Brain Sleep Deprivation MRI Effects (BEDTIME)

Open Masking, Micro Motionlogger Actigraph, 3T Siemens MRI, Sleep Deprivation, Nocturnal PSG

The primary purpose of this study is to explore the underlying mechanisms that link sleep to Alzheimer's disease (AD), with special focus on the clearance of metabolites in the extracellular space of the brain during sleep. Subjects will wear an actigraph for 1 week to determine regular daytime activity and sleep patterns. Subjects will then undergo partial sleep deprivation followed by 4 hours of in-lab nocturnal polysomnography (NPSG). Participants will be be asked to stay awake and active all day after the partial sleep deprivation with a new actigraphy secured by a hospital band to assure participants remain awake. They will seep inside an MRI machine for 90 minutes on the following night during their usual bedtime (established by 1 week actigraphy study.) Morphologic imaging, flow imaging and diffusion kurtosis imaging (DKI) will be performed on a 3T Siemens scanner.

Inclusion Criteria:

• Age range 21-30
• Capable of giving informed consent

Exclusion Criteria:

• Diagnosis of any brain disease or brain damage including significant trauma, hydrocephalus, seizures, mental retardation or other serious neurological disorders (e.g. Parkinson's disease or other movement disorders). Persons with silent cortical infarcts will be excluded. White matter lesions will not be exclusions.
• History of major psychiatric illness (e.g., schizophrenia, bipolar or life long history of major depression)
• Conditions that alter normal sleep patterns: irregular sleep-wake rhythms (based on one week at home monitoring with actigraphy), moderate to severe periodic limb movement while you sleep (PLMS) or Obstructive Sleep Apnea (OSA).
• History of claustrophobia.
• BMI≥30
• Significant history of alcoholism or drug abuse.
• Inability to avoid the use of alcohol or caffeine during the 48h before the MRI.
• Current pregnancy or intent to become pregnant during the period of study.
• Any electronic or ferromagnetic devices (e.g., pacemaker or surgical clips) that constitutes a hazard for MRI imaging.
• Any medications adversely affecting cognition, blood pressure, glucose metabolism, or sleep will result in exclusion.