[Non-persistent "doll phenomenon" in a patient with right thalamic infarction]

An 81-year-old right-handed woman was admitted because of acute dysarthria and left hemiparesis. She had lived herself without aids until the admission. On neurological examination she was confused and disoriented. She was ambulant, but had mild dysarthria and mild left hemiparesis. Neuropsychological tests showed severe impairment of memory, mild impairment of visual cognition, decreased fluency of word recall and mild paramnesia, but no acalculia, agraphia, aphasia or apraxia. MRI of the brain showed small infarction in the right anterior thalamus. 123I-IMP SPECT demonstrated a decrease in CBF of the thalamus, basal ganglia and frontal lobe on the right. During admission, she always played with a doll as if she took it as a real baby. This peculiar symptom. "doll phenomenon" continued for approximately three months later. The "doll phenomenon" usually appears in demented patients with diffuse mental deterioration or dysfunction of the frontal lobe. The present patient had not been demented until the onset of the thalamic infarction, and disturbance of cognition caused by the right thalamic infarction probably produced the "doll phenomenon".