In reply
We read with great interest the letter of Dr Rao reporting early findings of an association between carotid stenosis and development of depression. This observation suggests that ischemia of the carotid vascular territory confers vulnerability to depression, because depression occurred within 6 months following the first TIA. Dr Rao's findings add to the body of literature suggesting that cerebrovascular disease predisposes to depression.1 An important question arises from these observations. What brain circuits account for vulnerability to "vascular depression?" This question can be approached by focusing on cognitive functions that require integrity of specific brain systems.