Is the finding of obsessional behaviour relevant to the differental diagnosis of Vascular Dementia of the Binswanger Type?

Whilst carrying out a pilot study with a structured questionnaire examining the difference in insight between a group of patients with Alzheimer's Disease and a second group with Vascular Dementia of the Binswanger Type, the incidental observation was made that the group of patients with Vascular Dementia of the Binswanger Type demonstrated more obsessional behaviour than the group of patients with Alzheimer's Disease. The obsessional behaviour differed from classical obsessive compulsive disorder insofar as the subjects were unaware of it whilst at the same time resisting change.