Sleep, pericyte subtypes and cognitive decline in adults https://academic.oup.com/brain/advance-article/doi/10.1093/brain/awaf161/8189044 Disrupted sleep damages blood vessels in brain and may increase dementia risk https://medicalxpress.com/news/2025-07-disrupted-blood-vessels-brain-dementia.html Sleep disruption directly causes damage to brain blood vessels and blood flow