No abstract available.
Sleep Initiation and Maintenance Disorders*

No abstract available.

Excessive daytime sleepiness in childhood might be abnormal phenomenon and often related to the sleep disorders or insufficient sleep duration. The most common cause of excessive daytime sleepiness would be insufficient sleep. However, narcolepsy, idiopathic hypersomnia, circadian rhythm sleep disorders, medication, medical illness and other sleep disorders that could cause insomnia and poor quality of sleep also result in excessive daytime sleepiness. The misdiagnosed and untreated excessive daytime sleepiness in childhood can lead to serious developmental and educational problem.
Child ; Humans ; Hypersomnolence, Idiopathic ; Narcolepsy ; Sleep Wake Disorders ; Sleep Wake Disorders, Circadian Rhythm ; Sleep Initiation and Maintenance Disorders

Circadian rhythm is a global phenomenon, the control mechanisms of which are manifested at every level of biological organization, from genes and intracellular mechanisms to networks of cell populations, and to all central neuronal systems at the organismic level. In pharmacotherapy, the pharmacokinetic parameters such as drug absorption and distribution, drug metabolism, and renal elimination show diurnal variations. The symptoms and signs in diseases like asthma, myocardiac infarction, angina pectoris, hypertension and stroke also show diurnal fluctuations. These observations require drug treatment considering the circadian rhythm of body function and disease. Circadian time has to be taken into account as an important variable influencing a drug's pharmacokinetics and/or its effects or side effects in clinical practice.
Absorption ; Angina Pectoris ; Asthma ; Circadian Rhythm ; Clinical Medicine* ; Drug Therapy ; Hypertension ; Infarction ; Metabolism ; Neurons ; Pharmacokinetics ; Stroke

Sleep changes substantially with age. There is a phase advance in the circadian sleep cycle and increased waking after sleep onset. The elderly people wake more frequently during the night and experience fragmented sleep and excessive daytime sleepiness. The prevalence of sleep disorders increases with age, and the composition of sleep disorders in the elderly differs from that in the young. The most frequently encountered sleep disorders are psychophysiologic insomnia, sleep disturbance due to dementia, sleep-related respiratory disorder, restless legs syndrome and periodic limb movement disorder, and REM sleep behavior disorder. To treat the elderly sleep problem appropriately, it is important to know how sleep pattern changes as we age and to understand the cause of sleep-related symptoms. This article will review the sleep physiology and common sleep disorders in the elderly.
Aged* ; Dementia ; Humans ; Nocturnal Myoclonus Syndrome ; Physiology* ; Prevalence ; REM Sleep Behavior Disorder ; Restless Legs Syndrome ; Sleep Wake Disorders* ; Sleep Initiation and Maintenance Disorders

A 'circadian rhythm' is a self-sustained biological rhythm (cycle) that repeats itself approximately every 24 hours. Circadian rhythms are generated by an internal clock, or pacemaker, and persist even in the absence of environmental time cues, collectively termed 'zeitgebers.' Although organisms generate circadian rhythms internally, they are entrained by environmental stimuli, particularly the light-dark cycle. Measurement of the endogenous melatonin rhythm provides relatively reliable surrogate way of assessing the timing of the internal circadian clock. Also, core body temperature and cortisol can be used as markers of circadian rhythms. The sleep-wake cycle, body temperature, and melatonin rhythm have a stable internal phase relationship in humans and other diurnal species. They play an important role in controlling daily behavioral rhythms including task performance, blood pressure, and synthesis and secretion of several hormones. In this review, we address not only the properties, methods of measurement, and markers of circadian rhythms, but also the physiological and psychological importance of human circadian rhythms.
Blood Pressure ; Body Temperature ; Circadian Clocks ; Circadian Rhythm* ; Cues ; Humans ; Hydrocortisone ; Melatonin ; Photoperiod ; Task Performance and Analysis

Circadian rhythms have been observed to be disturbed in mood disorders, especially seasonal affective disorder (SAD). Clock related gene variants also have been suggested to be associated with seasonality (seasonal variations in mood and behavior). This study tested the potential association between a length polymorphism of Period3 gene and seasonal variations in mood and behavior. 297 Korean college students were genotyped for the Period3 polymorphism and were for evaluated the seasonal variation by Seasonal Pattern Assessment Questionnaire (SPAQ). The genotype frequencies were 0.76 for 4R/4R, 0.22 for 4R/5R and 0.013 for 5R/5R. The global seasonality score was not different among Period3 gene variants (4R/4R, 4R/5R and 5R/5R) except for 'sleep length' subscore. The 5R/5R genotype showed the higher 'sleep length' subscore than others (p=0.024). The comparison between seasonals (syndromal plus subsyndromal SAD determined by SPAQ) and non-seasonals did not show any significant difference in frequencies of genotypes. These findings suggest that there is a possibility that the investigated Period3 polymorphism may play a partial role in the susceptibility of seasonal variations in a Korean population.
Circadian Rhythm ; Genotype ; Humans ; Mood Disorders ; Surveys and Questionnaires ; Seasonal Affective Disorder ; Seasons*

No abstract available.
Sleep Apnea Syndromes*

As jet lag of modern travel continues to spread, there has been an exponential growth in popular explanations of jet lag and recommendations for curing it. Some of this attention are misdirected, and many of those suggested solutions are misinformed. The author reviewed the basic science of jet lag and its practical outcome. The jet lag symptoms stemed from several factors, including high-altitude flying, lag effect, and sleep loss before departure and on the aircraft, especially during night flight. Jet lag has three major components; including external desynchronization, internal desynchronization, and sleep loss. Although external desynchronization is the major culprit, it is not at all uncommon for travelers to experience difficulty falling asleep of remaining asleep because of gastrointestinal distress, uncooperative bladders, or nagging headaches, Such unwanted intrusions most likely to reflect the general influence of internal desynchronization. From the free-running subjects, the data has revealed that sleep tendency, sleepiness, the spontaneous duration of sleep, and REM sleep propensity, each varied markedly with the endogenous circadian phase of the temperature cycle, despite the facts that the average period of the sleep-wake cycle is different from that of the temperature cycle under these conditions. However, whereas the first ocurrence of slow wave sleep is usually associated with a fall in temperature, the amount of SWS is determined primarily by the length of prior wakefulness and not by circadian phase. Another factor to be considered for flight in either direction is the amount of prior sleep loss or time awake. An increase in sleep loss or time awake would be expected to reduce initial sleep latency and enhance the amount of SWS. By combining what we now know about the circadian characteristics of sleep and homeostatic process, many of the diverse findings about sleep after transmeridian flight can be explained. The severity of jet lag is directly related to two major variables that determine the reaction of the circadian system to any transmeridian flight, eg., the direction of flight, and the number of time zones crossed. Remaining factor is individual differences in resynchrnization. After a long flight, the circadian timing system and homeostatic process can combine with each other to produce a considerable reduction in well-being. The author suggested that by being exposed to local zeit-gebers and by being awake sufficient to get sleep until the night, sleep improves rapidly with resynchronization following time zone change.
Aircraft ; Circadian Clocks ; Circadian Rhythm* ; Diptera ; Fibrinogen ; Headache ; Individuality ; Sleep, REM ; Urinary Bladder ; Wakefulness

OBJECTIVES: In the past, latent dreams were emphasized in the psychiatric field, but these days the interest in manifest dreams is increasing as ego psychology develops. Hall and Nordby proposed that there are similarities between manifest dreams and real life. The Hall/Van de Castle System is a method of dream content analysis, which considers both the quantitive and qualitive analytic aspects of manifest dreams. METHODS: The dreams of 232 males and females (M: F=127: 105; mean age=21.02.7) were collected through the Most Recent Dream Method. Collected data were analyzed using the Hall/Van de Castle System. RESULTS: Female subjects tended to be more detailed and meticulous in reporting their dreams. The dreams of male subjects showed a higher percentage in self-negativity (2=6.64, df=1, p=0.004), and the dreams of female subjects showed a higher percentage in group character (2=6.64, df=1, p=0.0099), dreamer-involved success (2=3.12, df=1, p=0.048), and good fortune (2=4.52, df=1, p=0.034). CONCLUSION: This study suggests the norm of dream content of Korean college students, and it presents the differences between Korean males and females, and between Korean college students and American college students. This study may contribute to further studies on dream content analysis.
Dreams* ; Ego ; Female ; Humans ; Male ; Psychology