Deactivation

Dissociation often involves decreased activity in the prefrontal cortex, which is responsible for executive functions, self-awareness, and emotional regulation. This deactivation may allow the individual to disconnect from overwhelming experiences but also impairs integration and processing.

Amygdala-Hippocampus Disconnection

During dissociation, there may be a disconnect between the amygdala (emotional processing) and hippocampus (memory formation). This prevents traumatic experiences from being processed and integrated, leaving them stored in fragmented, implicit form.

The Freeze Response

Dissociation is closely related to the freeze response—the body’s automatic shutdown when fight or flight are not possible. This involves activation of the parasympathetic nervous system’s dorsal vagal complex, leading to immobilization, shutdown, and disconnection.

As Stephen Porges explains in Polyvagal Theory, “Dissociation is the ultimate survival strategy when fight and flight are not options. The body shuts down, conserving energy and creating psychological distance from unbearable experience” (Porges, 2011, p. 258).

Neurochemical Changes

Dissociation involves changes in neurotransmitter systems:

• Opioid system activation: Endogenous opioids released during trauma can produce numbing and disconnection
• NMDA receptor involvement: Glutamate receptors involved in consciousness and memory may function differently during dissociative states
• GABA system changes: Changes in inhibitory neurotransmitter systems may contribute to altered consciousness

Brainstem Modulation

The brainstem, particularly the reticular activating system (RAS), plays a crucial role in consciousness and awareness. During dissociation, brainstem activity may be modulated to reduce awareness and connection to experience.

Memory Systems and Dissociation

Dissociation involves disrupted integration between explicit (conscious) and implicit (unconscious) memory systems:

• Explicit memory: Disrupted formation and retrieval of conscious, narrative memories
• Implicit memory: Traumatic experiences stored as implicit memories without conscious awareness
• Memory fragmentation: Lack of integration between emotional, sensory, and contextual aspects of memory

Neural Oscillations

Brain activity patterns (neural oscillations) may be altered during dissociation. There may be changes in gamma, beta, and alpha wave activity, contributing to altered states of consciousness and awareness.

Structural Brain Changes

Chronic dissociation may be associated with structural changes in the brain, including:

• Corpus callosum: Reduced size or connectivity in the corpus callosum (connecting left and right hemispheres), contributing to fragmented processing
• Hippocampal volume: Reduced hippocampal volume associated with memory disruption
• Prefrontal cortex: Structural changes in prefrontal regions related to executive function and self-awareness

Dissociation Intensity and Neural Connectivity

The varying intensity of dissociation corresponds to degrees of neural disconnection. Research using functional MRI shows that:

• Mild dissociation: May involve slight decreases in connectivity between brain regions
• Moderate dissociation: Involves more significant disconnection between cortical and subcortical structures
• Severe dissociation: Involves substantial disconnection between brain regions, including decreased communication between hemispheres

The degree of neural disconnection corresponds to the intensity of dissociative experience. As stress increases, neural connectivity decreases, leading to more intense dissociative states. This explains why dissociation can feel like a “dimmer switch” rather than an on/off switch—as overwhelm increases, the brain progressively disconnects regions to protect consciousness.

Graded Dissociative Response

The brain has a graded response to threat and overwhelm:

• Low threat: Minimal dissociation, slight emotional numbing
• Moderate threat: Increased dissociation, more significant disconnection
• High threat: Severe dissociation, substantial disconnection from experience
• Extreme threat: Complete dissociation, complete disconnect from consciousness

This graded response allows the brain to calibrate the degree of protection needed based on the level of overwhelm, rather than switching between complete presence and complete dissociation.

References

Briere, J. N., & Scott, C. (2014). Principles of trauma therapy: A guide to symptoms, evaluation, and treatment (2nd ed.). SAGE Publications.

Lanius, R. A., Vermetten, E., Loewenstein, R. J., Brand, B., Schmalzl, L., Bremner, J. D., & Spiegel, D. (2010). Emotion modulation in PTSD: Clinical and neurobiological evidence for a dissociative subtype. American Journal of Psychiatry, 167(6), 640-647. https://doi.org/10.1176/appi.ajp.2009.09081168

Porges, S. W. (2011). The polyvagal theory: Neurophysiological foundations of emotions, attachment, communication, and self-regulation. W. W. Norton & Company.