Two Sides of the Same Pillow: Unfolding the Relationship between Objective and Subjective Sleep Quality with Unsupervised Learning

Advances in digital health allow us to take an active part in monitoring and improving our sleep quality. Both, objectively recorded and subjectively perceived sleep quality impacts our general health and well-being. This research shows how these two dimensions of sleep quality can be captured with smartwatches and digital symptom trackers. We contribute to the gap in the literature on how recorded values from wearables and user-generated content from mobile applications can elevate each other. Analysing the recorded and re- ported sleep quality in a longitudinal sleep study (n=45) shows differences in how partic- ipants perceive their sleep. We address this need for personalization, by creating clusters of participants with a similar perception of sleep using unsupervised machine learning. Analysing these clusters provides us with a more wholesome understanding of their sleep quality and raises awareness for the uniqueness of individuals in digital health

Towards a Deeper Understanding of Sleep Stages through their Representation in the Latent Space of Variational Autoencoders

Artificial neural networks show great success in sleep stage classification, with an accuracy comparable to human scoring. While their ability to learn from labelled electroencephalography (EEG) signals is widely researched, the underlying learning processes remain unexplored. Variational autoencoders can capture the underlying meaning of data by encoding it into a low-dimensional space. Regularizing this space furthermore enables the generation of realistic representations of data from latent space samples. We aimed to show that this model is able to generate realistic sleep EEG. In addition, the generated sequences from different areas of the latent space are shown to have inherent meaning. The current results show the potential of variational autoencoders in understanding sleep EEG data from the perspective of unsupervised machine learning

Anomaly detection in sleep : detecting mouth breathing in children

Publisher Copyright: © 2023, The Author(s).Identifying mouth breathing during sleep in a reliable, non-invasive way is challenging and currently not included in sleep studies. However, it has a high clinical relevance in pediatrics, as it can negatively impact the physical and mental health of children. Since mouth breathing is an anomalous condition in the general population with only 2% prevalence in our data set, we are facing an anomaly detection problem. This type of human medical data is commonly approached with deep learning methods. However, applying multiple supervised and unsupervised machine learning methods to this anomaly detection problem showed that classic machine learning methods should also be taken into account. This paper compared deep learning and classic machine learning methods on respiratory data during sleep using a leave-one-out cross validation. This way we observed the uncertainty of the models and their performance across participants with varying signal quality and prevalence of mouth breathing. The main contribution is identifying the model with the highest clinical relevance to facilitate the diagnosis of chronic mouth breathing, which may allow more affected children to receive appropriate treatment.Peer reviewe