, sleep architecture and sleep duration were similar for all three ventilator modes as the difference between the modes for the 15 subjects were not statistically different.
Negative esophageal pressure ([less than]-10 cm [H.sub.2]O) with sleep fragmentation
The effect of sleep fragmentation
on cognitive processing using computerized topographic brain mapping.
In the individual who suffers from untreated sleep apnoea, deficits may occur in a variety of brain functions, due both to sleep loss (in the form of sleep fragmentation
or lack of slow wave sleep) (7,8) or recurrent hypoxaemia (7,9,10).
Often, this results in frequent awakenings that result in sleep fragmentation
and discontinued use.
Particularly in these vulnerable children, avoid sleep deprivation and conditions that may foster sleep fragmentation
, such as untreated obstructive sleep apnea or alcohol use.
The resulting reduction (hypopnea) or cessation (apnea) of airflow (inspiratory flow limitation) produces dips in oxygen saturation, increases in inspiratory efforts against the obstructed airway, and sleep fragmentation
.  These nocturnal physiologic events lead to a variety of neurophysiologic and cardiovascular complications, including daytime hypersomnolence, cognitive impairments, systemic and pulmonary hypertension, and cardiac arrhythmias (figure 1).
The symptoms of various sleep disorders in PD patients include night insomnia, increased sleepiness, sleep fragmentation
, reduced sleep efficiency, and rapid eye movement (REM) sleep behavior disorder, thus having a serious impact on the patient's sleep quality and increasing the risk of dementia. Therefore, cognitive dysfunction and sleep disorders are two important nonmotor symptoms of PD, exerting greater impacts on the quality of life (QOL).
(2) OSA is a condition characterized by the episodic cessation of breathing during sleep despite persistent ventilatory efforts, associated with sleep fragmentation
, arousals, and reductions in oxygen saturation.
According to principal investigator Jim Pagel, M.S., M.D., associate clinical professor at the University of Colorado Medical School system and director of the Sleep Disorders Center of Southern Colorado in Pueblo, the decline in frequency of nightmare recall may be attributed to the sleep fragmentation
that is caused by OSA.
Anecdotally, this physiologic disorder of sleep respiration seems to play an undetermined role in the nightmaring process, perhaps through the effects of chronic sleep fragmentation
and resultant sleep deprivation.
Triggers for Somnabulism, such as sleep fragmentation
and increased depth and/or duration of slow wave sleep, are also similar as that of other arousal disorders.