SLEEP

Toyohiko,, Satoh;Tatsuko,, Yokota;Shingo,, Kitayama

doi: 10.1093/sleep/14.1.2pmid: N/A

Summary: During slow-wave sleep, extracellular potassium ion activity in the dorsal hippocampus of the cat was comparable to that during quiet wakefulness. During rapid eye movement (REM) sleep, it showed a gradual increase by 0.2–0.3 mM in the CAl pyramidal layer and its close vicinity. No phasic increase was observed when REM bursts occurred. The enhanced K+ activity during REM sleep is considered to reflect the overall activity of the neurons in the pyramidal layer. Extracellular potassium ions, REM sleep, Hippocampus This content is only available as a PDF. © 1991 American Sleep Disorders Association

Edinger, Jack, D.;Marsh, Gail, R.;McCall, W., Vaughn;Erwin, C., William;Lininger, Anne, W.

doi: 10.1093/sleep/14.1.13pmid: N/A

Summary: Twenty patients with difficulties initiating and maintaining sleep (DIMS) were monitored in their homes for three consecutive nights using ambulatory polysomnography (PSG). Following each night of monitoring, patients provided subjective ratings of sleep disturbance and tolerance of the PSG equipment. Friedman analyses of variance performed on the objective and subjective parameters showed that the sample, as a whole, evidenced no systematic first night effects (FNE) in response to monitoring. Inspection of the data from each individual subject, nevertheless, showed that half of the sample did experience multiple FNE. Further, several scales from the Minnesota Multiphasic Personality Inventory discriminated those patients who showed multiple FNE from those who did not. However, far more striking was the finding that clinically and statistically significant intrasubject variability across nights was observed for each sleep parameter measured. Given this finding, a single ambulatory PSG study may not fully convey the nature of the sleep disturbance experienced by the DIMS patient even when FNE are absent. We, thus, recommend multiple ambulatory sleep studies for those clinical and research situations in which it is necessary to document patients' night-to-night sleep variability. In contrast, when the goal of the PSG study is that of determining a sleep diagnosis, a single ambulatory study, in combination with other clinical data, may be sufficient. DIMS, FINE, Sleep disturbance, PSG study, Older insomnia patients This content is only available as a PDF. © 1991 American Sleep Disorders Association

Bes,, F.;Schulz,, H.;Navelet,, Y.;Salzarulo,, P.

doi: 10.1093/sleep/14.1.5pmid: 1811320

Summary: This study describes the temporal distribution of slow-wave sleep (SWS) (defined as the visually scored stages 3 + 4) across the night for 16 infants aged between 20 weeks and 1 year, 17 children between I and 6 years, and 17 adults between 20 and 36 years. In all three groups the amounts of SWS peaked during the first nonrapid eye movement (NREM) episode. SWS decreased across the night for adults and children, but not for infants. In infants the amounts of SWS remained at a fairly constant level from the second cycle onward, although many cycles were observed with zero SWS. The latter was evident from the very low tendency for SWS to appear in consecutive NREM/REM cycles. Rather, SWS was observed in alternate cycles. In children this phenomenon was less prominent but still well visible, and the tendency for SWS to appear in consecutive cycles had increased. In adults SWS occurred predominantly in consecutive cycles. The results suggest that whereas REM recurrence time increases twofold from infancy to adulthood, SWS recurrence time remains of similar length in infants, children, and adults. Slow-wave sleep, Ontogeny, Sleep cycles This content is only available as a PDF. © 1991 Association of Professional Sleep Societies

Shaver, J. L., F.;Giblin,, E.;Paulsen,, V.

doi: 10.1093/sleep/14.1.18pmid: 1811314

Summary: Eighty-two midlife women (40-59 years) were classified as poor or good sleepers according to either self-reported sleep quality or a sleep efficiency index (SEI) criterion, for comparison of wakefulness, fragmentation and other somnographic sleep variables; as well as psychological (SCL-90) and somatic symptom distress, When classified solely by self-report, the good and poor sleeper groups did not differ on any somnographic variables but self-declared poor sleepers had higher psychological distress scores than good sleepers (p ≤ 0.01). When classified solely by the SEI criterion, the good and poor sleepers did not differ on psychological distress but, as expected, differed on various somnographic wakefulness as well as rapid eye movement and stage 2 sleep variables. Further analysis of four subgroups derived by combining objective and subjective, good and poor sleep scores indicated that 15% of this sample (n = 12) perceived but had no objective evidence of poor sleep, and this group scored highest in psychological distress. Only seven women perceived poor sleep in concert with demonstrating low SEL They scored highest in menopausal symptoms but not in general psychological distress. Women's sleep, Menopause, Psychological distress This content is only available as a PDF. © 1991 American Sleep Disorders Association

Libert, J., P.;Bach,, V.;Johnson, L., C.;Ehrhart,, J.;Wittersheim,, G.;Keller,, D.

doi: 10.1093/sleep/14.1.24pmid: 1811316

Summary: In a counter-balanced design, the effects of daytime and/or nighttime exposure to heat and/or traffic noise on night sleep were studied in eight healthy young men. During the day, the subjects were exposed to baseline condition (ambient temperature = 20°C; no noise) or to both heat (35°C) and noise. The duration of the daytime exposure was 8 h ending 5 h before sleep onset. The following nights, the subjects slept either in undisturbed (20°C; no noise) or in noise, heat, or noise plus heat-disturbed environments. During the day, the various types of traffic noise were distributed at a rate of 48/h with peak intensities ranging between 79 and 86 dB(A). The background noise level was at 45 dB(A). At night, the peak intensities were reduced by IS dB(A), the rate was diminished to 9/h, and the background noise was at 30 dB(A). Electrophysiological measures of sleep and esophageal and mean skin temperatures were continuously recorded. The results showed that both objective and subjective measures of sleep were more disturbed by heat than by noise. The thermal load had a larger impact on sleep quality than on sleep architecture. In the nocturnal hot condition, total sleep time decreased while duration of wakefulness, number of sleep stage changes, stage I episodes, number of awakenings, and transitions toward waking increased. An increase in the frequency of transient activation phases was also found in slow-wave sleep and in stage 2. In the nocturnal noise condition, only total number of sleep stage changes, changes to waking, and number of stage 1 episodes increased. Disturbed days followed by undisturbed nights only affected number of stage changes. The effect of heat and/or noise on sleep at night was not significantly enhanced by the presence of daytime disturbances. Heat, Noise, Sleep, EEG, Humans This content is only available as a PDF. © 1991 American Sleep Disorders Association

Tulen, Johanna H., M.;Man in 't Veld, Arie, J;Dzoljic, Michailo, R.;Karel,, Mechelse;Peter,, Moleman

doi: 10.1093/sleep/14.1.32pmid: 1811317

Summary: Sleep characteristics are presented for two female patients (aged 21 and 31 years) with central and peripheral dopamine beta-hydroxylase (DBH) deficiency. This deficiency results in the absence of norepinephrine, epinephrine, and their metabolites in plasma, urine, and cerebrospinal fluid, while concentrations of dopamine are increased. The sleep pattern of these patients was studied when they were untreated, after blockade of central dopamine receptors with metoclopramide, and after restoring norepinephrine production with D,L-threo-3,4-dihydroxyphenylserine (DOPS). When the patients were untreated sleep duration was normal, with tendencies of a decreased amount of rapid eye movement (REM) sleep, presence of alpha-delta sleep, and an increased amount of slow-wave sleep. The amount of REM sleep varied between 18 and 21 % of sleep period time. Administration of metoclopramide resulted in a slight reduction of REM sleep to 16-17%, whereas wakefulness after sleep onset increased. During treatment with DOPS, an increase in the amount of REM sleep was observed in both patients to an average amount of 27%. These data indicate that in patients with DBH deficiency norepinephrine is not essential for the development of a normal sleep/wake pattern but may have a facilitatory role in the generation of REM sleep. Dopamine beta-hydroxylase deficiency, Norepinephrine, Dopamine, D,L-Threo-3,4-dihydroxyphenylserine, Metoclopramide, Sleep This content is only available as a PDF. © 1991 American Sleep Disorders Association

Kahn,, A.;Rebuffat,, E.;Sottiaux,, M.;Dufour,, D.;Cadrane1,, S.;Reiterer,, F.

doi: 10.1093/sleep/14.1.39pmid: N/A

Abstract Summary: We investigated whether acid reflux in the proximal esophagus can induce arousal from sleep in infants. Fifty normal infants with occasional regurgitations were studied at the age of 8 weeks (range 4-26 weeks). In each child a pH probe was placed in the proximal portion of the thoracic esophagus, in front of the third vertebra, under radiologic control. Polygraphic monitoring of state of alertness and of proximal esophageal pH changes was recorded continuously during one night. The data were analyzed blind. For 41 of the 50 infants, a total of 97 drops below pH 4 was computed. Reflux was more frequently associated with wakefulness (41 % of the episodes), or rapid eye movement (REM) sleep (39%), than with non REM (19%) or indeterminate sleep (1 %). Comparing the fifth and the last minutes preceding the pH drops, a significant increase in the number of behavioral arousals was observed (p = 0.003). In comparison with the minute before the drop in esophageal pH, a further significant increase in the number of arousals occurred during the first minutes following the pH drop (p = 0.001). Although the first minutes following the 97 episodes of reflux represented only 0.4% of the total sleep time, 76% of all arousals (74 out of97) took place during this time period (p = 0.001). Five minutes after the pH drops, the behavioral changes tended to return to prereflux values. It is concluded that in infants, during sleep, proximal gastroesophageal reflux can act as a strong arousal stimulus. Key Words: Sleep-Arousal-Refiux-Gastroesophageal-Infant-Insomnia. Sleep, Refiux, Gastroesophageal, Infant, Insomnia This content is only available as a PDF. © 1991 American Sleep Disorders Association

Rosen, Raymond, C.;Kostis, John, B.;Seltzer, Lawrence, G.;Taska, Lynn, S.;Holzer, Barry, C.

doi: 10.1093/sleep/14.1.43pmid: 1687425

Summary: Although the effect of beta blockers on heart rate (HR) at rest, during exercise, and by ambulatory electrocardiography during the day and night has been studied extensively, data on the effect of these drugs on heart rate during the various stages of sleep are not available. We performed overnight polysomnography and exercise testing in a randomized, double-blind, placebo-controlled, Latin square crossover study of four beta blockers with different ancillary properties (atenolol 100 mg daily, metoprolol 100 mg, pindolol 10 mg, and propranolol 80 mg), on 30 healthy men aged 23-40 years (29.4 ± 4.3) (mean ± SD). At rest pindolol increased HR by 4.7 beats/min ± 13.1 (p < 0.05), while beta blockers without intrinsic sympathomimetic activity (ISA) decreased HR (p < 0.0001) by 6.1 ± 8.8 (atenolol), 5.8 ± 8.4 (propranolol), and 5.0 ± 9.4 (metoprolol). Exercise at 125 W increased HR on placebo by 76.4 ± 18.4 beats. Compared to placebo all beta blockers were associated with lower (p < 0.0001) exercise HR by 18.3 ± 23.2 atenolol, 21.1 ± 15.5 metoprolol, 16.8 ± 14.1 pindolol, ad 20.8 ± 13.1 propranolol [not significant (NS) among beta blockers). Thus the effect of beta blockers on heart rate was magnified during exercise. Mean and maximum HR were higher in rapid eye movement (REM) than in nonREM (NREM) sleep (p < 0.001). However, the effects of beta blockers on NREM and REM sleep were almost identical (atenolol 7.3 ± 5.9 decline during NREM and 7.4 ± 5.7 during REM, metoprolol 7.7 ± 6.5 NREM and 8.0 ± 6.0 REM, propranolol 6.7 ± 5.7 NREM and 6.8 ± 6.1 REM). A differential effect of pin dolo I on NREM/REM sleep analogous to rest! exercise was not observed (increase by 7.5 ± 9.3 in NREM and by 10.1 ± 8.6 in REM) (p = NS). In addition, an increase of HR in the early morning hours was not observed as long as the subjects remained asleep. These data suggest that: I) the tachycardia of REM sleep is mediated primarily through nonadrenergic (e.g., vagal) mechanisms, and 2) the increase in HR during early morning hours is probably due to awakening and the assumption of erect position. These findings may be clinically relevant in view of the circadian variation of ischemic morbid and mortal events. Sleep, Heart rate, Beta blockers This content is only available as a PDF. © 1991 American Sleep Disorders Association

, Van Gelder, Russell N.;Edgar, Dale, M.;Dement, William, C.

doi: 10.1093/sleep/14.1.48pmid: 1811319

Summary: Long-term circadian studies of sleep and wakefulness in rodents have been hindered by the labor required to analyze long polygraph records. To expedite such studies, we have designed and implemented SCORE, a microcomputer-based real-time sleep scoring system for rodents. The electroencephalograph is digitized in 10-s epochs at 100 Hz. Frequency and amplitude information from the waveform are extracted into a 48-dimension vector that is then compared to previously taught vectors representing the canonical features of four arousal states: wakefulness, theta-dominated wakefulness, rapid eye movement (REM) sleep, and nonREM (NREM) sleep. Match values are assigned for each state to each epoch; aft(:r excluding states based on wheel-running or drinking activity data, the nonexcluded state with the best match value for the epoch is scored. Analysis of over 23,000 epochs for four mice yielded an overall agreement of 94.0% b(:tween two human scorers and the program, compared with a 94.5% agreement between the two human scorers. The SCORE algorithm matched the human concensus best for wakefulness (97.8%) and NREM sleep (94.7%), but was lower for REM sleep (75.2%) and theta-dominated wakefulness (83.3%). Most errors in scoring of REM sleep were in close temporal proximity to human-scored REM epochs. SCORE is capable of scoring arousal states for eight animals simultaneously in real time on a standard IBM PC equipped with a commercially available analog-to-digital conversion board, and should considerably facilitate the performance of long-term studies of sleep and wakefulness in the rodent. Mus musculus, Computer, Circadian rhythm, Sleep-wake, On-line This content is only available as a PDF. © 1991 American Sleep Disorders Association

Acebo,, Christine;Watson, Robert, K.;Bakos,, Linda;Thoman, Evelyn, B.

doi: 10.1093/sleep/14.1.56pmid: 1811321

Summary: Two studies investigated the reliability and validity of measures of sleep and apnea using the home sleep monitoring system (HMS), which requires no instrumentation of the subject. From a pressure-sensitive pad on the subject's bed, signals from respiration and motility are recorded. These are scored for sleep and the occurrence of apneas, and the following measures are obtained: time in bed, total sleep time, number of awakenings from sleep, waking after sleep onset, sleep efficiency, and number of apneas. Overnight recordings of 14 adults were made concurrently with polysomnographic recordings in the New Haven Sleep Disorders Center. Significant agreement was found for each sleep measure and the apnea index. Four weekly 24-h recordings were made of eight elderly women, aged 62 to 90, in the home. There were significant individual differences and measurement reliability for each sleep measure and number of apneas. Some or the elderly showed highly episodic sleep patterns; and three of them showed high and variable apneas over the four weeks. These studies indicate the potential of the HMS for characterizing sleep in the elderly from nonintrusive, naturalistic observations in the home. Sleep, Apnea, Elderly, Home monitoring system This content is only available as a PDF. © 1991 American Sleep Disorders Association