Liguori C, et al. - Via involving drug-naïve individuals who were consecutively referred to the Neurological Clinic of the University Hospital of Rome “Tor Vergata” between January 2012 and July 2016, researchers studied nocturnal sleep architecture changes, Alzheimer disease (AD) biomarkers in the CSF, and memory impairment across various levels of neurocognitive functioning and impairment ranging from the cognitively normal (CN) condition to subjective cognitive impairment (SCI), mild cognitive impairment (MCI), and AD dementia. The sample consisted of patients affected by SCI, MCI, mild AD, and moderate-to-severe AD along with CN individuals as controls. According to results, biomarkers of sleep (both rapid eye movement (REM) and non-REM sleep), memory and CSF AD are strongly interrelated in AD development from the earliest asymptomatic and preclinical stages of AD-related disease since the earliest and preclinical stages of the disease.