Small blockages in arteries supplying blood to the brain occur quiet commonly in older adults without causing symptoms. Nonetheless, these "silent" strokes do damage and have a negative impact on mental function, according to German investigators. 

As described in the Journal of the American Geriatrics Society, Dr. Klaus Berger of the University of Munster and colleagues examined 267 community-dwelling subjects between the ages of 65 and 83 years. 

The researchers used MRI brain scans to detect the presence of silent strokes. Rating scales for self-perceived health status, activities of daily living, cognitive function, and depression were used to assess the effect of silent strokes on health. 

Silent stroke was identified in 34 patients (12.7 percent). An association was seen between silent stroke and a history of hypertension or heart surgery. 

Impairments on the Mini-Mental State Examination test were found in subjects with silent stroke. These patients also showed deficits in mental activities relating to procedural speed, memory, and motor performance compared to those without silent stroke. 

"Determining the presence of silent stroke using brain imaging may...contribute to identifying individuals at risk for developing gradual neurological deficits and cognitive decline," Berger and colleagues write.