Aetiological Factors in Functional Seizures and Functional Motor Symptoms: Shared and Distinct Features

TY - JOUR

T1 - Aetiological Factors in Functional Seizures and Functional Motor Symptoms

T2 - Shared and Distinct Features

AU - Millman, L S Merritt

AU - Bhuma, Snigdha

AU - Basamh, Yasmine

AU - Uloyok-Job, Jemima

AU - Davies, Jessica

AU - Blunstone, Lauren

AU - Manoharan, Akshaana

AU - Coebergh, Jan

AU - David, Anthony S.

AU - Edwards, Mark

AU - Goldstein, Laura

AU - Hodsoll, John

AU - Mehta, Mitul

AU - Nicholson, Timothy

AU - Stanton, Biba R.

AU - Winston, Joel

AU - Chalder, Trudie

AU - Hotopf, Matthew

AU - Pick, Susannah

PY - 2026/4/12

Y1 - 2026/4/12

N2 - Background: Functional seizures (FS) and functional motor symptoms (FMS), subtypes of functional neurological disorder, may involve shared and distinct predisposing, precipitating, perpetuating, and triggering (PPPT) factors. This study investigated potential self-reported PPPT factors in FS and FMS separately. Methods: Two hundred participants (FS=50, FMS=50, individuals with anxiety and/or depression [CC]=50, healthy controls [HC]=50) completed an in-depth medical history interview and online questionnaires to assess potential aetiological factors including traumatic/adverse life events, alexithymia, autistic traits, psychological and physical symptoms, illness perceptions, cognitive-behavioural responses, and outcome measures of general functioning, and health-related quality-of-life (HRQoL). Results: Participants with FS more frequently reported traumatic/adverse events and psychopathology (e.g., dissociation, PTSD) as possible illness causes/precipitating factors, and sensory symptom triggers, relative to FMS and/or CCs. In contrast, participants with FMS endorsed physical illness causes/precipitating factors, and physical activity and emotion-related symptom triggers, more frequently than FS and/or CCs. Physical and dissociative symptoms were elevated, alongside reductions in HRQoL and general functioning, in FS/FMS compared to CCs/HCs. Greater current, threatening illness-related beliefs/cognitions were disclosed in FS/FMS compared to CCs. Negative associations between HRQoL, cognitive-behavioural responses, and traumatic/adverse events were also seen in FS/FMS. Conclusions: Traumatic events and psychopathology may be more prominently involved in the development/maintenance of FS, and physical illness/injury, physical functioning, and alexithymia may be more central to FMS. Unhelpful illness-related beliefs, and impacts on HRQoL and general functioning, are shared between these subtypes. The results of this study provide insight into potential unique and overlapping characteristics of FS/FMS, with implications for treatment.

AB - Background: Functional seizures (FS) and functional motor symptoms (FMS), subtypes of functional neurological disorder, may involve shared and distinct predisposing, precipitating, perpetuating, and triggering (PPPT) factors. This study investigated potential self-reported PPPT factors in FS and FMS separately. Methods: Two hundred participants (FS=50, FMS=50, individuals with anxiety and/or depression [CC]=50, healthy controls [HC]=50) completed an in-depth medical history interview and online questionnaires to assess potential aetiological factors including traumatic/adverse life events, alexithymia, autistic traits, psychological and physical symptoms, illness perceptions, cognitive-behavioural responses, and outcome measures of general functioning, and health-related quality-of-life (HRQoL). Results: Participants with FS more frequently reported traumatic/adverse events and psychopathology (e.g., dissociation, PTSD) as possible illness causes/precipitating factors, and sensory symptom triggers, relative to FMS and/or CCs. In contrast, participants with FMS endorsed physical illness causes/precipitating factors, and physical activity and emotion-related symptom triggers, more frequently than FS and/or CCs. Physical and dissociative symptoms were elevated, alongside reductions in HRQoL and general functioning, in FS/FMS compared to CCs/HCs. Greater current, threatening illness-related beliefs/cognitions were disclosed in FS/FMS compared to CCs. Negative associations between HRQoL, cognitive-behavioural responses, and traumatic/adverse events were also seen in FS/FMS. Conclusions: Traumatic events and psychopathology may be more prominently involved in the development/maintenance of FS, and physical illness/injury, physical functioning, and alexithymia may be more central to FMS. Unhelpful illness-related beliefs, and impacts on HRQoL and general functioning, are shared between these subtypes. The results of this study provide insight into potential unique and overlapping characteristics of FS/FMS, with implications for treatment.

KW - Functional Neurological Disorder

KW - Neuropsychiatry

KW - Psychiatry

KW - Quality of life

KW - functional seizures

KW - functional motor symptoms

KW - Aetiology

M3 - Article

SN - 0022-3050

JO - Journal of Neurology, Neurosurgery and Psychiatry

JF - Journal of Neurology, Neurosurgery and Psychiatry

ER -