BACKGROUND: Functional movement disorders (FMD) are associated with a high prevalence of psychiatric comorbidities. OBJECTIVE: To assess the frequency of obsessive-compulsive symptoms (OCS) in FMD. METHODS: A total of 167 consecutive patients with clinically definite FMD (mean age = 44.4 years, standard deviation [SD] = 12.0, 119 females) and 145 healthy controls (mean age = 43.2 years, SD = 11.8, 103 females) completed the Obsessive-Compulsive Inventory-Revised (OCI-R), which is a widely used tool for assessing OCS. The cutoff score ≥21 is indicative of clinically significant obsessive-compulsive disorder (OCD). Motor symptom severity was assessed using the Simplified FMD Rating Scale (S-FMDRS). All subjects completed questionnaires for depression, anxiety, pain, fatigue, cognitive complaints, health-related quality of life, and childhood trauma. Personality traits were assessed using the Big Five questionnaire. RESULTS: FMD patients had higher mean OCI-R score and higher proportion of individuals with OCI-R ≥ 21 42%, 95% confidence interval (CI) = (30.2, 54.6) versus 16%, 95% CI = (8.2, 28.2) in controls, P < 0.001. Patients had higher scores in three domains: checking, ordering, and obsessing (P < 0.001). FMD patients with OCI-R score ≥21 had higher depression, anxiety, cognitive complaints, and lower quality of life compared to those with score <21 (P < 0.001). No correlation between OCI-R and S-FMDRS scores was found. CONCLUSIONS: FMD patients reported higher rates of OCS compared to controls, along with higher rates of non-motor symptoms and lower quality of life. This finding may have clinical implications and raises the possibility of shared risk factors and common pathophysiological mechanisms in FMD and OCD.

• Keywords
• conversion disorder, functional movement disorder, motor functional neurological disorder, obsessive‐compulsive disorder,
• Publication type
• Journal Article MeSH

OBJECTIVE: Our objective was to assess cognitive functioning across multiple cognitive domains using a standardised neuropsychological battery in patients with motor functional neurological disorders (mFND). METHODS: Thirty patients with clinically established mFND and 30 age-, sex- and education-matched control subjects underwent a thorough neuropsychological assessment evaluating (1) attention including processing speed, (2) executive functions including working memory, (3) short-term memory, (4) speech and language and (5) visuospatial functions. Performance validity tests (PVT) and self-report measures of depression, anxiety and cognitive complaints were included in the assessment. Only patients with valid test performance were included in the analysis. RESULTS: Three patients scored below the cut-off scores in PVT. Patients performed significantly worse than controls in the following areas: (1) the attention domain which included a slow processing speed (p = 0.005, Cohen's d = 0.89), (2) executive functions (p = 0.01, Cohen's d = 0.88) and (3) speech and language domains (p = 0.025, Cohen's d = 0.77). Patients with mFND showed greater intra-individual variability in cognitive performance (p = 0.005, Cohen's d = 0.94). Cognitive impairments were independent of depressive symptoms, which were higher in mFND patients. CONCLUSION: This study revealed both subjective and objective cognitive impairment in patients with mFND. The neuropsychological profile in mFND was characterised primarily by attentional impairment including a slow processing speed and a high intra-individual variability in cognitive performance. Cognitive impairment was associated with a valid test performance, highlighting that the deficits observed were not likely to be explained by a lack of effort in the patient group. Attention is considered to play a key role in mFND pathophysiology, and the results suggest that such impairments are objectively measurable.

• Keywords
• Attention, Cognitive functions, Motor functional neurological disorders, Neuropsychological profile, Performance validity,
• MeSH
• Executive Function physiology   MeSH
• Cognition physiology   MeSH
• Cognitive Dysfunction * complications   etiology   MeSH
• Cognition Disorders * diagnosis   etiology   MeSH
• Conversion Disorder * MeSH
• Humans MeSH
• Neuropsychological Tests MeSH
• Attention physiology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH