Role of Slow Waves and Sleep Apnea in Memory and Risk for Alzheimer's Disease

Untreated sleep apnea (short episodes of stopping breathing) is thought to contribute to difficulty with memory. The purpose of this study is determining what effects sleep apnea has on the specific ability to remember locations and as well as on proteins in your body that contribute to risk for Alzheimer disease, a disorder in which memory loss is a main feature. Visit 1: About Thirty (30) Minutes. During this visit:  A review of CPAP adherence will be done in order to ensure minimum required adherence.  A review of current medications to determine if they may act as confounders.  You will be consented (only if you were not consented during your clinical visit).  Your height and weight will be measured.  You will be given an assessment that will measure cognitive function.  You will fill out a video game experience questionnaire.  You will receive an actigraphy to wear for two weeks and a sleep diary.  You will be scheduled for a brain MRI. Visit 2: About Forty-Five (45) Minutes. During this visit:  You will have a brain MRI.This scan will be obtained prior to the collection of spinal fluid to determine any reasons that would compromise the safety of collecting the spinal fluid. Additionally we will collect information about the sizes of different parts of the brain. Visits 3-5: During your overnight sleep studies, one of 3 conditions will occur: 1) You will sleep through the night with your known therapeutic CPAP pressure. 2) CPAP pressure will be reduced during sleep in a stage-specific manner and will be returned to the therapeutic level when you exit that stage. It is estimated that CPAP will be reduced for 5- 40% of sleep. 3) CPAP pressure will be reduced and supplemental oxygen will be given during sleep in a stage-specific manner. CPAP will be returned to the therapeutic level and supplemental oxygen will be discontinued when you exit that stage. It is estimated that CPAP will be reduced and supplemental oxygen supplied for 5-40% of sleep. Each successive night of study will occur roughly 1-2 weeks after the prior night of study. The order of conditions across the three nights will be random, and you will experience all 3 distinct conditions. Please make sure that someone (i.e. a family member, friend, or partner) can be available to accompany you home after the testing, if need be.