Insomnia Characterization: From Hypnogram to Graph Spectral Theory

Ramiro Chaparro-Vargas, Beena Ahmed, Niels Wessel, Thomas Penzel, Dean Cvetkovic

Research output: Contribution to journalArticle

1 Citation (Scopus)


Objective: To quantify and differentiate control and insomnia sleep onset patterns through biomedical signal processing of overnight polysomnograms. Methods: The approach consisted of three tandem modules: 1) biosignal processing module, which used state-space time-varying autoregressive moving average (TVARMA) processes with recursive particle filter, 2) hypnogram generation module that implemented a fuzzy inference system (FIS), and 3) insomnia characterization module that discriminated between control and subjects with insomnia using a logistic regression model trained with a set of similarity measures (d1, d2, d3, d4). The study employed sleep onset periods from 16 control and 16 subjects with insomnia. Results: State-spaced TVARMA processes with recursive particle filtering provided resilience to nonlinear, nonstationary, and non-Gaussian conditions of biosignals. FIS managed automated sleep scoring robust to intersubjects' and interraters' variability. The similarity distances quantified in a scalar measure the transitions amongst sleep onset stages, computed from expert and automated hypnograms. A statistical set of unpaired two-tailed t-tests suggested that distances d1, d2, and d3 had larger statistical significance (pd1<6.5 × 10-5,pd2<2.1 × 10-4,pd3<4.5 × 10-7) to characterize sleeping patterns. The logistic regression model classified control and subjects with insomnia with sensitivity 87%, specificity 75%, and accuracy 81%. Conclusion: Our approach can perform a supportive role in either biosignal processing, sleep staging, insomnia characterization, or all the previous, coping with time-consuming procedures and massive data volumes of standard protocols. Significance: The introduction of graph spectral theory and logistic regression for the diagnosis of insomnia represents a novel concept, attempting to describe complex sleep dynamics throughout transitions networks and scalar measures.

Original languageEnglish
Article number7373576
Pages (from-to)2211-2219
Number of pages9
JournalIEEE Transactions on Biomedical Engineering
Issue number10
Publication statusPublished - 1 Oct 2016



  • Fuzzy logic
  • graph spectral theory
  • insomnia
  • polysomnogram (PSG)
  • sleep onset period

ASJC Scopus subject areas

  • Biomedical Engineering

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