This study examined etiological factors and symptom triggers of functional motor symptoms (FMS) or functional seizures (FS) and assessed potential relationships with relevant clinical features (i.e., functional symptoms, quality of life, and general functioning).

Seventeen participants with FMS or FS and 17 healthy control participants underwent an in-depth clinical interview and completed questionnaires assessing adverse life events, psychological and physical symptoms, alexithymia, autistic traits, illness perceptions, health-related quality of life (HRQoL), and work and social functioning.

Participants with FMS or FS perceived various causes of the disorder, including physical symptoms (65%), emotional problems (53%), adverse life events (47%), and work-related factors (29%). Triggers of FMS and FS included physical activity or exertion (59%), stress and emotions (59%), sensory experiences (47%), and fatigue (41%). Compared with healthy control participants, participants with FMS or FS reported more adverse events during adolescence and higher levels of alexithymia, somatoform dissociation, psychological dissociation (disengagement, depersonalization, and derealization), anxiety, depression, and physical symptoms. Participants with FMS or FS had worse HRQoL than healthy control participants and impaired work and social functioning. There were inverse associations between HRQoL scores and somatoform dissociation, anxiety, and adverse life events.

Participants with FMS or FS reported diverse biopsychosocial etiological factors and symptom triggers. Ongoing psychological symptoms and lifetime adverse experiences were associated with worse HRQoL. Future studies will examine these factors in larger samples of individuals with FMS or FS to better understand their shared and distinct etiological underpinnings.