Rest-activity rhythm of the blind mole rat Spalax ehrenbergi under different lighting conditions

The mole rat is a solitary, subterranean and photoperiodic rodent. We investigated its rest activity behavior under several lighting conditions, complemented our observations with light-induced c-fos expression, and compared the activity behavior of two chromosomal forms (2n = 58 and 60). The 26 mole rats had a clear overall preference for activity in the light or dark period, but prolonged recordings in five individuals showed that the initial preference was not stable in the nocturnal animals, they became diurnal. A 6-h advance of the light-dark (LD) cycle induced a shift of activity and the previous LD preference was reestablished. The large daily variability of activity onset did not allow this study to determine whether the animals were entrained to the LD cycle upon release into constant darkness (DD) or whether activity had been masked by light. The period of the motor activity rhythm in DD free ran in more than 50% of the animals. No differences in activity were observed between the two karyotypes. Immunohistochemistry for c-fos expression in the nucleus suprachiasmaticus at different circadian times showed that c-fos was induced only in animals exposed to a 1-h light pulse during the subjective night, but not during the subjective day or in control animals in the absence of a light pulse. The large intra- and inter-individual variability in daily motor activity both in LD and in DD suggest only a weak photic entrainment of the circadian clock to light of approximately 100 lux, and possibly a weak regulation of behavior by the circadian clock.     

Twenty-four-hour ambulatory oxygen desaturation and electrocardiographic recording in obstructive sleep apnea syndrome

BACKGROUND: Although nocturnal pulseoximetry is routinely performed in obstructive sleep apnea syndrome (OSAS), pulseoximetry over a 24-h period has not been studied. HYPOTHESIS: The purpose of the study was to determine whether simultaneous 24-h oxygen desaturation and electrocardiographic (ECG) recording might be used to screen for daytime sleep sequelae in patients with OSAS. METHODS: Simultaneous recording of arterial oxygen saturation (SpO2) and ECG was conducted over a 24-h period in 18 male patients with OSAS (mean age 51.3 years) who were diagnosed by standard polysomnography (PSG), and in 15 age-matched healthy subjects (mean age 52.7 years) as controls to evaluate circadian variation of these parameters. The measures of heart rate variability (HRV) were calculated from 24-h ambulatory ECGs. Seventeen patients with OSAS showed excessive daytime sleepiness (EDS). We calculated the duration in which SpO2 decreased to < 90% (duration of SpO2 < 90%). The number of apnea/hypopneas per hour (AHI) during sleep was investigated with Apnomonitors (Chest MI, Co., Tokyo) on the same day as the SpO2 recordings. RESULTS: Controls showed no episodes of oxygen desaturation. In patients with OSAS, driving (33.3% of patients with OSAS) was the most common activity in which SpO2 decreased to < 90%, followed by daytime napping (27.8%) and resting after meals (22.2%). The duration of SpO2 < 90% over a 24-h period correlated significantly with the duration levels recorded during sleep (r = 0.99, p < 0.05) and in the afternoon (r = 0.62, p < 0.05), and with the AHI (r = 0.55, p < 0.05), but not with the duration of SpO2 < 90% in the morning. The number of ventricular premature beats correlated significantly with the duration of SpO2 < 90% for a 24-h period, but not with measures of HRV. Ventricular tachycardia was found in two (11.1%) and ST-T depression in three patients (16.6%) with underlying cardiac diseases. CONCLUSION: Our results suggest that daytime sleep attacks accompanied by oxygen desaturation in patients with moderate to severe OSAS may contribute to the occurrence of traffic or cardiovascular accidents. We conclude that 24-h ambulatory recordings of SpO2 and ECG are useful for screening for daytime sleep sequelae associated with the potential risk of this pathology in OSAS during social activities.     

Elevation of plasma cytokines in disorders of excessive daytime sleepiness: role of sleep disturbance and obesity

Excessive daytime sleepiness (EDS) and fatigue are frequent symptoms in the general population and the chief complaint of the majority of patients at Sleep Disorders Centers. There is evidence that the inflammatory cytokines tumor necrosis factor-alpha (TNF alpha), interleukin-1beta (IL-1beta), and IL-6 are involved in physiological sleep regulation and that their administration to humans is associated with sleepiness and fatigue. To explore whether plasma levels of TNF alpha, IL-1beta, and IL-6 are elevated in patients with EDS, we measured morning plasma levels of TNF alpha, IL-1beta, and IL-6 in 12 sleep apneics, 11 narcoleptics, 8 idiopathic hypersomniacs, and 10 normal controls. TNF alpha was significantly elevated in sleep apneics and narcoleptics compared to that in normal controls (P < 0.001 and P = 0.001, respectively). Plasma IL-1beta concentrations were not different between sleep disorder patients and controls, whereas IL-6 was markedly and significantly elevated in sleep apneics compared to that in normal controls (P = 0.028). The primary factor influencing TNF alpha values was the degree of nocturnal sleep disturbance, whereas the primary determinant for IL-6 levels was the body mass index. Our findings suggest that TNF alpha and IL-6 might play a significant role in mediating sleepiness and fatigue in disorders of EDS in humans.     

Increased prevalence of sleep disturbances and daytime sleepiness in subjects with bronchial asthma: a population study of young adults in three European countries

The aim of this study was to investigate whether asthma is associated with decreased quality of sleep and increased daytime sleepiness. The study involved a random population of 2,202 subjects supplemented by 459 subjects with suspected asthma, aged 20-45 yrs. The subjects were from Reykjavik (Iceland), Uppsala and G?teborg (Sweden) and Antwerp (Belgium), and participated in the European Community Respiratory Health Survey. The investigation included a structured interview, methacholine challenge, skinprick tests and a questionnaire on sleep disturbances. Participants in Iceland and Sweden also estimated their sleep times and made peak expiratory flow (PEF) recordings during a period of 1 week. Asthma was defined as self-reported physician-diagnosed asthma with current asthma-related symptoms (n = 267). Difficulties inducing sleep (DIS) and early morning awakenings (EMA) were about twice as common, and daytime sleepiness 50% more common, in asthmatics compared with subjects without asthma. After adjusting for possible confounders, a positive association was found between asthma and: DIS (odds ratio (OR) = 1.8); EMA (OR = 2.0); daytime sleepiness (OR = 1.6); snoring (OR = 1.7); and self reported apnoeas (OR = 3.7). Allergic rhinitis, which was reported by 71% of subjects with asthma, was independently related to DIS (OR = 2.0) and daytime sleepiness (OR = 1.3). A significant correlation was found between the number of asthma-related symptoms and sleep disturbances (p < 0.001). Asthma is associated with decreased subjective quality of sleep and increased daytime sleepiness. Concurrent allergic rhinitis may be an important underlying cause of sleep impairment in asthmatic patients.     

Development of cataplexy in genetically narcoleptic Dobermans

Forty-two genetically narcoleptic Doberman puppies [20 pure narcoleptic (N) puppies (from four narcoleptic x narcoleptic crosses) and 22 backcross narcoleptic (BN) puppies (from six narcoleptic x heterozygous crosses)] were systematically observed during the developmental period (4-24 weeks) to assess the age at onset and severity of cataplexy, a pathological manifestation of REM sleep atonia seen in narcolepsy. The mean age of onset of cataplexy was 9.69 +/- 1.15 weeks, with a median age of 7 weeks. The severity of cataplexy increased with age and reached a plateau at around 16-24 weeks. The effects of cross type (N vs BN) and sex on the development of cataplexy were analyzed. There was no difference in severity between N and BN puppies (P = 0.51). However, females had more severe cataplexy than males (P = 0.01), and this trend was preserved in five of the six litters that had both male and female puppies. These results suggest that the pathophysiological process in genetic canine narcolepsy emerges during the early developmental period and that it may involve a differential development in males and females. Furthermore, our results revealed that cataplexy onset corresponds to the emergence of adult-like REM sleep and to previously reported neuroanatomical and neurochemical abnormalities in canine narcolepsy.     

The alpha attenuation test: assessing excessive daytime sleepiness in narcolepsy-cataplexy

Daytime sleep tendency was assessed in 10 drug-free patients with narcolepsy-cataplexy and 10 normals matched for age and gender. Following nocturnal polysomnography, the alpha attenuation test (AAT) and the multiple sleep latency test (MSLT) were administered during five sessions occurring at 2-hour intervals beginning at 0900 and 1000 hours, respectively. For the AAT, participants were polysomnographically recorded for 8 minutes while seated in an illuminated room with their eyes alternately opened and closed. Power spectral analyses of electroencephalograph (EEG) activity at 02-A1 (10 second epochs) were calculated using fast Fourier transformations (FFT) within the alpha frequency range (8-12 Hz) to obtain ratios of mean eyes-closed to mean eyes-open alpha power (i.e. the alpha attenuation coefficient, AAC). The narcoleptics were sleepier than the normals as indicated by a significantly smaller mean AAC and a significantly shorter mean latency to stage 1 on the MSLT. These findings suggest that the AAT may provide a quick and practical objective assessment of the excessive daytime sleepiness (EDS) associated with narcolepsy.     

Cell adhesion molecules in vasculitis

Daytime sleepiness is a common complaint in blind subjects. Abnormally timed melatonin has been invoked as a possible cause of both daytime sleepiness and nighttime awakening. In free-running blind individuals, there is an opportunity to assess the relationship between endogenous melatonin rhythms and subjective sleepiness and naps. The aim of this study was to characterize melatonin rhythms and simultaneously to evaluate subjective napping. A total of 15 subjects with no conscious light perception (NPL) were studied for 1 month. Prior to the study, sleep disorders were assessed using the Pittsburgh Sleep Quality Index. Cosinor and regression analysis revealed that 9 of the 15 NPL subjects had free-running 6-sulphatoxymelatonin (aMT6s) rhythms (period [tau] range = 24.34 to 24.79 h), 3 were entrained with an abnormal phase, and 3 were normally entrained. Most of the subjects (13 of 15) had daytime naps; the 2 individuals who did not made conscious efforts not to do so. Subjects with abnormal aMT6s rhythms had more naps of a longer duration than did those with normal rhythms. Free-running nap rhythms occurred only in subjects with free-running aMT6s rhythms. The 2 abnormally entrained subjects who napped did so at times that coincided with high levels of aMT6s (mean aMT6s acrophase [phi] +/- SD = 14.30 +/- 1.08 h, 20.30 +/- 0.62 h; mean nap time +/- SD = 14.01 +/- 3.60 h, 18.23 +/- 3.20 h, respectively). Regardless of aMT6s rhythm abnormality, significantly more naps occurred with a 4-h period before and after the estimated aMT6s acrophase. In 4 free-running subjects, aMT6s acrophase (phi) passed through an entire 24-h period. When aMT6s was in a normal phase position (24:00 to 06:00 h), night-sleep duration tended to increase with a significant reduction in the number and duration of naps. Sleep onset and offset times tended to advance and delay as the aMT6s rhythms advanced and delayed. Our results show a striking relationship between the timing of daytime production of melatonin and the timing of daytime naps. This suggests that abnormally timed endogenous melatonin may induce sleepiness in blind subjects.     

Call for post-licensing human pharmacokinetic studies of administration of recombinant factor IX

Freeze-dried flowers of the Akinowasuregusa (Hemerocallis fulva L. var. sempervirona M. Hotta), a Hemerocallis genus of the lily family, were fed to C57BL strain mice. The slow wave sleep and paradoxical sleep of the Hemerocallis-treated group increased during the dark period. The differences between the control group and the Hemerocallis-treated group were significant (P < 0.05). The Hemerocallis feeding did not cause a change in sleep time during the light period. As a result, there was no significant change in the sleep-time percentage over a 24-h period.     

Tripartite hemolysin BL from Bacillus cereus. Hemolytic analysis of component interactions and a model for its characteristic paradoxical zone phenomenon

This study describes the use of the microdialysis technique to elucidate specific properties of the circadian pacemaking system in the hypothalamus, by measurement of melatonin production in the pineal gland. Melatonin has appeared to be a reliable marker of the pacemaker activity, which is influenced by the light/dark cycle. A phase shift in the light/dark cycle was applied to perturb the rhythm generating system. An 8-h phase advance resulted in the disappearance of melatonin production over two days, with basal levels comparable to normal daytime levels. In the subsequent return of rhythmic melatonin production, new clock characteristics could be revealed, due to the high time-resolution measurements of microdialysis. While half of the animals still did not show any rhythmicity, the other half of the animals regained rhythmicity with entrained onset of melatonin production, while the offset was variable and not stably entrained to lights on. Ten days after the shift, the system had completely recovered and all animals regained normal rhythmicity, in phase with the new light/dark cycle. The results are interpreted in terms of the two-oscillator model, with one oscillator reacting with a phase advance and the other with a phase delay to adapt to the phase shift.     

How sleep and mental disorders are related to complaints of daytime sleepiness

BACKGROUND: Daytime sleepiness is widespread and has negative impacts on the public sector. OBJECTIVE: To ascertain the incidence and prevalence of daytime sleepiness and associated risk factors in the general population. METHOD: In 1994, a representative sample of the non-institutionalized British population aged 15 years or older was interviewed via telephone using an expert computer-assisted program designed to facilitate surveys of this type (Sleep-Eval, M. M. Ohayon, Montreal, Quebec). Subjects were classified into 3 groups based on the severity of their daytime sleepiness. We completed 4972 interviews (acceptance rate, 79.6%). RESULTS: Severe daytime sleepiness was reported in 5.5% (95% confidence interval, 4.9%-6.1%) of the sample, and moderate daytime sleepiness in another 15.2% (95% confidence interval, 14.2%-16.2%). Associated factors with severe daytime sleepiness included female sex, middle age, napping, insomnia symptoms, high daily caffeine consumption, breathing pauses or leg pain in sleep, depressive disorder (based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria), falling asleep while reading or watching television, and motor vehicle crashes or accidents involving use of machinery. Moderate daytime sleepiness was associated with female sex, napping, insomnia symptoms, arthritis or heart disease, and gross motor movements during sleep. CONCLUSIONS: It is likely that daytime sleepiness deleteriously affects work activities, social and/or marital life, and exhibits a negative socioeconomic impact. In addition, the risk of a motor vehicle crash appears to be higher in this specific population: twice as many subjects operating a motor vehicle or using machine tools reported having a crash or accident, respectively, in the previous year in the groups with severe daytime sleepiness or moderate daytime sleepiness than did the general population with no daytime sleepiness. The high prevalence rates of daytime sleepiness and multiplicity of related factors mandate further scrutiny by public health officials.     

Child sleep disorders: Associations with parental sleep duration and daytime sleepiness.

This study examined the associations between childhood sleep disorders and mothers' and fathers' sleep duration and daytime sleepiness. One hundred seven families of children (ages 2-12 years) presenting to a pediatric sleep disorders clinic completed questionnaires assessing the sleep symptoms of the mother, father, and child. Parents of children with more than 1 type of sleep disorder experienced more daytime sleepiness than parents of children with a single sleep disorder. The pattern of results suggested more associations between maternal and child sleep than between paternal and child sleep. Within families, mothers reported significantly more daytime sleepiness than fathers, although there were no parental differences in sleep duration. Results provide preliminary evidence for an association between child sleep problems and parental daytime sleepiness, which may, in turn, extend previous research linking young children's sleep problems and parental functioning. Implications for treatment of both children and adults with sleep problems are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Treating arousals during sleep using behavioral self-management.

Found that self-management training was associated with increased sleep efficiency, reduced number of arousals and minutes awake after sleep onset during the 1st 3rd of the night, reported improvements in the sleep quality, and less daytime sleepiness for a 58-yr-old female S. These effects were documented using laboratory and home sleep recordings and self-reports over a 5-yr period. The results suggest 2 important leads for the further development of strategies for treating the complaint of insomnia. First, multicomponent strategies to modify a variety of daytime and nighttime variables based on individual behavioral analyses may be needed. Second, maintaining improvement in sleep and daytime behavior may require that clients learn problem-solving and self-management skills, with an emphasis on experiencing a greater sense of control over factors related to good and poor sleep. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characteristics of apneas and hypopneas during sleep and relation to excessive daytime sleepiness

STUDY OBJECTIVES: One of the most important symptoms in patients evaluated for possible obstructive sleep apnea syndrome is excessive daytime sleepiness, but the measures of apnea severity and of sleepiness used most commonly have not generally shown strong associations. We explored whether information recorded during standard polysomnography, other than the overall rate of apneas and hypopneas per hour of sleep (AHI), might help explain the measured severity of sleepiness. DESIGN: Observational SETTING: A clinical sleep laboratory in a university hospital PATIENTS: N = 1,146 patients evaluated for suspected sleep-disordered breathing with nocturnal polysomnograms and multiple sleep latency tests. RESULTS: The AHI during supine sleep (recorded in a subgroup of n = 169 subjects), the rate of apneas (n = 1,146), and the rate of obstructive apneas (n = 1,146) were particularly useful in explaining variation in measured levels sleepiness; rates of hypopneas and central apneas were less useful (n = 1,146). In addition, the minimum recorded oxygen saturation (n = 1,097) was as important as the AHI to the level of sleepiness. CONCLUSIONS: In an attempt to explain excessive daytime sleepiness among patients evaluated for sleep-disordered breathing, additional insight is provided by observation of supine sleep during polysomnography, by emphasis on apneas rather than hypopneas, by emphasis on obstructive rather than central events, and by consideration of the minimum oxygen saturation.     

Huntington''s disease gene product, huntingtin, associates with microtubules in vitro

The influence of CGP 35348 (a GABA(B) receptor antagonist) on the sleep-waking cycle was studied in rats. The animals were injected i.p. at the beginning of the light period and the data expressed by 2-h periods and total duration (6 h). At 100 mg/kg, slow-wave sleep (SWS) was decreased during the 6-h recording with a peculiar decrease during the first 2 h. SWS was subdivided into three stages: slow-waves; spindles occurring as SWS deepens; and intermediate stage appearing prior to paradoxical sleep (PS). Only the slow-wave stage and intermediate stage were decreased. Waking was increased during the 6-h recording. It was subdivided into waking with hippocampal theta rhythm (psychomotor active waking) and waking without theta activity (quiet waking). Both were increased during the first 2 h. However, quiet waking was increased throughout the recording duration. At 300 mg/kg, SWS was decreased during the three 2-h periods. This decrease was principally related to a decrease of the slow-wave stage. PS was increased over the 6-h recording with a marked increase during the second 2-h period. Consequently, under the influence of the GABA(B) receptor antagonist, the SWS was decreased at the expense of behavioral stages with cortical low-voltage activity (waking and PS). GABAergic neurons are present in the mesopontine structures responsible for these two stages. We can conclude that endogenous GABA acting at the GABA(B) receptor level participates in the regulation of waking and PS.     

Sleep and the menstrual cycle.

To evaluate changes in sleep across the phases of the menstrual cycle, sleep-wake diaries were completed by 32 healthy women twice daily for 2 menstrual cycles. There was a significant increase in sleep onset latency and a significant decrease in sleep efficiency and sleep quality during the luteal phase. This increase in sleep disturbance was observed in the entire sample and was not related to the severity of other premenstrual symptoms. However, women having increased severity of other premenstrual symptoms reported greater luteal increase in daytime sleepiness. Thus, although menstruating women are likely to show increased sleep disturbance during the luteal phase, those with other, more severe premenstrual symptoms are more likely to experience a luteal increase in daytime sleepiness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessment of family carers

Thirty-four patients who presented with excessive daytime sleepiness (EDS) and who showed an elevated number of periodic leg movements during sleep (PLMS) were studied. None of these patients reported other symptoms or presented sleep laboratory manifestations of narcolepsy or of breathing disorders during sleep. A diagnosis of restless leg syndrome, head trauma or a past history of psychopathology or infectious diseases known to cause EDS were also ruled out. In addition, none of the patients reported a history of drug or alcohol abuse, chronic sleep deprivation or irregular sleep-wake schedule and none were taking medications known to influence sleep at the time of the study. Results of the present study showed no correlation between PLMS index and poor sleep efficiency or daytime sleepiness as measured by the multiple sleep latency test (MSLT). However, a significant negative correlation was found between sleep efficiency at night and the mean sleep latency on the MSLT. These results suggest not only that PLMS and nocturnal sleep disruption are not the primary cause of EDS, but that these sleepy patients have a high propensity to sleep both at night and during the daytime. Therefore, the presence of PLMS during nocturnal sleep recording should not preclude the diagnosis of idiopathic hypersomnia.     

Ultradian and diurnal cyclicity in the sleep states of newborn infants during the first two postnatal days

OBJECTIVE: The purpose of this study was to investigate both ultradian and diurnal cyclicity in the sleep states of newborn fullterm infants during the first 2 postnatal days. METHODS: The sleep of 31 healthy newborn infants was recorded continuously throughout the first 2 postnatal days, starting immediately after birth, using an automated Motility Monitoring System (MMS). The MMS consists of a pressure sensitive mattress pad connected to an amplifier and a small 24-h analog recorder. A single channel of analog signals produced by the infant's respiration and body movements was recorded and then scored in 30-s epochs for Active Sleep. Quiet Sleep, Active-Quiet Transition, Sleep-Wake Transition, and Wake. DATA ANALYSES: The 48 h of recording were divided into successive 12-h periods from 07:00 h to 19:00 h (day) and 19:00 h to 07:00 h (night), and all measures were derived for each day and night period. Both cross-sectional and repeated measures analyses were used because all babies were not represented in all day/night periods. RESULTS: Day/night differences in state variables: On both days, there was greater Wakefulness, shorter Quiet Sleep Bout Lengths, shorter Mean Sleep Periods and shorter Longest Sleep Periods during the daytime. On day 1 only, there was less Quiet Sleep, shorter Quiet Sleep Bout Lengths and more Sleep-Wake Transition during the daytime. On day 2, repeated measures analyses revealed two additional day/night differences: less Quiet Sleep and more Sleep-Wake Transition during the daytime. Day/night differences in Quiet Sleep cyclicity: 28 sleep periods met the criteria for analysis of Quiet Sleep cyclicity, and only six of these occurred during the daytime. Seventeen of 28 analyzable sleep periods showed significant Quiet Sleep cyclicity. Only two of these occurred during the daytime. CONCLUSIONS: Contrary to the prevailing view of developing sleep rhythms, the results of this study suggest that newborn infants exhibit both ultradian ad diurnal cyclicity in their sleep patterns from the earliest postnatal period.     

Corneal shape changes after pars plana vitrectomy

BACKGROUND: The modern practice of using artificial light to extend waking activities into the nighttime hours might be expected to precipitate or exacerbate bipolar illness, because it has been shown that modifying the timing and duration of sleep can induce mania in susceptible individuals. With this possibility in mind, we treated a patient with rapidly cycling bipolar illness by creating an environment that was likely to increase and to stabilize the number of hours that he slept each night. METHODS: We asked the patient to remain at bed rest in the dark for 14 hours each night (later this was gradually reduced to 10 hours). Over a period of several years, his clinical state was assessed with twice-daily self-ratings, once-weekly observer ratings, and continuous wrist motor activity recordings. Times of sleeping and waking were recorded with sleep logs, polygraphic recordings, and computer-based event recordings. RESULTS: The patient cycled rapidly between depression and mania and experienced marked fluctuations in the timing and duration of sleep when he slept according to his usual routine, but his sleep and mood stabilized when he adhered to a regimen of long nightly periods of enforced bed rest in the dark. CONCLUSIONS: Fostering sleep and stabilizing its timing by scheduling regular nightly periods of enforced bed rest in the dark may help to prevent mania and rapid cycling in bipolar patients.     

Unfair treatment is associated with poor sleep in African American and Caucasian adults: Pittsburgh SleepSCORE project.

Objective: To test the association between self-reported unfair treatment and objective and self-reported sleep characteristics in African American and Caucasian adults. Design: Cross-sectional study of 97 African American and 113 Caucasian middle-aged adults. Main Outcome Measures: Participants completed: (a) two-night in-home, polysomnography (PSG) sleep study, (b) sleep diaries and actigraph assessments across 9 days and nights, and (c) self-report measures of sleep quality in the past month, and daytime sleepiness in the past 2 weeks. Results: Greater unfair treatment was associated with reports of poorer self-reported sleep quality and greater daytime sleepiness, shorter sleep duration, and lower sleep efficiency as measured by actigraphy and PSG, and a smaller proportion of rapid eye movement (REM) sleep. Racial/ethnic differences were few. Exploratory analyses showed that nightly worry partially mediated the associations of unfair treatment with sleep quality, daytime sleepiness, sleep efficiency (actigraphy), and proportion of REM sleep. Conclusion: Perceptions of unfair treatment are associated with sleep disturbances in both African American and Caucasian adults. Future studies are needed to identify the pathways that account for the association between unfair treatment and sleep. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The effects of cocaine on mood and sleep in cocaine-dependent males.

The effects of cocaine use and withdrawal on mood and sleep were examined. Three cocaine-dependent men lived in an inpatient facility for approximately 4 weeks, which included an initial abstinence phase (8–10 days), a cocaine administration phase (5 days), and a 2nd abstinence phase (14–16 days). During the 2nd phase, cocaine was administered intranasally a few hours before bedtime. During the day, mood and daytime sleepiness were measured, and sleep was monitored each night. Cocaine produced typical changes in mood and blood pressure, and sleep was severely disrupted. Following Phase 2, there were no changes in mood that was indicative of an abstinence syndrome, although, initially, daytime sleepiness increased. After 2 weeks, sleep architecture remained different from age-matched controls. This study is the first to measure changes in sleep architecture polysomnographically following a period of controlled cocaine use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)