Sleepy during the day? It could be an early warning sign of dementia, study suggests Fox NewsStudy expands the science on the link between sleep and dementia CNNPoor sleep quality linked to incident motoric cognitive risk syndrome Medical XpressVitamin D deficiency to cognitive decline: Surprising reasons why you are feeling sleepy during the day The Times of IndiaOne Stage of Sleep Seems to Be Critical in Reducing Dementia Risk ScienceAlert