Home Sleep Therapy System for Mild Cognitive Impairment

Several findings suggest that a deficit in deep sleep (stage N3) with increased age impairs ongoing memory consolidation possibly contributing to the memory decline of mild cognitive impairment (MCI). Furthermore, impaired N3 sleep also causes inadequate excretion of beta amyloids and tau protein, which over many years of poor sleep may contribute to the long term neural degeneration leading to Alzheimer's Disease (AD). The evidence to date implies a vicious circle: the buildup of neurotoxins impairs the slow wave stage of deep sleep, and the degree of sleep deficit appears to predict the buildup of neurotoxins and thus progression to AD [1]. The present project will create the Neurosom® Electric Sleep Therapy (NEST) system to allow researchers to conduct TES studies to improve sleep in seniors with MCI in their home setting. The system includes a simple battery-operated bluetooth headband for electroencephalography (EEG) and transcranial electrical stimulation (TES), linked with a powerful bedside nanocomputer for sleep EEG analysis and machine learning classification of sleep stages. Communication with cloud services provides support for data analysis, memory assessment, and reporting to the patient and physician. By implementing and testing the NEST system in the home environment, this project will provide cost-effective tools for monitoring physiologic and behavioral measures sleep quality at home. In addition, it will allow researchers to develop TES protocols for manipulating sleep neurophysiology, such as synchronizing sleep spindles and the slow oscillations of N3 sleep in at-risk populations. Although our focus is on TES to extend N3 sleep, the EEG headband assessment will also provide definitive sleep quality outcome measures to evaluate various approaches to sleep therapy in seniors with MCI, including: sleep hygiene, improved exercise, Cognitive Behavior Therapy for Insomnia, and new pharmacologic agents. The realistic goal from this project is improve the quality of sleep and memory function in older persons with MCI. If it proves feasible to improve sleep over many years, the more ambitious goal could be to delay or even avoid the onset of dementia in millions of healthy seniors. To provide preliminary data on this long-range goal, the Phase II trial will include serial plasma measures of beta amyloid excretion (AB40, AB42) to test the hypothesis that improved deep sleep may improve glymphatic clearance of toxic metabolites.