This study presents a novel mathematical modeling framework that is uniquely suited to investigating the structure and dynamics of the sleep-wake regulatory network in the brain stem and hypothalamus. It is based on a population firing rate model formalism that is modified to explicitly include concentration levels of neurotransmitters released to postsynaptic populations. Using this framework,...

Dopamine depletion is involved in the pathophysiology of Parkinson's disease, whereas hyperdopaminergia may play a fundamental role in generating endophenotypes associated with schizophrenia. Sleep disturbances are known to occur in both schizophrenia and Parkinson's disease, suggesting that dopamine plays a role in regulating the sleep-wake cycle. Here, we show that novelty-exposed hyperdopami...

This study was aimed to explore the sleep/wake states related cortico-pontine theta carrier frequency phase shift following a systemically induced chemical axotomy of the monoaminergic afferents within a brain of the freely moving rats. Our experiments were performed in 14 adult, male Sprague Dawley rats, chronically implanted for sleep recording. We recorded sleep during baseline condition, fo...

Neuroimaging studies have produced seemingly contradictory findings in regards to the pathophysiology of insomnia. Although most study results are interpreted from the perspective of a "hyperarousal" model, the aggregate findings from neuroimaging studies suggest a more complex model is needed. We provide a review of the major findings from neuroimaging studies, then discuss them in relation to...

STUDY OBJECTIVE To assess the performance of automatic sleep scoring software (ASEEGA) based on a single EEG channel comparatively with manual scoring (2 experts) of conventional full polysomnograms. DESIGN Polysomnograms from 15 healthy individuals were scored by 2 independent experts using conventional R&K rules. The results were compared to those of ASEEGA scoring on an epoch-by-epoch basi...

Korobeinikov and Wake [9] introduced a family of Lyapunov functions for three-compartmental epidemiological models which appear to be useful for more sophisticated models. In this paper we have reinvestigated the models of Korobeinikov and Wake [9] with different incidences. The basic reproduction number 0 R is identified and local stability of the equilibrium states is discussed. The Global st...

a Department of Geography, University of Denver, 2050 East Iliff Ave., Denver, CO 80208, United States b Center for Energy Environment and Sustainability, Department of Biology, Wake Forest University, 1834 Wake Forest Rd., Winston-Salem, NC 27109, United States c School of Natural and Built Environments, University of South Australia, Mawson Lakes, Adelaide, SA, 5001, Australia d Barbara Hardy...

Sleep-wake states are impaired in various neurological disorders. Impairment of sleep-wake states can be an early condition that exacerbates these disorders. Therefore, treating sleep-wake dysfunction may prevent or slow the development of these diseases. Although many gene products are likely to be involved in the sleep-wake disturbance, hypnotics and psychostimulants clinically used are limit...

Understanding the inherent dynamics of the EEG associated to sleep-waking can provide insights into its basic neural regulation. By characterizing the local properties of the EEG using power spectrum, empirical mode decomposition (EMD) and Hilbert-spectral analysis, we can examine the dynamics over a range of time-scales. We analyzed rat EEG during wake, NREMS and REMS using these methods. The ...

Aim: The effect of orexin on wakefulness has been shown to be largely mediated by activation of histaminergic neurons via orexin receptor-2 (OX2R). Consistently, OX2R mRNA is abundantly expressed in histaminergic neurons in the tuberomammillary nucleus (TMN). However, orexin receptors in the other regions of the brain might also play important roles in maintenance of wakefulness. To dissect the...