STUDY OBJECTIVES One of the most important caveats of ambulatory devices is the inability to record and stage sleep. We assessed an algorithm determining 4 different stages: wake, light sleep, deep sleep, and REM sleep using signals derived from the portable monitor Watch-PAT100 (PAT recorder). METHODS Participants (38 normal subjects and 189 patients with obstructive sleep apnea [OSA]) under...

Controversy continues to surround the monosynaptic and polysynaptic spinal reflexes during the different stages of sleep. In animal studies both of these reflexes were found to be depressed during desynchronized sleep. In humans, the H reflex was unchanged whereas the second component of the nociceptive flexion reflex was increased. However, abolition of the H reflex and F waves during REM slee...

All sleep stages contain epochs with high-amplitude electrophysiological phasic events, alternating with quieter "core periods." High-amplitude and core state properties cannot be disentangled with PET and fMRI. Here from high temporal resolution magnetoencephalography data, regional changes in neuronal activity were extracted during core periods in different frequency bands for each sleep stag...

This paper investigates the automated detection of a patient’s breathing rate and heart rate from their skin conductivity as well as sleep stage scoring and breathing event detection from their EEG. The software developed for these tasks is tested on data sets obtained from the sleep disorders unit at the Adelaide Women’s and Children’s Hospital. The sleep scoring and breathing event detection ...

An actigraph extended with electroencephalography (EEG), electroocculography (EOG) and electromyography (EMG) was compared to polysomnography in two studies on patients suffering from sleep disordered breathing. Study A with 30 subjects used a single lead EEG, and study B with 20 subjects used EOG and EMG in addition. Sleep was scored according to Rechtschaffen and Kales rules. Total sleep time...

Throughout the ages, sleep has been considered akin to death; indeed, Homer referred to sleep as the ‘brother of death’. However, the advent of electroecephalography (EEG) has expelled this misconception and sleep is now recognised as consisting of active brain states during which many biological processes occur, such as synaptic plasticity and memory consolidation. Sleep can be broadly divided...

Background: Sleep has been associated with the regulation of energy balance, yet the relation between sleep stages and energy expenditure remains unclear. Objective: The objective was to investigate the relation between sleep stages and energy expenditure, with sleep stage and overnight energy expenditure patterns taken into account. Design: Thirteen subjects aged (mean 6 SD) 24.3 6 2.5 y with ...

VISUAL SLEEP STAGING IS STILL THE MOST WIDELY USED PROCEDURE TO ANALYZE SLEEP. IT ALLOWS ONE TO SUBDIVIDE SLEEP RECORDINGS INTO discrete states or stages, defined by coherent and recurrent patterns of one1 or more2 electrophysiologic signals. Based on this method, human sleep has been defined as an alternating sequence of 4 stages of non-rapid eye movement sleep (NREM stages 1 to 4), and rapid ...

BACKGROUND Sleep has been associated with the regulation of energy balance, yet the relation between sleep stages and energy expenditure remains unclear. OBJECTIVE The objective was to investigate the relation between sleep stages and energy expenditure, with sleep stage and overnight energy expenditure patterns taken into account. DESIGN Thirteen subjects aged (mean ± SD) 24.3 ± 2.5 y with...

Polysomnography (PSG) has been extensively studied for sleep staging, where sleep stages are usually classified as wake, rapid-eye-movement (REM) sleep, or non-REM (NREM) sleep (including light and deep sleep). Respiratory information has been proven to correlate with autonomic nervous activity that is related to sleep stages. For example, it is known that the breathing rate and amplitude durin...