From the article:
The study looked at results from 54 adults (between the ages of 55 to 80), who also possessed at least one risk factor for a stroke, such as high blood pressure, high cholesterol, diabetes, sleep apnea, a history of smoking, past mini strokes and advanced age above 75.
Research participants had their brains scanned by MRI and scientists analyzed brain tissue damage, specifically in relation to white matter, to determine injuries caused by cerebral small vessel disease. They also took part in a number of neurocognitive tests and questionnaires that assessed their attention and executive function.