The authors examined the relationship between psychiatric symptoms and the presence of of MR deep white matter lesions (DWMLs) in 28 probable Alzheimer's disease (AD) patients with mild to moderate dementia. The difference in frequency of psychiatric symptoms between patients with and without DWMLs was not statistically significant. However, MR global scores of severity correlated with the presence of ideational disturbances (such as low self-esteem and suicidal ideation). Analysis of specific cerebral regions indicated that the highest correlation occurred in the frontal white matter. Thus, DWMLs are correlated with specific symptoms of depression in AD. Whether DWMLs are etiologically related to these symptoms remains to be determined.