Increased attention to the prevalence of excessive sleepiness has led to a clear need to treat this symptom, thus reinforcing the need for a greater understanding of the neurobiology of sleep and wakefulness. Although the physiological mechanisms of sleep and wakefulness are highly interrelated, recent research reveals that there are distinct differences in the active brain processing and the s...

BACKGROUND Irregular sleep-wake cycles and cognitive impairment are frequently observed in schizophrenia, however, how they interact remains unclear. AIMS To investigate the repercussions of circadian rhythm characteristics on cognitive performance and psychopathology in individuals with schizophrenia. METHOD Fourteen middle-aged individuals diagnosed with schizophrenia underwent contin...

In this study we have constructed a mathematical model of a recently proposed functional model known to be responsible for inducing waking, NREMS and REMS. Simulation studies using this model reproduced sleep-wake patterns as reported in normal animals. The model helps to explain neural mechanism(s) that underlie the transitions between wake, NREMS and REMS as well as how both the homeostatic s...

Disturbed sleep is a major clinical problem in Alzheimer's disease (AD). Apolipoprotein epsilon4 (APOE epsilon4) carrier status may increase risk of AD, yet there are no data on relations between APOE status and progression of sleep disturbance in AD. The objective of this study was to determine if sleep parameters in AD patients change over time as a function of APOE carrier status. Forty-four...

In this paper we investigate the optimal control approach for the active control of the circular cylinder wake flow considered in the laminar regime (Re = 200). The objective is the minimization of the mean total drag where the control function is the time harmonic angular velocity of the rotating cylinder. When the Navier-Stokes equations are used as state equations, the discretization of the ...

The importance of sleep in providing psychophysiological recovery in elite athletes is often overlooked. In other populations (eg shift workers and adolescent students), sleep hygiene education may serve to acutely improve sleep indices. However, this is yet to be examined in an elite athlete setting. Therefore, the aim of the current study was to evaluate the effect of a sleep hygiene educatio...

In this study, call detail records (CDR), covering Budapest, Hungary, are processed to analyze the circadian rhythm of subscribers. An indicator, called wake-up time, is introduced describe behavior a group It defined as time when mobile phone activity rises in morning. Its counterpart falls evening. Inhabitant and area-based aggregation also presented. The former consider people who live an ar...

BACKGROUND A disturbed circadian rhythm seems to be a causal factor in the occurrence of depressive disorders in patients with Parkinson's disease (PD). The circadian rhythm can be restored with light. Therefore, Bright Light Therapy (BLT) might be a new treatment option for depression in PD patients. METHODS/DESIGN In this double-blind controlled trial, 84 subjects with idiopathic PD are ran...

The pineal hormone melatonin is involved in the circadian regulation and facilitation of sleep, the inhibition of cancer development and growth, and the enhancement of immune function. Individuals, such as night shift workers, who are exposed to light at night on a regular basis experience biological rhythm (i.e., circadian) disruption including circadian phase shifts, nocturnal melatonin suppr...