Fractal cycles of sleep, a new aperiodic activity-based definition of sleep cycles

• DOI: 10.7554/elife.96784
• Publication Date: 2024-05-21T13:26:03Z
• Authors: Yevgenia Rosenblum; Mahdad Jafarzadeh...; Nico Adelhöfer; Paul Zerr; Melanie Furrer; Reto Huber; Famke F Roest; Axel Steiger; Marcel Zeising; Csenge G Horváth; Bence Schneider; Róbert Bódizs; Martin Dresler
• Keywords: Aperiodic graph; Sleep

Sleep cycles are defined as episodes of non-rapid eye movement (non-REM) sleep followed by an episode REM sleep. Fractal or aperiodic neural activity is a well-established marker arousal and stages measured using electroencephalography. We introduce new concept ‘fractal cycles’ sleep, time interval during which series fractal descend to their local minimum ascend the next maximum. assess correlations between classical (i.e. non-REM – REM) cycle durations study with skipped The sample comprised 205 healthy adults, 21 children adolescents 111 patients depression. found that (89±34 vs 90±25 min) correlated positively ( r =0.5, p<0.001). Children had shorter than young adults (76±34 94±32 min). algorithm detected in 91–98% cases. Medicated depression showed longer compared unmedicated state (107±51 92±38 age-matched controls (104±49 88±31 In conclusion, objective, quantifiable, continuous biologically plausible way display its cycles.