Which is a key feature in diagnosing conversion disorder?

The key feature in diagnosing conversion disorder is that the physical examination reveals unremarkable findings. This means that while the patient presents with neurological symptoms such as paralysis, weakness, or seizures, the medical evaluations and diagnostic tests show no anatomical or physiological abnormalities that would account for these symptoms. This lack of pathological findings is crucial in differentiating conversion disorder from other medical or neurological diagnoses.

In conversion disorder, the symptoms are real and can significantly impair functioning, but they cannot be explained by underlying physical illness or injury. This characteristic emphasizes the psychosomatic nature of conversion disorder, where psychological factors manifest as physical symptoms. Understanding this feature helps clinicians identify conversion disorder and guide appropriate treatment strategies that may involve psychological interventions rather than purely medical ones.

The other options involve aspects that are not typically associated with conversion disorder. For instance, the presence of a known neurological disease would suggest an organic cause for the symptoms, and clear evidence of substance abuse issues could imply alternative diagnoses. Additionally, symptoms occurring without prior psychological stress is contrary to the typical presentation of conversion disorder, where psychological factors often precede the onset of physical symptoms.