During REM sleep the CNS is intensely active, but the skeletal motor system is paradoxically forced into a state of muscle paralysis. The mechanisms that trigger REM sleep paralysis are a matter of intense debate. Two competing theories argue that it is caused by either active inhibition or reduced excitation of somatic motoneuron activity. Here, we identify the transmitter and receptor mechani...

Changes in sleep structure, and especially REM sleep, and in EEG activation were studied in relation to the cholinergic deficit found in Alzheimer's Disease (AD). With respect to sleep architecture, only REM sleep percent was reduced in AD patients compared to controls as a result of a decrease in mean REM episode duration. Different results were obtained in patients with progressive supranucle...

The objective of this study was to assess whether treatment with sustained-release bupropion (Wellbutrin-SR) produces alterations in electroencephalographic (EEG) sleep that are associated with clinical response to the drug. EEG sleep was measured in 20 patients with unipolar major depressive disorder before and after treatment with sustained-release bupropion. Each EEG sleep session consisted ...

OBJECTIVE To investigate how differences in oxygen saturation between non-REM (NREM) and REM sleep in patients according to the severity of sleep apnea. METHODS We studied 396 male patients diagnosed with simple snoring or obstructive sleep apnea syndrome (OSAS) on nocturnal polysomnography. Patients were divided into groups by the OSAS severity. We compared the average oxygen saturation betw...

BACKGROUND Arousal in response to increased airflow resistance during sleep, especially rapid eye movement sleep (REM), could be an important protective mechanism against asphyxia. METHODS The arousal response to the application of an external inspiratory resistance of 25 cm H2O/l/s was determined during REM and non-REM sleep in ten healthy men. RESULTS The number of arousals occurring with...

Intracellular signaling mechanisms within the pedunculopontine tegmental (PPT) nucleus for the regulation of recovery rapid eye movement (REM) sleep following REM sleep deprivation remain unknown. This study was designed to determine the role of PPT intracellular cAMP-dependent protein kinase A (cAMP-PKA) in the regulation of recovery REM sleep in freely moving rats. The results show that a bri...

BACKGROUND AND OBJECTIVES There is a strong demand for fast and predictable anesthesia recovery with few side effects. Choice of the hypnotic agent could impact on that. This study investigated the differences between recoveries after remifentanil-propofol and remifentanil-desflurane anesthesias guided by bispectral index (BIS®). METHODS Forty patients were randomly assigned into 2 groups acc...

Many recent studies indicate that acetylcholine (ACh) in the brainstem is involved in REM sleep generation. Local ACh release in the brainstem regions, responsible for REM sleep during sleep and wakefulness, has not so far been reported because of technical difficulties. With in vivo microdialysis and electrochemical detection, we investigated the relationship between ACh release and sleep-wake...

Seventeen unmedicated patients with narcolepsy-cataplexy and 17 age- and sex-matched controls were recorded polygraphically for 3 consecutive nights. Rapid eye movements (REMs), m. mentalis twitches and sawtooth waves in the EEG were visually scored. REM and twitch densities during REM sleep were significantly higher in the patients than in the controls. The distribution pattern of REMs and twi...

Flexible or 'fluid' cognitive processes are regarded as fundamental to problem solving and creative ability, requiring a specific neurophysiological milieu. REM-sleep dreaming is associated with creative processes and abstract reasoning with increased strength of weak associations in cognitive networks. REM sleep is also mediated by a distinctive neurophysiological profile, different to that of...