Abstract
The psychiatric phenomenology exhibited by a mixed group of patients with focal cortical degeneration (FCD) is described. The diagnosis of FCD was made in the presence of a slowly progressive focal neuropsychological deficit without evidence of infarct or neoplasm. Localized or asymmetric atrophy was present on neuroimaging (CT or MRI) and positron emission tomography demonstrated focal hypometabolism or in those assessed later in the disease an area of maximal hypometabolism which correlated with the neuropsychological deficit. FCD patients exhibited prominent obsessive–compulsive behaviour. Obsessive–compulsive features were often repetitive, stereotyped and bizarre and occurred in association with frontal and left temporal atrophy and hypometabolism and were absent in those with predominant posterior cortical pathology.