Which nonverbal sign is most consistent with Functional Neurological Symptom Disorder?

• A. Consistent exam findings that map to neuroanatomy
• B. Absence of variability during testing
• C. Inconsistent exam findings, non-anatomical distribution, variability with distraction; la belle indifference
• D. Clear objective signs on imaging

Answer: (C)

Functional Neurological Symptom Disorder shows neurologic symptoms that are real to the patient but not explained by a recognizable neurological disease, and the exam often reveals nonveridical, non-anatomical signs that fluctuate with distraction. The best nonverbal clue is an examination where the signs don’t fit neuroanatomy and vary with attention or testing—sometimes described as inconsistency on exam, non-dermatomal or non-neuroanatomical spread of symptoms, and even a lack of distress about the symptoms (la belle indifference). These patterns distinguish FND from true organic neurologic conditions, which typically produce consistent, anatomically coherent findings and may be supported by objective imaging.