Showing papers on "Rapid eye movement sleep published in 1988"

Medullary regions mediating atonia

Abstract: Electrical stimulation studies have implicated the medial medulla in the inhibition of muscle tone. In the present report we present evidence for suppression of muscle tone by chemical activation of the medial medulla. We find 2 distinct zones within the classically defined medial medullary inhibitory area. A rostral region corresponding to the nucleus magnocellularis (NMC) is sensitive to glutamate. Atonia produced by activation of this region is mediated by non-NMDA receptors. A caudal region, corresponding to the nucleus paramedianus (NPM) is sensitive to ACh. Atonia produced by activation of this region is mediated by muscarinic receptors. Activation of these regions both in acute decerebrate and intact cats suppresses muscle tone. We find that the cholinoceptive dorsolateral pontine region, previously implicated in atonia control, can be activated by glutamate-sensitive non-NMDA receptors. Microinjection of atropine into the NPM or of glutamylglycine into the NMC blocks atonia elicited by pontine carbachol injection. The medullary regions identified here are hypothesized to mediate the suppression of muscle tone that occurs in rapid eye movement sleep and in cataplexy and may have a role in postural control in waking.

Growth hormone-releasing factor enhances sleep in rats and rabbits

Abstract: Previously, it was suggested that a hypothalamic mechanism links somatotropin [growth hormone (GH)] secretion to sleep regulation, and this may explain the temporal correlation between GH release and nonrapid eye movement sleep (NREMS) on sleep onset. The purpose of these experiments was to study whether growth hormone-releasing factor (GRF), a hypothalamic peptide responsible for stimulation of GH secretion, also has the capacity to promote sleep in rats and rabbits. Artificial cerebrospinal fluid or GRF (human GRF-[1-40], 0.01, 0.1, and 1 nmol/kg) was intracerebroventricularly injected to rats at dark onset, and the electroencephalogram (EEG), brain temperature (Tbr), and motor activity were recorded for 24 h. Rabbits received the same doses of GRF during the light period, and sleep-wake activity was monitored for 6 h. GRF promoted NREMS and rapid eye movement sleep (REMS) and increased EEG slow-wave activity in both rats and rabbits. NREMS increased in postinjection hour 1 after low doses of GRF, whereas the effect was more prolonged after higher doses. REMS increased in response to the low and middle doses of GRF in postinjection hour 1 in rats and in hour 2 after each dose in rabbits. The diurnal rhythms of sleep-wake activity, motor activity, and Tbr were not affected in rats. Because GRF promotes sleep and also stimulates GH secretion, it is a likely candidate for linking GH secretion and sleep regulation.

Breathing Pattern and Eye Movement Density during REM Sleep in Humans

Abstract: Changes in the density of eye movement during rapid eye movement (REM) sleep are associated with changes in ventilation and ventilatory response in animals. Recent data in patients with chronic obstructive pulmonary disease suggest that periods of frequent eye movements may be associated with hypoxemia during REM sleep. We have therefore investigated the association between eye movements and ventilation and ventilatory pattern in 10 normal men. Expired ventilation was measured using a pneumotachograph attached to a valved face mask with a dead space of 50 ml and incorporating a peripheral CO2 leak detector. Ventilation was reduced (p less than 0.02) in all stages of sleep compared with that during wakefulness, with no difference between the level of ventilation in each sleep stage (awake, 7.18 +/- 0.43 SEM; Stage 2, 6.47 +/- 0.43; Stage 3/4, 6.45 +/- 0.52; REM sleep, 6.55 +/- 0.47 L/min). During REM sleep, eye movements (EMs) were associated with rapid shallow breathing. Dividing REM into 20-s epochs with or without EMs, EMs were associated with a raised breathing frequency (no EMs, 14.4 +/- 0.4 breaths/min; EMs, 15.8 +/- 0.5 breaths/min; p = 0.01), reduced tidal volume (0.49 +/- 0.03 L; 0.41 +/- 0.03 L; p less than 0.01), and reduced minute ventilation (6.87 +/- 0.45 L; 6.27 +/- 0.51 L; p = 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Passive body heating and sleep: influence of proximity to sleep

Abstract: Previous studies have found enhanced delta sleep following body heating. This study assessed the influence of body heating as a function of its proximity to sleep. Electroencephalogram (EEG) sleep patterns were compared following body heating (1 h immersion in water at 41 degrees C) at each of four times of day: morning (MO), afternoon (AF), early evening (EE), and late evening (LE), ending just prior to sleep. A delta filter/integrator system provided objective measures of delta content. Relative to baseline nights, whole-night delta sleep was increased by the two evening heating sessions only, particularly LE heating. Following LE, the increased delta occurred primarily in the first sleep cycle, whereas EE heating elicited increased delta distributed across the later sleep cycles (cycles 2-4). Effects on manually staged indices of slow wave sleep (SWS) were confined to increases in Stage 4 in the first sleep cycle following LE heating. Heating just prior to sleep also resulted in a substantial reduction in the duration of the first rapid eye movement sleep period. Sleep onset time was reduced by heating, particularly EE heating. The results indicate that body heating induces temporary changes that affect sleep propensity and both the quantity and temporal distribution of delta activity in the sleep EEG.

Sleep and EEG spectra in the pigeon (Columba livia) under baseline conditions and after sleep deprivation

Abstract: Sleep in adult domestic pigeons was studied by continuous 24-h recording of the EEG, EMG and EOG. Vigilance states were scored on the basis of behavioral observations, visual scoring of the polygraph records, and EEG power spectra. The animals showed a clear nocturnal preference for sleep. Throughout the dark period, EEG slow-wave activity was at a uniform level, whereas REM sleep (REMS) showed an increasing trend. EEG power density values differed significantly between the vigilance states. In general the values were highest in nonREM sleep (NREMS), intermediate in waking (W) and lowest in REMS. Twenty-four hour sleep deprivation reduced W and increased REMS, effects that are well documented in mammals. Unlike in mammals, EEG slow-wave activity remained unchanged, whereas EOG activity in W and NREMS was enhanced.

The timing and duration of sleep in partial sleep deprivation therapy of depression.

Abstract: — The antidepressant response to partial sleep deprivation early in the night (PSD-E) was compared with the response to partial sleep deprivation late in the night (PSD-L) in 16 drug-free depressed inpatients using a balanced order crossover design. PSD-L had a significantly greater antidepressant effect that PSD-E. The response to PSD-L was sustained and enhanced by a second night of treatment. Patients had significantly shorter sleep durations and reduced REM sleep on PSD-L that did not occur in the PSD-E situation. There was a significant negative correlation between response to PSD and sleep duration, and in particular, REM sleep duration, in the late sleep deprivation situation. Thus, the amount and timing of sleep appear to be factors in the response to PSD, but additional studies are needed to evaluate the relative importance of these parameters.

Low-Frequency Oscillations of Cortical Oxidative Metabolism in Waking and Sleep

Abstract: To study the changes in cortical oxidative metabolism and blood volume during behavioral state transitions, we employed reflectance spectrophotometry of the cortical cytochrome c oxidase (cyt aa3) redox state and blood volume in unanesthetized cats implanted with bilateral cortical windows and EEG electrodes. Continuous oscillations in the redox state and blood volume (∼9/min) were observed during waking and sleep. These primarily metabolic oscillations of relatively high amplitude were usually synchronous in homotopic cortical areas, and persisted during barbiturate-induced electrocortical silence. Their mean amplitude and frequency did not vary across different behavioral/EEG states, although the mean levels of cyt aa3 oxidation and blood volume during rapid eye movement (REM) sleep significantly exceeded those during waking and slow-wave sleep. These data suggest the existence of a spontaneously oscillating metabolic phenomenon in cortex that is not directly related to neuroelectric activity. A superim...

REM sleep behavioral disorders.

Abstract: REM sleep behaviors were recently described as wild, dream-enacting behaviors during REM sleep with loss of usual atonia on submental muscles. We examined 6 patients (5 M, 1F) with characteristic episodes of behavioral manifestations during REM sleep. Polysomnographic data indicate a decrease in first REM latency, an absence of stage 4 NREM, altered phasic motor activity and behavioral episodes during REM sleep even with normal chin muscle atonia. Three patients had Shy-Drager syndrome, 1 olivopontocerebellar atrophy and 2 patients had no neurological disease. The crucial importance of a disinhibited locomotor system during sleep appears to be responsible for this REM parasomnia.

Narcolepsy in a Pediatric Population

Abstract: • Narcolepsy, a sleep-wake disorder of unknown cause, has been reported as occurring in the pediatric population, but only two reports of cases in the literature have included polysomnographic data on children with narcolepsy. We compared the clinical and polysomnographic data on a series of eight patients 15 years of age or younger and an adult comparison group with narcolepsy. All patients presented with excessive daytime sleepiness, and no significant difference was found between groups for the incidence of cataplexy, hypnagogic hallucinations, and sleep paralysis. On polysomnographic evaluation the pediatric group had increased total sleep time, percent-stage 3/4 sleep, percent rapid eye movement sleep, and decreased stage 1 sleep, which all are expected age-related differences. The pediatric group also showed a greater degree of daytime sleepiness and an increased frequency of sleep-onset rapid eye movement periods. While pediatric patients with narcolepsy resemble adults in their mode of presentation and the incidence of accessory symptoms, the increase in severity of sleepiness highlights the importance of diagnosing narcolepsy in children as early as possible so that treatment can be initiated. ( AJDC 1988;142:210-213)

Animal depression model by neonatal clomipramine: reduction of shock induced aggression.

Abstract: Clomipramine, administered to neonatal rats, has been reported to produce adult behavioral and REM sleep abnormalities. They include decreased sexual behavior, increased ambulation in the outer part of an open-field arena, increased REM sleep % of total sleep time, and in descriptive data, short REM latency, and increased REM phasic events. Since these abnormalities resemble some found in human endogenous depression, we have hypothesized that the adult rats represent an animal model of depression. Diminished aggressive behavior is a common characteristic of endogenous depression. This study tested the validity of the animal depression model by determining in rats the effect of neonatal clomipramine on adult shock-induced fighting. Experimental rats were treated neonatally with clomipramine and control rats were treated neonatally with saline. When they matured, compared with control rats, experimental rats had significantly fewer offensive fighting responses, and significantly more defensive fighting responses. The findings add some support to the validity of the animal depression model produced by neonatal clomipramine.

Influence of the Cholinergic Agonist RS 86 on normal sleep: Sex and age effects

Abstract: In 36 healthy control subjects (21 females, 15 males; age range 18-65 years; mean age 41.8 years, SD 15.6 years), a bedtime dose of 1.5 mg RS 86, an orally acting cholinergic agonist, shortened rapid eye movement (REM) latency, increased REM sleep, and decreased slow-wave sleep. Six of the subjects (greater than 40 years old) even displayed sleep-onset REM periods after the drug. Results of the present study agree well with those of studies using other cholinomimetics (i.e., physostigmine, arecholine) and confirm the importance of the cholinergic system for REM sleep regulation. Since RS 86 mimicked some of the REM sleep abnormalities specific for patients with depressive disorders, the cholinergic system may play a role in the pathogenesis and pathophysiology of depressive diseases.

Increase of paradoxical sleep induced by microinjections of ibotenic acid into the ventrolateral part of the posterior hypothalamus in the cat.

Abstract: In order to study putative hypothalamic mechanisms of sleep-waking cycle regulation we injected a neural cell body toxin--ibotenic acid (IBO), 40 to 200 micrograms--into the ventrolateral part of the posterior hypothalamus (HVL). This injection induced a dramatic biphasic and transient hypersomnia immediately after the disappearance of the anesthesia (14 to 24 hours after the injection). The duration of hypersomnia was dose dependent. Its first period was characterized by an increase in paradoxical sleep (PS) (300%). Then, during the second phase, PS disappeared and there was a subsequent increase of slow sleep (SWS) (60%). Finally, on the third day, all cats recovered control level of PS and SWS while, 3 weeks later, the histological analysis revealed the great loss of cell bodies in the HVL in all cats.

Sleep and hypometabolism

Abstract: Metabolic rate (MR) of endotherms is lower during sleep than quiet wakefulness (W), largely as a result of a regulated lowering of body temperature (Tb) during slow-wave sleep (SWS). In mammals this decrease in regulated Tb is evidenced by a lowered hypothalamic thermosensitivity. In avian thermoregulatory systems spinal thermosensitivity is lower in SWS than in W. In rapid eye movement sleep (REMS) there is a severe inhibition of the thermoregulatory systems. Hypothalamic cells that are thermosensitive during W become less so during SWS and become totally insensitive to temperature during REMS. The adjustments in thermoregulatory systems of endotherms that result in lower Tb and MR during SWS have been shaped by natural selection in different species to produce a variety of adaptations for energy conservation. Bouts of torpor, hibernation, or nocturnal hypothermia consist mostly of SWS, and these states involve a downward resetting of hypothalamic thermosensitivity in mammals and spinal thermosensitivity...

Cardiovascular and respiratory relationships with neuronal discharge in the central nucleus of the amygdala during sleep-waking states.

Abstract: We examined state-related relationships of neuronal discharge in the central nucleus of the amygdala (ACE) with cardiac and respiratory patterning. ACE cell discharges correlated with cardiac and respiratory timing, arterial pressure, and several respiratory parameters in undrugged, freely moving cats during waking, quiet sleep, and rapid eye movement sleep. Phasic discharge with the cardiac or respiratory cycle was examined using cross-correlation histograms. Of 80 cells in 8 cats, 24% showed a timing relationship with the cardiac or respiratory cycle, i.e., a tendency to discharge with each cardiac R-wave or with each breath, 12% with the cardiac cycle, and 14% with the respiratory cycle (2 cells showed both). All timing relationships were state dependent, usually observed in only one sleep-waking state per cell. Over half the cells showed a significant Pearson's r rate correlation with respiratory period or arterial pressure. Two-thirds of the cells showing arterial pressure correlations also correlated with respiratory period. A substantial proportion of ACE cells thus shows a state-dependent modulation of discharge rate and pattern by cardiovascular and respiratory variables. Rate and timing relationships were mutually exclusive within states, suggesting a state-dependent functional differentiation within the ACE.

REM sleep in humans begins during decreased secretory activity of the anterior pituitary

Abstract: The purpose of this study was to define the temporal relationship between anterior pituitary hormone profiles and rapid-eye-movement (REM) sleep occurrence. Plasma levels of prolactin (PRL), adrenocorticotropic hormone (ACTH), luteotropin (LH), thyroid-stimulating hormone (TSH) and growth hormone (GH) were measured in 10 min blood samples. Analysis of the nocturnal profiles for these hormones and the concomitant patterns of sleep stage distribution indicate that the onset of REM sleep very seldom occurred during the increasing phase of secretory episodes. In 93-98% of cases, depending on the hormone studied, it occurred either during the declining phase, at peak level, or at nadir, each of these phases reflecting a decrease in glandular activity. This relationship differed from the very close association previously found between the sleep stage alternation and plasma renin activity. These findings seem to fit in with the concept of reduced sympathetic activity and disruption of the vegetative functions during REM sleep.

Rapid eye movement sleep state detector

Abstract: A method and apparatus are provided in which an REM sleep state is accurately identified by detecting and counting a selectable number of eye movements within a selectable time interval. A body movement sensor is used to prevent false indications of REM sleep by inhibiting such indication upon sensing of body movement. An eye movement sensor which uses IR light transmission across an eye is disclosed.

Effect of Maturation on Heart Rate Response to Ocular Compression Test during Rapid Eye Movement Sleep in Human Infants

Abstract: Thirty-three premature and full-term infants (31.5-50 wk postconceptional age) free from neurologic and cardiopulmonary disease at time of testing, underwent a standardized ocular compression test during polygraphically controlled rapid eye movement sleep. RR intervals were measured on the ECG before and during ocular compression. RR interval changes during ocular compression were compared to the preceding 60-s mean RR interval in each infant. Results were analyzed relative to gestational age, postnatal age, and postconceptional age. Baseline heart rate during REM sleep decreased with postconceptional age. During ocular compression, there was a significant negative correlation between the longest RR interval or the "latency" variable with postconceptional age. Latency is defined as the time, in milliseconds, from beginning of eyelid pressure to the first measurable RR increase compared to mean control RR + 1 SD. Our results indicate that during rapid eye movement sleep, "baseline heart rate" decreases with maturation, an effect supposedly related to increased vagal activity, whereas the heart rate response on ocular pressure stimulus, a vagally mediated reflex, is significantly influenced and blunted with maturation.

Effects of clomipramine on sleep EEG and nocturnal penile tumescence: a long-term study in a healthy man.

Abstract: The effects of the tricyclic antidepressant clomipramine on sleep EEG and nocturnal penile tumescence (NPT) were investigated during a long-term study in a normal male control subject. During 21 consecutive days the subject received first placebo for 3 days, then stepwise increasing dosages of clomipramine for 10 days, and finally placebo after withdrawal for 8 days. Under clomipramine, rapid eye movement (REM) sleep was suppressed markedly; an REM rebound occurred after withdrawal. Awake and stages 1 and 2 increased while slow wave sleep was diminished under clomipramine. Those non-REM parameters returned to baseline values after drug cessation. NPT was reduced simultaneously with REM sleep under clomipramine 30 to 75 mg. Under this dosage range, full erections occurred during the later hours of sleep in association with the delayed REM periods. Clomipramine 100 mg prompted a further decrease of NPT, which exceeded the REM suppression. Most of the changes and NPT parameters depended significantly on the dosage and the plasma concentration of clomipramine. After withdrawal, NPT needed 6 days to normalize. Although NPT was disturbed distinctly, no erectile dysfunction, but a decrease of sexual interest and, once, a lack of ejaculation, were reported.