This article discusses the definition, classification and pathogenetic mechanisms of cognitive functions in arterial hypertension. The authors discuss the capabilities of the different classes of antihypertensive drugs in correction of cognitive impairments and prevention of dementia. The authors also discuss the advantages of the angiotensin II receptor blockers in prevention of dementia and in their potential mechanisms of cerebral protection. The article describes in detail the possibilities of valsartan in correction of cognitive impairments associated with arterial hypertension, the advantages of valsartan in comparison with calcium antagonists and its unique neuroprotective mechanisms. We show our own results of the study concerning fixed-dose combination of valsartan and hydrochlorothiazide, and find out that this combination has high antihypertensive and cerebral protection (capacity to improve cognitive function) and effectiveness.