Dissociative neurological symptom disorder

Essential Features:

• Involuntary disruption or discontinuity in the normal integration of motor, sensory, or cognitive functions, lasting at least several hours.
• Clinical findings are not consistent with a recognized Disease of the Nervous System (e.g., a stroke) or another medical condition (e.g., a head injury).
• The symptoms do not occur exclusively during episodes of Trance Disorder, Possession Trance Disorder, Dissociative Identity Disorder, or Partial Dissociative Identity Disorder.
• The symptoms are not due to the effects of a substance or medication on the central nervous system, including withdrawal effects, do not occur exclusively during hypnagogic or hypnopompic states, and are not due to a Sleep-Wake disorder (e.g., Sleep-Related Rhythmic Movement Disorder, Recurrent isolated sleep paralysis).
• The symptoms are not better accounted for by another mental disorder (e.g., Schizophrenia or Other Primary Psychotic Disorder, Post-Traumatic Stress Disorder).
• The symptoms result in significant impairment in personal, family, social, educational, occupational or other important areas of functioning.

Symptom specifiers:

Specific presenting symptoms in Dissociative Neurological Symptom Disorder may be identified using the following symptom specifiers. Multiple specifiers may be assigned as necessary to describe the clinical presentation.

6B60.0 with visual disturbance

• Characterized by visual symptoms such as blindness, tunnel vision, diplopia, visual distortions or hallucinations that are not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and do not occur exclusively during another Dissociative Disorder.

6B60.1 with auditory disturbance

• Characterized by auditory symptoms such as loss of hearing or auditory hallucinations that are not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and do not occur exclusively during another Dissociative Disorder.

6B60.2 with vertigo or dizziness

• Characterized by a sensation of spinning while stationary (vertigo) or dizziness that is not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and does not occur exclusively during another Dissociative Disorder.

6B60.3 with other sensory disturbance

• Characterized by sensory symptoms not identified in other specific categories in this grouping such as numbness, tightness, tingling, burning, pain, or other symptoms related to touch, smell, taste, balance, proprioception, kinaesthesia, or thermoception. The symptoms are not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and do not occur exclusively during another Dissociative Disorder.

6B60.4 with non-epileptic seizures

• Characterized by a symptomatic presentation of seizures or convulsions that are not consistent with a recognized Disease of the Nervous System, other mental disorder, or another health condition and do not occur exclusively during another Dissociative Disorder.

6B60.5 with speech disturbance

• Characterized by symptoms such as difficulty with speaking (dysphonia), loss of the ability to speak (aphonia) or difficult or unclear articulation of speech (dysarthria) that are not consistent with a recognized Disease of the Nervous System, a Neurodevelopmental or Neurocognitive Disorder, other mental disorder, or another medical condition and do not occur exclusively during another Dissociative Disorder.

6B60.6 with paresis or weakness

• Characterized by a difficulty or inability to intentionally move parts of the body or to coordinate movements that is not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and does not occur exclusively during another Dissociative Disorder.

6B60.7 with gait disturbance

• Characterized by symptoms involving the individual’s ability or manner of walking, including ataxia and the inability to stand unaided, that are not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and do not occur exclusively during another Dissociative Disorder.

6B60.8 with movement disturbance

• Characterized by symptoms such as chorea, myoclonus, tremor, dystonia, facial spasm, parkinsonism, or dyskinesia that are not consistent with a recognized Disease of the Nervous System, other mental disorder, or another medical condition and do not occur exclusively during another Dissociative Disorder.

6B60.9 with cognitive symptoms

• Characterized by impaired cognitive performance in memory, language or other cognitive domains that is internally inconsistent and not consistent with a recognized Disease of the Nervous System, a Neurodevelopmental or Neurocognitive Disorder, other mental disorder, or another medical condition and does not occur exclusively during another Dissociative Disorder.

6B60.Y with other specified symptoms

6B60.Z with unspecified symptoms

Boundary with Normality (Threshold):

• Transient alterations in sensory or cognitive functions that can accompany intense engagement in work or sports or intense emotional states and transient difficulties in coordinating movements (e.g., during situations of intense anxiety) are relatively common and do not result in significant impairment in personal, family, social, educational, occupational or other important areas of functioning. Such transient experiences should not be considered as symptomatic of Dissociative Neurological Symptom Disorder.
• Experiences resembling Dissociative Neurological Symptom Disorder can occur as a part of culturally sanctioned rituals and in some cases can persist for several months (e.g., following a death). If such presentations are not associated with impairment in functioning, a diagnosis of Dissociative Neurological Symptom Disorder should not be assigned. Depending on the nature of the circumstances preceding the onset of symptoms, as well as their duration, Acute Stress Reaction may be considered.

Course Features:

• Onset of Dissociative Neurological Symptom Disorder typically occurs between puberty and early adulthood; although onset in early childhood (as young as age 3) has been observed, it is extremely rare. Onset after age 35 is uncommon.
• The onset of Dissociative Neurological Symptom Disorder is usually acute and the disorder may follow either a transient or a persistent course. Symptoms are typically of brief duration (e.g., remission within 2 weeks) but commonly recur.
• Onset is often associated with a traumatic or adverse life event. Prior physical injury and a history of childhood abuse or neglect are risk factors for Dissociative Neurological Symptom Disorder. In addition, a prior Disease of the Nervous System is a risk factor for the disorder; for example, individuals with a history of epilepsy are more likely to exhibit non-epileptic seizures. Patients may also present with symptoms that closely resemble the symptoms of physical illnesses experienced by their friends or family members.
• Non-epileptic seizures are more likely to have their onset earlier in the lifespan than motor symptoms.
• Positive prognostic factors include younger age, acute onset, onset associated with a clearly identifiable stressor, early diagnosis, monosymptomatic presentation, short duration of symptoms and short interval between symptom onset and initiation of treatment. Patients with good premorbid adjustment, above-average intelligence and those who accept the psychological nature of the disorder also have a better prognosis. Negative prognostic factors include non-transient symptoms, polysymptomatic presentation, the presence of comorbid medical conditions, and co-occurring mental disorders (e.g., Mood Disorders or Anxiety or Fear-Related Disorders). Patients with maladaptive personality traits, history of sexual abuse or poor physical functioning prior to diagnosis also have a poorer prognosis.
• Individuals with symptoms of paralysis, aphonia, blindness or deafness tend to have a better prognosis than those with symptoms of tremor or non-epileptic seizures.

Developmental Presentations:

• Onset of Dissociative Neurological Symptom Disorder in childhood is often associated with minor illness or physical injury.
• Gait disturbances and non-epileptic seizures are the most prominent and the most frequent symptoms of Dissociative Neurological Symptom Disorder in children and adolescents. The range and number of symptoms observed often expands with age and duration of the disorder.
• The most common psychosocial stressors associated with Dissociative Neurological Symptom Disorder in children include bullying or victimization, school-related stressors, family conflict or parental separation, and the death of a relative or friend.
• Individuals with Dissociative Neurological Symptom Disorder often grow up in families that are excessively preoccupied with illness.
• Adolescents with Dissociative Neurological Symptom Disorder frequently have co-occurring Mood Disorders, Anxiety or Fear-Related Disorders, as well as other medical symptoms. Mood and/or Anxiety or Fear-Related Disorders often persist even after remission of the symptoms of Dissociative Neurological Symptom Disorder. Among adolescents, Dissociative Neurological Symptom Disorder is more likely to be transient.

Culture-Related Features:

• Symptoms of Dissociative Neurological Symptom Disorder that are typical in one cultural context may be considered unusual in another, such as localized heat sensations, ‘peppery’ feelings on the skin, and sensations of being touched or pushed. These symptoms may be connected to local expressions of distress that reference cultural explanations of aetiology (e.g., spiritual origins) or pathophysiology (e.g., subtle energies). Alternatively, in some cultures dissociative symptoms may be attributed to an undiagnosed physical illness, such as occurs in Hypochondriasis (Health Anxiety Disorder); response to reassurance may suggest Hypochondriasis rather than a Dissociative Disorder.
• Dissociative seizures and convulsions tend to have higher prevalence in low- and middle-income countries and communities. Variations in prevalence may reflect greater traumatic exposure, sanctions against verbal expressions of disagreement by persons with marginalized status, or cultures in which somatic expressions of distress are more common. Lower prevalence of dissociative symptoms may be related to negative cultural views of such ‘out-of-control’ behaviour.

Sex- and/or Gender-Related Features:

• Dissociative Neurological Symptom Disorder is two to three times more frequently diagnosed in females, who also have a younger age of onset.
• In men, Dissociative Neurological Symptom Disorder is associated with a history of industrial, military or other occupational accident. In women, symptoms are more often linked to stress caused by family or other interpersonal interactions.

Boundaries with Other Disorders and Conditions (Differential Diagnosis):

• Boundary with Dissociative Amnesia: Dissociative Amnesia involves memory deficits that are manifested as an inability to recall important autobiographical memories, typically of recent traumatic or stressful events. The memory deficits are inconsistent with ordinary forgetting and are not due to the direct effects of a substance or a Disease of the Nervous System. If cognitive symptoms are narrowly focused on autobiographical memory, Dissociative Amnesia is the more appropriate diagnosis. Cognitive symptoms presented in Dissociative Neurological Symptom Disorder involve other cognitive phenomena.
• Boundary with other Dissociative Disorders: Dissociative motor, sensory, or cognitive symptoms are commonly a part of the clinical presentation of Trance Disorder, Possession Trance Disorder, Dissociative Identity Disorder, or Partial Dissociative Identity Disorder. A separate diagnosis of Dissociative Neurological Symptom Disorder should not be assigned if the symptoms occur exclusively during symptomatic episodes of another Dissociative Disorder.
• Boundary with Factitious Disorder and Malingering: In Dissociative Neurological Symptom Disorder, despite the presented symptoms (e.g., seizures, paralysis) not being consistent with neurological findings or other pathophysiology, the symptoms are not feigned, falsified or intentionally induced as in Factitious Disorder or Malingering.
• Boundary with other mental disorders: Somatic symptoms that are not consistent with an identified medical condition also occur in Bodily Distress Disorder, and a variety of somatic symptoms may also occur in Schizophrenia or Other Primary Psychotic Disorders, Mood Disorders, Anxiety or Fear-Related Disorders, Obsessive-Compulsive or Related Disorders, and Disorders Specifically Associated with Stress. Dissociative Neurological Symptom Disorder should not be diagnosed if the symptoms are accounted for by another mental disorder.
• Boundary with Diseases of the Nervous System and other medical conditions classified elsewhere: The diagnosis of Dissociative Neurological Symptom Disorder requires a medical evaluation to rule out Diseases of the Nervous System and other medical conditions as the cause of the presenting motor, sensory, or cognitive symptoms. In Dissociative Neurological Symptom Disorder, clinical and laboratory findings are inconsistent with recognized symptoms of Diseases of the Nervous System or other medical conditions as indicated by an alternative examination method (e.g., normal simultaneous electroencephalogram(EEG) during an apparent seizure or convulsion).