What is a common symptom of Cotard's syndrome?

Cotard's syndrome, also known as "walking corpse syndrome," is characterized by the belief that one is dead, does not exist, or has lost bodily functions or organs. A significant symptom of this syndrome is the intense fear of losing one's physical life. This symptom is rooted in delusional beliefs about identity and existence, leading to profound existential feelings of despair. Individuals may express beliefs that they have lost their soul or that they are already dead, which captures the essence of the fear related to physical life.

The other symptoms mentioned in the options do not align with the diagnostic criteria for Cotard's syndrome. Loss of acquired language skills typically relates to neurological conditions such as aphasia and not directly to Cotard's. Spasmodic motor movements could be seen in various movement disorders but are not specific to this syndrome. Similarly, restlessness in legs at night is associated with restless legs syndrome, which is a separate condition and does not correlate with the delusions experienced in Cotard's syndrome. Understanding these distinctions helps clarify why fearing the loss of physical life is a hallmark symptom of this specific psychiatric condition.