Morning Alertness Research Articles

Sleep Behavior of South African Adolescents

To survey a large group of South African adolescents about their sleep behavior, daytime behaviors, and morning alertness as compared to those of other teenagers worldwide. Subjects completed a questionnaire about their sleep habits and daytime behaviors on the previous day, and subjective morning alertness at the time of completing the questionnaire. Four secondary schools in Johannesburg, South Africa on mid-week mornings. 825 secondary school students volunteered for this study. N/A. The students, (16+/-1 years), 61% female, reported significantly less time in bed (p<0.001) on a school night (453+/-70 minutes), compared to weekend nights (476+/-128 minutes). On the school night, they reported a mean sleep onset latency of 17 minutes, with 45% of the sample falling asleep in less than ten minutes. Short sleep onset latency and short in-bed wakefulness both were positively related to a high sleep efficiency and subjective sleep quality. On the previous day, 72% of the adolescents had consumed caffeinated beverages and 56% had exercised, but these behaviors did not significantly influence their nighttime sleep. The majority (77%) of students had napped the previous day and 8% had taken medication to fall asleep that night. 40% of the students felt that they could fall asleep mid-morning, if given the chance, but their sleepiness was independent of their nighttime sleep quality or duration. Similarly to teenagers around the world, South African adolescents get insufficient sleep during the week, which they attempt to compensate for on the weekends. A large proportion of the students are also sleepy during the school day, which may influence their academic performance.

A multifactorial approach employing melatonin to accelerate resynchronization of sleep–wake cycle after a 12 time‐zone westerly transmeridian flight in elite soccer athletes

Rapid transmeridian translocation through multiple time zones has a negative impact on athletic performance. The aim of the present study was to test the timely use of three factors (melatonin treatment, exposure to light, physical exercise) to hasten the resynchronization of a group of elite sports competitors and their coaches to a westerly transmeridian flight comprising of 12 time-zones. Twenty-two male subjects were included in the study. They were professional soccer players and their coaches who travelled to Tokyo to play the final game of the Intercontinental Coup. The day prior to departure, urine was collected from each subject from 18:00 to 06:00 hrs to measure the melatonin metabolite 6-sulphatoxymelatonin. Participants were asked to complete sleep log diaries from day 0 (preflight) to the day before returning to Buenos Aires (day 8). All subjects received 3 mg of melatonin p.o. daily at expected bedtime at Tokyo immediately after leaving Buenos Aires. Upon arrival at Tokyo the subjects performed a daily physical exercise routine outdoors at two restricted times of the day (from 08:00 to 11:00 hrs in the morning and from 13:00 to 16:00 hrs in the afternoon). Exposure to sunlight or physical exercise at other times of the day was avoided. Except for the number of awakenings (which increased on days 1 and 3) and sleep latency (which decreased on days 2, 6 and 8), there was an absence of significant changes in subjective sleep parameters as compared with preflight assessment. Sleep quality and morning alertness at Tokyo correlated significantly with preflight 6-sulphatoxymelatonin excretion. Mean resynchronization rate of sleep-wake cycle to the 12 hr-time shift was 2.13 +/- 0.88 days, significantly different from the minimal resynchronization rate of 6 days expected after a 12-time-zones flight. The results indicate that the combination of melatonin treatment, an appropriate environmental light schedule and timely applied physical exercise can be useful to help elite athletes to overcome the consequences of jet lag.

A Prospective Study of Sleep, Mood, and Cognitive Function in Postpartum and Nonpostpartum Women

Objective: To compare the sleep patterns, mood states, and cognitive functioning of primiparous mothers during the first 3 weeks postpartum with those of a control group of nonpostpartum women and to assess the relationships among these variables.Methods: For the first 3 weeks postpartum, 30 primiparous women and 28 nonpostpartum mothers completed daily assessments of mood and recorded multiple aspects of sleep including time of retiring, occurrence and duration of sleep interruption, time of awakening, and morning alertness. Objective measures of memory, attention/concentration, and psychomotor performance were obtained on three occasions.Results: Postpartum women reported more evening awakenings, more time awake after retiring, and more naps than controls, but overall sleep time was similar. New mothers experienced a higher level of dysphoric mood during the first week than nonpostpartum controls; however, controlling for the effect of “time awake” at night eliminated the significant effect for dysphoric mood. Few differences were observed on the multiple assessments of cognitive function; however, performances of new mothers on memory and psychomotor tasks were likely to be influenced by sleep loss.Conclusion: Women must make important adjustments in their sleep patterns during the postpartum period. In the study group, these adjustments were largely successful, particularly after the first week postpartum, in avoiding the negative consequences of sleep disturbances such as dysphoric mood and impaired cognitive function. Nevertheless, the significant associations between sleep indices and mood and objective measures of cognitive function point to the importance of encouraging appropriate amounts of sleep for recently delivered women.

Psychomotor and cognitive performance in nonapneic snorers: preliminary findings.

Snoring is a common phenomenon and a primary symptom in obstructive sleep apnea syndrome, a sleep-related breathing disorder in which neuropsychological function is reported to be impaired. The first purpose of the present study was to compare cognitive and motor function in 25 heavy nonapneic snorers and 26 sleep apneics. As the basis for impairments in heavy nonapneic snorers is still unclear, the influence of nighttime breathing disturbances and morning alertness, respectively, on daytime performance was evaluated too. Nonapneic snorers exhibit more slow wave sleep and tend to have fewer changes in sleep stage than sleep apnea patients, but values for other sleep variables are similar. Snorers also show comparable alertness. Deficits in immediate visual memory and in visuospatial reasoning are not found. However, there are some indications that snorers show decreased manual dexterity and eye-hand coordination for the nonpreferred hand and that they have deficits in focused attention. In addition, snorers may show difficulties in finger-tapping speed. These performance measures tend to be associated with reduced morning alertness, except for the score on focused attention which has a tendency to be related to the nocturnal breathing disturbances.

Neuropsychological functioning and determinants of morning alertness in patients with obstructive sleep apnea syndrome.

Neuropsychological functioning is reported to be impaired in patients suffering from obstructive sleep apnea syndrome (OSAS). This syndrome is characterized by nocturnal respiratory disturbances, blood oxygen desaturations, sleep fragmentation, and excessive daytime sleepiness. Opinions are divided concerning the exact relationship between the observed cognitive deficits, nocturnal hypoxia, sleep disruption, and impaired daytime alertness. In the present study, morning neuropsychological function of 26 moderate to severe middle-aged sleep apneics is compared to that of 22 primary insomniacs. There were no performance differences on a range of neuropsychological tests among the two patient groups. In addition, the data suggest that morning alertness impairment, which is closely associated with a lack of slow wave sleep (SWS) and rapid eye movement (REM) sleep, is of major importance in inducing poorer cognitive performance in patients with moderate to severe sleep apnea.

Delayed sleep phase syndrome: a review of its clinical aspects.

Delayed sleep phase syndrome is a common but little reported cause of severe insomnia. Since it was first described, few detailed reports of delayed sleep phase syndrome have appeared, and treatment methods have not been reviewed. From the literature, the authors provide diagnostic descriptions and review treatment methods, and from their sleep disorder clinic, they describe the management and outcome of the largest series of patients with delayed sleep phase syndrome thus far reported. The authors reviewed all articles with primary data on delayed sleep phase syndrome published through 1993 and add data from a group of 33 patients at their sleep disorder clinic. Delayed sleep phase syndrome involves undesirably late bedtimes and arising times, early night insomnia, and poor morning alertness but lack of insomnia on vacations. The mean bedtime and arising time for the 33 patients were 4:00 a.m. and 10:38 a.m., respectively. Twenty-five patients were, or had been, depressed. Individual responses to treatments varied widely. Seventeen patients showed little treatment response. Delayed sleep phase syndrome had a worse treatment outcome than other sleep disorders. Delayed sleep phase syndrome presents in a heterogeneous manner. In the sleep disorder clinic population, it was often associated with major depression and was more resistant to treatment than other sleep disorders. Multiple and varied treatments are required.

Sleep, morning alertness and quality of life in subjects treated with zopiclone and in good sleepers. Study comparing 167 patients and 381 good sleepers

From 20,000 households regularly surveyed by a national survey institute (Sofres), two groups were selected and questioned (using a 23-item questionnaire) about sleep vigilance and quality of life. The first group was composed of insomniacs using zopiclone for the last 12 months and no other CNS treatments (167 subjects). The second group was composed of 381 "good sleepers" selected as having no or occasionally one sleep disturbance in the last 12 months. No difference was found between the two groups in average total sleep time. Sleep disturbances were statistically equal in the two groups except for difficulties in initiating sleep which is more present for zopiclone users (13% vs 3%). Vigilance was mostly comparable in both groups.Five aspects of quality of life explored by the questionnaires (the professional, relational and sentimental, domestic, leisure and safety aspects) appeared to be comparable in the two groups.

Chronic Treatment with Fluvoxamine, Clovoxamine, and Placebo: Interaction with Digoxin and Effects on Sleep and Alertness

The influence of 17 days of administration of fluvoxamine or clovoxamine, two new antidepressant agents, on the kinetics of a single intravenous dose of digoxin, and on self-rated parameters of sedation, mood, and sleep, was evaluated in a series of healthy volunteers. In the fluvoxamine study, subjects received fluvoxamine, 100 mg daily, or matching placebo for 17 consecutive days in a crossover design. For the clovoxamine study, subjects received clovoxamine, 150 mg daily, or placebo for 17 days. All treatments were double blind. At the end of each treatment, digoxin kinetics were evaluated following a single 1.25 mg intravenous dose. Compared to the placebo condition, fluvoxamine had no significant influence on digoxin elimination half-life (57 vs 47 hours), volume of distribution (10.5 vs 10.3 liters/kg), total clearance (2.4 vs 3.0 ml/min/kg), or 72 hour urinary excretion (33 vs 37 percent of the dose). Likewise clovoxamine did not alter digoxin elimination half-life (39 vs 40 hours), volume of distribution (10.7 vs 10.2 liters/kg), or total clearance 3.4 vs 3.4 ml/min/kg). 72 hour urinary excretion of digoxin was slightly increased by clovoxamine (41 vs 50 percent of the dose, P less than .05). Self-ratings indicated a sedating effect of fluvoxamine, with reports of difficulty attaining morning alertness. These effects were not reported with clovoxamine. Thus clovoxamine and fluvoxamine appear to have differential effects on sleep and alertness in healthy volunteers. However, neither have an important influence on the kinetics of digoxin.

Hypnotic Activity of Diphenhydramine, Methapyrilene, and Placebo

In a double-blind controlled study, an oral dose of diphenhydramine hydrochloride (12.5, 25, or 50 mg), methapyrilene fumarate (36, 72, or 144 mg), or placebo was administered to 1295 post-partum patients if they complained of, or anticipated, a sleep problem. Hypnotic activity was assessed clinically by subjective and objective techniques. Methapyrilene and diphenhydramine, at all doses, were found to be effective hypnotics in comparison to placebo, based on sleep latency, sleep duration, awakening in the night, global evaluation, and morning alertness. Increasing the dose of these drugs, in the range studied, produced a minimal increase in effectiveness.

The diurnal rhythm of adrenaline secretion in subjects with different working habits.

AbstractPátkai, P. The diurnal rhythm of adrenaline secretion in subjects with different working habits. Acta physiol. scand. 1971. 81. 30–34.Subjects classified as habitual morning vs. evening workers on the basis of their answers to a questionnaire, were compared with regard to catecholamine excretion under conditions of relaxation in the morning and in the evening. It was shown that individuals who preferred to work in the evening, excreted more adrenaline in the evening than in the morning, while individuals characterized by morning alertness excreted more adrenaline in the morning than in the evening, also when relaxing. With regard to noradrenaline excretion there was no marked difference between the groups.