Dissociative Disorders

Dissociative disorders are mental health conditions where there is a disconnection between thoughts, memories, feelings, surroundings, behaviour or sense of identity. People may feel detached from themselves or the world, experience memory gaps, or feel as if they are watching life from the outside.

Dissociation can be a normal response to stress – for example, “zoning out” on a long drive or losing track of time while absorbed in a task. In dissociative disorders, however, these experiences are more severe, frequent or distressing, and interfere with everyday life.

Dissociative disorders are often linked with trauma, chronic stress, or other mental health conditions. They can also overlap with Functional Neurological Disorder (FND) and dissociative (functional) seizures, which we commonly see within our specialist inpatient neurorehabilitation programmes.

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What Are Dissociative Disorders?

Dissociative disorders sit on a spectrum. At one end are brief, mild episodes that many people experience; at the other are persistent, distressing symptoms that significantly affect identity, memory and functioning.

Common experiences of dissociation include:

• Feeling detached from your body or as though you are watching yourself from the outside (depersonalisation)
• Feeling that the world around you is unreal, foggy or dream-like (derealisation)
• Memory gaps for everyday events or important personal information
• Feeling as if different “parts” of you take over at different times
• Finding yourself in a place with no memory of how you got there

These experiences are not deliberate or “put on”. They are usually automatic responses to overwhelming stress, trauma or conflict, where the mind partially disconnects to cope.

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Types of Dissociative Disorders

Different classification systems describe several dissociative disorders. The main types include:

Depersonalisation / Derealisation Disorder

This condition involves persistent or recurrent:

• Depersonalisation – feeling detached from your own thoughts, feelings or body, as if you are an outside observer
• Derealisation – feeling that the world around you is unreal, distant, “lifeless” or foggy

People usually know that these experiences are not literally true, which can make them even more frightening. Depersonalisation/derealisation can last for moments or many years and is often linked with trauma, severe stress, anxiety or depression.

Dissociative Amnesia (with or without fugue)

Dissociative amnesia involves gaps in memory that cannot be explained by ordinary forgetting, head injury or a medical condition. Typically, the person may be unable to recall:

• Important personal information
• Specific traumatic or stressful events
• Periods of time (hours, days or longer)

Sometimes this is accompanied by a dissociative fugue, where a person may travel or wander away and temporarily lose their usual identity or sense of self.

Dissociative Identity Disorder (DID)

DID is characterised by:

• The presence of two or more distinct identity states or personality states, each with its own pattern of perceiving and relating to the world
• Recurrent gaps in memory for everyday events, personal information or traumatic experiences

DID is strongly associated with severe and often repeated trauma, particularly in childhood. It is a complex and sometimes misunderstood condition, requiring specialist psychological care.

Dissociative Neurological Symptom Disorder / Functional Neurological Disorder (FND)

In ICD-11, functional neurological symptoms are grouped under “dissociative neurological symptom disorder”, reflecting their overlap with dissociative disorders.

This includes functional problems with:

• Movement or weakness
• Sensation (e.g. numbness, visual loss)
• Cognition
• Non-epileptic (dissociative/functional) seizures

Our dedicated pages on Functional Neurological Disorder (FND) cover these symptoms in more detail.

Dissociative (Functional) Seizures – PNES

Dissociative seizures (also called functional or psychogenic non-epileptic seizures – PNES) are episodes that look like epileptic seizures but are not caused by abnormal electrical activity in the brain. They can involve collapse, shaking, unresponsiveness or “blank spells”, and often occur in the context of dissociation and trauma.

ICD-11 explicitly includes “dissociative neurological symptom disorder, with non-epileptic seizures” as a subtype, underlining the link between dissociative mechanisms and functional seizures.

You can read more on our dedicated Dissociative (Non-Epileptic) Seizures page.

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Causes and Risk Factors

Dissociative disorders usually develop as a response to overwhelming stress or trauma, particularly when it occurs repeatedly or at a young age. Common contributing factors include:

• Childhood physical, emotional or sexual abuse
• Neglect or unstable caregiving
• Exposure to domestic violence, war, torture or severe bullying
• Traumatic events in adulthood, such as assault, accidents or disasters
• Ongoing chronic stress, including health-related and interpersonal stressors

Dissociation may initially be a coping strategy – a way for the mind to distance itself from experiences that feel too overwhelming to process. Over time, this pattern can become habitual and intrusive, leading to a dissociative disorder.

Other risk factors include:

• Co-existing mental health conditions (e.g. PTSD, depression, anxiety, personality disorders)
• Neurodevelopmental conditions and a history of self-harm or suicidality
• Physical health problems and functional neurological symptoms, especially dissociative seizures

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Symptoms of Dissociative Disorders

Symptoms vary depending on the type of dissociative disorder, but may include:

Changes in Awareness and Perception

• Feeling detached from your body, as if you are watching yourself from the outside
• Feeling that the world is unreal, distant, foggy or “not quite right”
• Episodes of feeling “spaced out”, disconnected or as though time has slowed or sped up

Memory and Identity Symptoms

• Gaps in memory for everyday events, personal information or traumatic experiences
• Finding possessions, messages or evidence of actions you do not remember
• Feeling that different “parts” of you have different emotions, preferences or behaviours
• Sense of identity confusion or uncertainty about who you are

Emotional and Physical Symptoms

• Numbness or emotional detachment, feeling cut off from feelings
• Sudden shifts in mood or behaviour that feel outside your control
• Physical symptoms such as functional seizures, sensory changes, pain or fatigue, often in the context of FND
• Difficulties in relationships, work or education due to dissociation

Many people with dissociative disorders also experience anxiety, depression, PTSD or self-harm thoughts, which require careful assessment and support.

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Dissociative Disorders, FND and Dissociative Seizures

Dissociation and FND are closely linked:

• ICD-11 groups functional neurological symptoms under dissociative neurological symptom disorders, emphasising shared mechanisms.
• Dissociation has long been proposed as one of the psychological mechanisms underpinning FND, including motor, sensory and seizure-like symptoms.
• Dissociative (functional) seizures sit at the intersection of epilepsy services, FND and dissociative disorders, and are strongly associated with trauma and dissociation.
• Functional Neurological Disorder (FND) – functional limb weakness, gait disorder, sensory changes, functional cognitive symptoms
• Dissociative (Non-Epileptic) Seizures (PNES)
• Complex neurological illness where dissociation and FND overlap with organic disease

Our role is to support people whose dissociative experiences are part of a wider neurorehabilitation need, rather than to act as a standalone specialist trauma or psychotherapy service.

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How Are Dissociative Disorders Diagnosed?

Diagnosis is usually made by a mental health professional (psychiatrist, psychologist or specialist therapist), often in collaboration with neurology or other medical teams where there are neurological or seizure-like symptoms.

Assessment may include:

• A detailed clinical interview exploring dissociative experiences, trauma history, mood and functioning
• Screening tools or structured interviews for dissociation and related conditions
• Neurological assessment and investigations (e.g. EEG, video-EEG, MRI) where seizures or FND symptoms are present, to rule out epilepsy or structural brain disease epilepsybehavior.com+2NCBI+2
• Review of other mental health conditions, substance use and physical health

A dissociative disorder is diagnosed when:

• Dissociative symptoms are persistent, distressing and impair daily life
• Symptoms fit a recognised pattern (e.g. DID, depersonalisation/derealisation disorder, dissociative amnesia)
• Other explanations (such as neurological disease, substance effects) have been appropriately excluded

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Treatment and Management

Treatment for dissociative disorders is usually longer-term and psychotherapeutic, focusing on stabilisation, safety and integration of experiences, rather than quick-fix interventions.

Approaches may include:

Psychological Therapies

• Trauma-focused psychotherapy – to process traumatic memories safely where appropriate
• Phase-based treatment, often starting with:
  • Stabilisation and safety
  • Emotional regulation and coping skills
  • Then, if indicated, gradual trauma processing
• Approaches such as CBT, EMDR, dialectical or other integrative therapies, depending on individual need

Therapy usually aims to:

• Reduce distress from dissociative symptoms
• Improve sense of continuity of self and personal history
• Strengthen grounding, emotional regulation and relationship skills

Medication

There is no specific medication for dissociative disorders themselves, but medicines may be prescribed to help with:

• Co-existing depression, anxiety or PTSD
• Sleep problems or other mental health difficulties

Medication decisions are made by a GP or psychiatrist, as part of an overall treatment plan.

Self-Management and Support

People may also benefit from:

• Psychoeducation about dissociation, trauma and FND
• Grounding techniques, relaxation and skills for staying present
• Support groups or peer communities
• Practical support around housing, work, finances and relationships

Because dissociative disorders can be complex and long-standing, care often involves coordinated support from multiple services.

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When to Seek Urgent Help

This page provides general information and does not replace individual medical or psychiatric assessment.

You should seek urgent help (999, 111 or your local emergency service) if:

• You have thoughts of harming yourself or ending your life
• You feel unable to stay safe due to intense distress, voices, self-harm urges or severe dissociation
• You experience sudden neurological symptoms, such as:
  • New weakness or numbness
  • Sudden speech difficulties
  • Sudden loss of vision
  • A new seizure or collapse

These may indicate a medical or psychiatric emergency and should be assessed immediately.