Alzheimer’s disease and dementia are often considered to be the end result of an episode of hypoxia (lack of oxygen), which can occur through a stroke or concussion earlier in life. This hypoxia is considered to result in an increase of A-beta proteins, the accumulation of which is considered as the significant marker of Alzheimer’s disease. This study looks at the possibility that episodes of hypoxia can occur when individuals sleep in any microenvironment that becomes increasingly short of oxygen due to rebreathing. Rebreathing can occur when any individual inhales air that they have just exhaled. If this occurs in a restricted space, the result would be the depletion of oxygen over time accompanied by an increase in carbon dioxide. These microenvironments can occur when any individual sleeps with their head partially or completely covered by bedding, such as blankets, sheets, or pillows.