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Mathematical models of sleep regulation

Peter Achermann
2003 Frontiers in Bioscience  
(45) and formalized by Achermann and Borbély (46) the model was adapted so that it is the change of S, rather than its level, which is proportional to the momentary value of SWA.  ... 
doi:10.2741/1064 pmid:12700054 fatcat:veh5kubk6zhd3cf4uo6lrjl5mm

Insufficient Non-REM Sleep Intensity in Narcolepsy-Cataplexy

Ramin Khatami, Hans-Peter Landolt, Peter Achermann, Julia V. Rétey, Esther Werth, Johannes Mathis, Claudio L. Bassetti
2007 Sleep  
by emotions) and, facultatively, by other rapid eye movement (REM) sleep phenomena such as sleep paralysis and hallucinations (narcoleptic tetrad). Patients with narcolepsy with cataplexy have normal amounts of sleep over 24 hours, 1-3 but their day-night sleep distribution shows greater amounts of daytime sleep and fragmented nocturnal sleep. 1,2,4 Disturbed nocturnal sleep is often referred to as the fifth symptom of the narcoleptic tetrad and becomes particularly disabling with disease
more » ... ssion and may contribute to excessive daytime sleepiness in this disorder. 1 Patients with narcolepsy-cataplexy may start nocturnal sleep with REM sleep (sleep onset REM period [SOREMP]). Once sleep is initiated, a high number of sleep-stage transitions, short bouts of wakefulness and/or sustained wake periods occur within the sleep period. 2 It has been hypothesized that a dysfunctional homeostatic NREM sleep-regulatory process contributes to sleep fragmentation in patients with narcolepsy-cataplexy. 3, 5, 6 The process, referred to as sleep homeostasis, enables organisms to compensate for transient sleep loss from an average "reference level" by changes of sleep duration and sleep intensity. The 2-process model of sleep regulation 7 assumes that the interaction of the sleep-wake dependent homeostatic process S and the circadian process C (which is independent of sleep and wakefulness) determines the timing, duration, and stability of sleep and wakefulness. Process S can be derived from the time course of electroencephalogram (EEG) slow wave activity (SWA; power within 0.75-4.5 Hz range) in NREM sleep. SWA dissipates roughly exponentially across successive NREM sleep episodes. 8 The level of SWA at sleep onset is a function of the duration of prior wakefulness. SWA at sleep onset rises after prolonged wakefulness and declines after extended sleep. The temporal dynamics of SWA are characterized also by an opposite relationship to spindle-frequency activity (SFA; power within 12-14 Hz range). 9-11 SFA exhibits an increasing trend over successive NREM sleep episodes. The intra-episodic time course of SFA resembles a U-shaped pattern that opposes the time course of SWA within a NREM sleep episode. Specifically, both activities, SWA and SFA, rise at the beginning and decline at the end of a NREM sleep episode. This positive correlation reverses in the middle of a NREM sleep episode, in which SWA peaks while SFA exhibits a trough. 9 Based on the dynamics of EEG SWA in 3 published studies, 3 hypotheses about abnormal sleep homeostasis in narcolepsycataplexy have been developed. (1) NREM sleep homeostasis is essentially intact in patients with narcolepsy-cataplexy, as shown by an exponential decline of SWA across the sleep period 5,12 and enhanced SWA in patients with narcolepsy-cataplexy and in controls after sleep deprivation. 5 Following 24 hours of
doi:10.1093/sleep/30.8.980 pmid:17702267 pmcid:PMC1978383 fatcat:grgq4amnwra4rmlbbcxelgsyru

Inter-individual Differences in the Dynamics of Sleep Homeostasis

Thomas Rusterholz, Roland Dürr, Peter Achermann
2010 Sleep  
INDIVIDUAL DIFFERENCES IN SLEEP HOMEOSTASIS Inter-individual Differences in the Dynamics of Sleep Homeostasis Thomas Rusterholz, MSc 1,3 ; Roland Dürr, PhD 1 ; Peter Achermann, PhD 1,2,3 1 Study Design  ... 
doi:10.1093/sleep/33.4.491 pmid:20394318 pmcid:PMC2849788 fatcat:zyuqfaw44fcljbk4gcrtsks73q

Linear causal filtering: definition and theory [article]

Roberto Pascual-Marqui, Rolando J Biscay, Jorge Francisco Bosch-Bayard, Pascal Luc Faber, Peter Achermann, Toshihiko Kinoshita, Kieko Kochi
2021 bioRxiv   pre-print
ij Tj = = t Nt →    X ) 2 2 Eq. 55 Amp ( ) 21 ji Phase ( ) 11 t ET NN ( ,2 Tj ji Nt ; ET NN ( ) ( ( ,1 ) 2 ,2 i ,1 j ji t ; i ji t ; t ; ji → ) ) 11 t Pascual-Marqui, Biscay, Bosch-Bayard, Achermann  ... 
doi:10.1101/2021.05.01.442232 fatcat:b5x5zndy35adljtkbtjpvbxwia

Cognitive Performance Measures in Bioelectromagnetic Research - Critical Evaluation and Recommendations

Sabine J Regel, Peter Achermann
2011 Environmental Health  
Peter Achermann received previously support from the Swiss Research Foundation on Mobile Communication (FSM), a non-profit foundation sponsored by ETH Zurich, Nokia Siemens Networks, Mobilezone, Orange  ...  Table 1 1 RF EMF effects on cognitive performance in studies with a within-subject design (Continued)Regel and Achermann Environmental Health 2011, 10:10 http://www.ehjournal.net/content/10/1/10 Haarala  ...  High Allow for sufficient exposure duration; consider potential carryover effects in a crossover design; allow for sufficient time interval ('washout period') between conditions Regel and Achermann  ... 
doi:10.1186/1476-069x-10-10 pmid:21266038 pmcid:PMC3041732 fatcat:5upduroyr5ez7glgqtlwvxriyu

Sleep Homeostasis and Models of Sleep Regulation

Alexander A. Borb, Peter Achermann
1999 Journal of Biological Rhythms  
Ultradian dynamics of SWA (Achermann et al., 1993; Achermann and Borbély, 1992 REMT(t): REMS trigger signal (1 if activated, otherwise 0) derived from empirical data (Achermann et al., 1993) or  ...  Depending on the type of simulation, some of the parameters or initial conditions need to be changed (Achermann et al., 1993; Achermann and Borbély, 1992) .  ... 
doi:10.1177/074873099129000894 pmid:10643753 fatcat:5sutzni5bvgyrlmxqoovcfijs4

Sleep Homeostasis and Models of Sleep Regulation [chapter]

Peter Achermann, Alexander A. Borbély
2011 Principles and Practice of Sleep Medicine  
Ultradian dynamics of SWA (Achermann et al., 1993; Achermann and Borbély, 1992 REMT(t): REMS trigger signal (1 if activated, otherwise 0) derived from empirical data (Achermann et al., 1993) or  ...  Depending on the type of simulation, some of the parameters or initial conditions need to be changed (Achermann et al., 1993; Achermann and Borbély, 1992) .  ... 
doi:10.1016/b978-1-4160-6645-3.00037-2 fatcat:desadrfbunadxnttls4apvzsta

Sleep Homeostasis and Models of Sleep Regulation [chapter]

Peter Achermann, Alexander A. Borbély
2017 Principles and Practice of Sleep Medicine  
Ultradian dynamics of SWA (Achermann et al., 1993; Achermann and Borbély, 1992 REMT(t): REMS trigger signal (1 if activated, otherwise 0) derived from empirical data (Achermann et al., 1993) or  ...  Depending on the type of simulation, some of the parameters or initial conditions need to be changed (Achermann et al., 1993; Achermann and Borbély, 1992) .  ... 
doi:10.1016/b978-0-323-24288-2.00036-2 fatcat:l3jolkv7hjgodbq73jthalyq4y

Sleep Homeostasis and Models of Sleep Regulation [chapter]

Alexander A. Borbély, Peter Achermann
2005 Principles and Practice of Sleep Medicine  
Ultradian dynamics of SWA (Achermann et al., 1993; Achermann and Borbély, 1992 REMT(t): REMS trigger signal (1 if activated, otherwise 0) derived from empirical data (Achermann et al., 1993) or  ...  Depending on the type of simulation, some of the parameters or initial conditions need to be changed (Achermann et al., 1993; Achermann and Borbély, 1992) .  ... 
doi:10.1016/b0-72-160797-7/50040-9 fatcat:rj6ovcdwdnek3mwsini6kajp3u

Developmental Changes in Sleep Oscillations during Early Childhood

Eckehard Olbrich, Thomas Rusterholz, Monique K. LeBourgeois, Peter Achermann
2017 Neural Plasticity  
LeBourgeois and the Swiss National Science Foundation (32003B_146643) to Peter Achermann.  ...  For a detailed description of the original algorithm and its application to adult human sleep EEG data, see Olbrich and Achermann [13] and Olbrich et al. [14, 17] .  ...  LeBourgeois and Peter Achermann shared the last authorship.  ... 
doi:10.1155/2017/6160959 pmid:28845310 pmcid:PMC5563422 fatcat:dnd766pohjfajcs4vy7lne2skm

Cortical neuronal activity determines the dynamics of local sleep homeostasis [article]

Christopher William Thomas, Mathilde C. C. Guillaumin, Laura E. McKillop, Peter Achermann, Vladyslav V. Vyazovskiy
2019 bioRxiv   pre-print
., 1991a; Achermann et al., 254 1993; Huber et al., 2000a; Vyazovskiy et al., 2007; Guillaumin et al., 2018).  ...  Neuron 75, 1001-1007. 583 Guillaumin, M.C.C., McKillop, L.E., Cui, N., Fisher, S.P., Foster, R.G., de Vos, M., Peirson, S.N., Achermann, 584 P., and Vyazovskiy, V.V. (2018).  ... 
doi:10.1101/756270 fatcat:izzam6g6vrbghaizazggub7xdy

Decline of long-range temporal correlations in the human brain during sustained wakefulness [article]

Christian Meisel, Kimberlyn Bailey, Peter Achermann, Dietmar Plenz
2017 arXiv   pre-print
Sleep is crucial for daytime functioning, cognitive performance and general well-being. These aspects of daily life are known to be impaired after extended wake, yet, the underlying neuronal correlates have been difficult to identify. Accumulating evidence suggests that normal functioning of the brain is characterized by long-range temporal correlations (LRTCs) in cortex, which are supportive for decision-making and working memory tasks. Here we assess LRTCs in resting state human EEG data
more » ... g a 40-hour sleep deprivation experiment by evaluating the decay in autocorrelation and the scaling exponent of the detrended fluctuation analysis from EEG amplitude fluctuations. We find with both measures that LRTCs decline as sleep deprivation progresses. This decline becomes evident when taking changes in signal power into appropriate consideration. Our results demonstrate the importance of sleep to maintain LRTCs in the human brain. In complex networks, LRTCs naturally emerge in the vicinity of a critical state. The observation of declining LRTCs during wake thus provides additional support for our hypothesis that sleep reorganizes cortical networks towards critical dynamics for optimal functioning.
arXiv:1706.03835v1 fatcat:eoe5olad5jdzle7nwi4r6unila

Effect of Rocking Movements on Respiration

Ximena Omlin, Francesco Crivelli, Lorenz Heinicke, Sebastian Zaunseder, Peter Achermann, Robert Riener, Thomas Penzel
2016 PLoS ONE  
Peter Wolf, Dr.  ... 
doi:10.1371/journal.pone.0150581 pmid:26954500 pmcid:PMC4783003 fatcat:y6yjjdbuzzhrjjjaqtzrv2zp7i

Francisella tularensis periprosthetic joint infections diagnosed with growth in cultures

Aleš Chrdle, Tomáš Trnka, David Musil, Sandro F. Fucentese, Peter Bode, Peter M Keller, Yvonne Achermann
2019 Journal of Clinical Microbiology  
Tularemia caused by Francisella tularensis is a zoonotic infection of the Northern Hemisphere that mainly affects skin, lymph nodes, bloodstream and lungs. Other manifestations of tularemia are very rare, especially with musculoskeletal involvement. Presenting in 2016, we diagnosed two cases of periprosthetic knee joint infections (PJI) caused by Francisella tularensis in Europe (one in Switzerland, one in Czech Republic). We only found two other PJI cases in literature, another knee PJI
more » ... ed 1999 in Ontario, Canada, and one hip PJI in Illinois, USA 2017. Diagnosis was made in all cases by positive microbiological cultures after 3, 4, 7, and 12 days. All were successfully treated, two cases with exchange of the prosthesis, one with debridement and retention, and one with repeated aspiration of the synovial fluid only. Antibiotic treatment was given between 3 weeks and 12 months wither either ciprofloxacin/rifampin or with doxycycline alone or doxycycline in combination with gentamicin. Zoonotic infections should be considered in periprosthetic infections in particular in culture negative PJIs with a positive histology or highly elevated leucocytes in synovial aspiration. Here we recommend to prolong cultivation time up to 14 days, perform specific PCR tests, and/or do epidemiologically appropriate serological tests for zoonotic infections including that for F. tularensis.
doi:10.1128/jcm.00339-19 pmid:31189580 pmcid:PMC6663894 fatcat:2eramtoaknhuncpw3nsnn27fna

Association between sleep duration and intelligence scores in healthy children

Anja Geiger, Peter Achermann, Oskar G. Jenni
2010 Developmental Psychology  
Reference: Geiger, A., Achermann, P., & Jenni, O. G. (2010). Association between sleep duration and intelligence scores in healthy children.  ...  In regards to different aspects of sleep, "the highest correlation coefficients were observed between sleep period on weekends and full-scale IQ, fluid IQ, and working memory" (Geiger, Achermann, & Jenni  ... 
doi:10.1037/a0019679 pmid:20604614 fatcat:5e54duivsvayxesmkze6ts7tm4
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