TY - JOUR
T1 - Automatic sleep classification using a data-driven topic model reveals latent sleep states
AU - Koch, Henriette
AU - Christensen, Julie A E
AU - Frandsen, Rune
AU - Zoetmulder, Marielle
AU - Arvastson, Lars
AU - Christensen, Soren R
AU - Jennum, Poul
AU - Sorensen, Helge B D
N1 - Copyright © 2014 Elsevier B.V. All rights reserved.
PY - 2014/9/30
Y1 - 2014/9/30
N2 - BACKGROUND: The golden standard for sleep classification uses manual scoring of polysomnography despite points of criticism such as oversimplification, low inter-rater reliability and the standard being designed on young and healthy subjects.NEW METHOD: To meet the criticism and reveal the latent sleep states, this study developed a general and automatic sleep classifier using a data-driven approach. Spectral EEG and EOG measures and eye correlation in 1s windows were calculated and each sleep epoch was expressed as a mixture of probabilities of latent sleep states by using the topic model Latent Dirichlet Allocation. Model application was tested on control subjects and patients with periodic leg movements (PLM) representing a non-neurodegenerative group, and patients with idiopathic REM sleep behavior disorder (iRBD) and Parkinson's Disease (PD) representing a neurodegenerative group. The model was optimized using 50 subjects and validated on 76 subjects.RESULTS: The optimized sleep model used six topics, and the topic probabilities changed smoothly during transitions. According to the manual scorings, the model scored an overall subject-specific accuracy of 68.3 ± 7.44 (% μ ± σ) and group specific accuracies of 69.0 ± 4.62 (control), 70.1 ± 5.10 (PLM), 67.2 ± 8.30 (iRBD) and 67.7 ± 9.07 (PD).COMPARISON WITH EXISTING METHOD: Statistics of the latent sleep state content showed accordances to the sleep stages defined in the golden standard. However, this study indicates that sleep contains six diverse latent sleep states and that state transitions are continuous processes.CONCLUSIONS: The model is generally applicable and may contribute to the research in neurodegenerative diseases and sleep disorders.
AB - BACKGROUND: The golden standard for sleep classification uses manual scoring of polysomnography despite points of criticism such as oversimplification, low inter-rater reliability and the standard being designed on young and healthy subjects.NEW METHOD: To meet the criticism and reveal the latent sleep states, this study developed a general and automatic sleep classifier using a data-driven approach. Spectral EEG and EOG measures and eye correlation in 1s windows were calculated and each sleep epoch was expressed as a mixture of probabilities of latent sleep states by using the topic model Latent Dirichlet Allocation. Model application was tested on control subjects and patients with periodic leg movements (PLM) representing a non-neurodegenerative group, and patients with idiopathic REM sleep behavior disorder (iRBD) and Parkinson's Disease (PD) representing a neurodegenerative group. The model was optimized using 50 subjects and validated on 76 subjects.RESULTS: The optimized sleep model used six topics, and the topic probabilities changed smoothly during transitions. According to the manual scorings, the model scored an overall subject-specific accuracy of 68.3 ± 7.44 (% μ ± σ) and group specific accuracies of 69.0 ± 4.62 (control), 70.1 ± 5.10 (PLM), 67.2 ± 8.30 (iRBD) and 67.7 ± 9.07 (PD).COMPARISON WITH EXISTING METHOD: Statistics of the latent sleep state content showed accordances to the sleep stages defined in the golden standard. However, this study indicates that sleep contains six diverse latent sleep states and that state transitions are continuous processes.CONCLUSIONS: The model is generally applicable and may contribute to the research in neurodegenerative diseases and sleep disorders.
KW - Aged
KW - Brain
KW - Electroencephalography
KW - Electrooculography
KW - Eye
KW - Female
KW - Humans
KW - Male
KW - Middle Aged
KW - Nocturnal Myoclonus Syndrome
KW - Ocular Physiological Phenomena
KW - Parkinson Disease
KW - Pattern Recognition, Automated
KW - Polysomnography
KW - Probability
KW - REM Sleep Behavior Disorder
KW - Sensitivity and Specificity
KW - Signal Processing, Computer-Assisted
KW - Sleep
U2 - 10.1016/j.jneumeth.2014.07.002
DO - 10.1016/j.jneumeth.2014.07.002
M3 - Journal article
C2 - 25016288
SN - 0165-0270
VL - 235
SP - 130
EP - 137
JO - Journal of Neuroscience Methods
JF - Journal of Neuroscience Methods
ER -