Table 1.

The Biopsychosocial Model: Predisposing, Precipitating and Perpetuating Factors for the Development and Maintenance of Motor Functional Neurological Disorders

	Biological	Psychological	Psychosocial
Predisposing Vulnerabilities	Sex – female (except for military/veteran cohorts) Intellectual disability Comorbid neurological conditions Other nervous system vulnerabilities Co-morbid functional somatic disorders (i.e., fibromyalgia, irritable bowel syndrome, other chronic pain disorders) Sensory processing difficulties	Mood and anxiety disorders, PTSD, personality disorders Dissociation Alexithymia Insecure attachment Temperament and maladaptive personality traits (i.e., obsessive-compulsive, neuroticism)	Family functioning Chronic illness in family Traumatic death in family Adverse life experiences Financial status Inadequate social support
Precipitating Factors	Abnormal physiological event(s), such as sleep deprivation, hyperventilation, palpitations Acute physical pain Peripheral limb injury or head trauma Dizziness caused by vestibular event Surgical intervention	Emotional reactions to physical injury or other life events Acute dissociative event Panic attack (including dizziness as part of panic)	Loss of employment or other occupational difficulty Divorce or marital strain Traumatic death of loved one Other relational stress
Perpetuating Factors	Physiological arousal Chronic pain Chronic fatigue Abnormal motor habit formation Deconditioning Other medical/neurological comorbidities limiting treatment participation	Negative expectation bias Negative attentional bias Illness beliefs including perception of symptom irreversibility or attribution to another cause Fear of falling “No pain no gain” philosophy to healing Avoidance of symptom exacerbation Hypervigilance and dissociation Identity linked to rigid concepts around self-control, productivity, self-efficacy	Provider diagnostic uncertainty Social benefits of being ill (often out of awareness) Pending litigation Workmen’s compensation/disability Poor care coordination Poor family buy in/support of diagnosis and treatment plan Employer or patient urgency to return to work

Notes: The above list is not exhaustive but rather is representative of the commonly encountered factors that are relevant to consider in developing a patient-oriented biopsychosocial formulation. A given factor may also cut across categories; for example, alexithymia can be both a predisposing vulnerability and a perpetuating factor. Adapted from Psychosomatics.  59(4). McKee K, Glass S, Adams C, et al. The inpatient assessment and management of motor functional neurological disorders: an interdisciplinary perspective. 358–368, copyright (2018), with permission from Elsevier.²¹