Sleep

Sleep is an essential behavior, taking up about approximately one third of our lives. Therefore, it is not surprising that sleep disorders have a profound impact on quality of life.

Sleep disorders are typically characterized by subjective symptoms that change over time and under the influence of external factors. Likewise, objective parameters fluctuate as well. In the current clinical practice, these temporal aspects are almost completely ignored. Moreover, the current diagnostic techniques capture only a very limited part of the underlying pathophysiology, still using EEG-based polysomnographic measurements developed in the '60s. Therefore, there is a strong need for advanced sleep monitoring techniques that can obtain both subjective and objective data over the long term in natural settings, and that assess the various disorders on a deeper pathophysiological level.

Within the BM/d Research Lab, we are working together with the Center for Sleep Medicine Kempenhaeghe and the TU/e department of  Industrial Design on alternative technologies to measure (a derivative of) sleep and on innovative solutions that can help with diagnosis and monitoring of sleep disorders. The research is mainly done on two of the most prevalent sleep disorders: obstructive sleep apnea (OSA) and insomnia.

OSA is caused by recurring obstruction of the upper airway during sleep, either partial or complete. Breathing cessation often leads to repetitive drops in blood oxygen saturation. Furthermore, these episodes are almost always accompanied by snoring sounds. Our goal is to enable reliable OSA screening with unobtrusive systems that can detect drops in blood oxygen saturation as well as snoring sounds.

The routine diagnosis of insomnia is mostly based not on PSG but on subjective symptoms, sleep diaries, and questionnaires. However, objective measures of relevant physiological parameters, obtained from e.g. polysomnography (PSG) and photoplethysmography (PPG), may provide new insights for the pathophysiology of insomnia, which is currently not completely elucidated. Insomnia patients form a large and diverse group, presumably reacting differently to generic insomnia treatment. Therefore, we aim at studying the mechanisms underlying the heterogeneity in the insomnia population and the response to treatment, using home-based PSG assessment of sleep structure, long-term continuous PPG parameters, and neuropsychological testing.