This review aims to introduce the basic neurobiological aspects of dream. There have been long debates on whether the neurobiology of rapid eye movement (REM) sleep is identical to that of dream. However, many theories on dream are based on the findings of REM sleep. Bizarre cognition and intense emotion in dream have been suggested to derive from physiological (e.g. desynchronized gamma oscillation and postsynaptic inhibition), chemical (e.g. decreased noradrenalin and serotonin, increased acetylcholine and modulation of dopamine), anatomical (e.g. deactivation of dorsolateral prefrontal cortex and activation of limbic and paralimbic areas) change in REM sleep. In addition, dream has been suggested to play its neurobiological roles. Processing of negative emotion may be one of the functions of dream. Dream is also supposed to consolidate memory, especially semantic memory. Despite a number of hypotheses and debates, the neurobiological mechanism of dream generation has not been concluded.
Acetylcholine ; Cognition ; Dreams ; Memory ; Neurobiology ; Prefrontal Cortex ; Semantics ; Serotonin ; Sleep, REM

OBJECTIVES: The purpose of this study was to assess the clinical and polysomnographic characteristics of Korean patients with obstructive sleep apnea syndrome (OSAS), especially in relation to differences due to age and gender. METHODS: All subjects were consecutive patients who were proven to have OSAS with nocturnal polysomnography. They were interviewed with a structured interview format including sociodemographic information, past medical history, medication, and sleep-related history. Simultaneously, they were also given Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) to answer in order to check subjective sleep quality and subjective sleepiness. RESULTS: Mean age of the 308 subjects was 49.5+/-13.3 years, with 77.6% of the subjects being males and 22.4% of the subjects being females. The aging effects on the sleep architecture in Korean OSAS corresponded with normal aging, but with the effect of OSAS itself superimposed, the extent of aging effects was more marked than that of normal aging. The severity of Korean patients of OSAS was not correlated with age. When divided into age subgroups, significant correlation was found between RDI and BMI in patients of each subgroup of those in the 4th to 7th decades. The oldest subgroup (>70 years) described their subjective sleep quality as poorer than any other age subgroups, despite of less subjective drowsiness. The severity of OSAS and the change of sleep architecture of male subjects turned out to be severer than those of female ones. The female/male ratio of the subjects tended to increase with aging. CONCLUSIONS: The aging effect on the sleep architecture in Korean OSAS seems to be a mixture of the changes by normal aging and sleep disorder per se. The severity of OSAS was not correlated with age, but highly correlated with BMI. The severity of OSAS and the change of sleep architecture of male patients were severer than those of female ones.
Aging ; Body Mass Index ; Female ; Humans ; Male ; Polysomnography ; Sleep Apnea, Obstructive ; Sleep Stages

PURPOSE: This study aimed to investigate the differences of traumatic experience according to menstrual regularity among North Korean woman refugees in South Korea. METHODS: This study used a sample of convenience consisting of 131 women in 5 government resettlement centers throughout South Korea. The traumatic experiences scale for North Korean defectors was used for identifying traumatic experience. Data were collected between June 2012 and December 2012. Data was analyzed using mean, percentage, and t-test. RESULTS: The rate of irregular menstruation was 35.1%. Irregular menstruation group had more traumatic experiences than regular one (t=-1.78, p=.038). CONCLUSION: This study demonstrates that their reproductive health promotion was necessary regarding menstrual problem. Also, their severe traumatic experiences were considered into healthcare program.
Delivery of Health Care ; Democratic People's Republic of Korea ; Female ; Humans ; Korea* ; Menstruation ; Refugees* ; Reproductive Health

OBJECTIVES: The present study aims to investigate the effects of physical illness on depression in North Korean Defectors. METHODS: One hundred forty-four North Korean Defectors(20 males, 124 females) and 376 South Koreans 133 males, 243 females) in Incheon Metropolitan areas participated the present study. Face-to-face interview was conducted for demographic information including presence of physical illnesses. To investigate depressive symptoms, all participants were required to complete the Center for Epidemiologic Studies-Depression scale (CES-D). RESULTS: After controlling gender, age, marital status, educational year, employment status and physical illness, North Korean Defectors showed higher CES-D score than South Koreans(beta=0.449, p<0.001). Within North Korean Defectors, the presence of physical illnesses independently was related to higher CES-D score(beta=0.243, p<0.001). However, within South Koreans, the presence of physical illnesses did not significantly predict CES-D score. North Korean Defectors with physical illness have higher CES-D score than North Korean Defectors without physical illness(26.8+/-13.8 versus 19.7+/-12.7). However, there was no significant differences of CES-D score between South Koreans with physical illness and South Koreans without physical illness(10.3+/-9.8 versus 9.3+/-8.8). CONCLUSION: Compared to South Koreans, North Korean Defector showed higher depressive symptoms independently from gender, age, education, employment, marriage. In addition, only North Korean Defectors showed the relationship between depression and physical illness. Our study suggests that depression should be assessed when North Korean Defectors have physical illness.
Depression ; Employment ; Humans ; Male ; Marital Status ; Marriage

OBJECTIVE: The purpose of this paper is to study the possible differences in clinical and polysomnographic findings, depending on the presence or absence of subjective complaints of abnormal sleep behavior, in patients with RWA on polysomnography. METHOD: We reviewed patient records and polysomnographic data of patients referred to the Sleep Laboratory at Seoul National University Hospital from June 1996 through October 2002. We defined the manifest RBD group (n=32) as patients having both complaints of abnormal sleep behavior and RWA on polysomnography. The latent RBD group (n=20) consisted of patients who exhibited RWA on polysomnography but did not complain of abnormal sleep behavior. The clinical characteristics and polysomnographic findings between the two groups were compared and analyzed. RESULTS: Fifty-two subjects had RWA, as detected by polysomnography (42 males and 10 females, mean age of 55.1+/-19.1 years). Subjects in the manifest RBD group were significantly older than those in the latent RBD group (61.59+/-13.5 vs. 44.70+/-2.76 years, independent t-test, p<0.01). More subjects in the manifest RBD group exhibited abnormal REM behavior on polysomnography than did subjects in the latent RBD group (81.3 vs. 50.0%, Fisher's exact test, p<0.05). No significant differences between the groups were found in the prevalence of brain disorders and primary sleep disorders, gender proportion, and sleep architecture. CONCLUSION: No difference in sleep architecture was found between the manifest and the latent RBD groups. Only age and the presence of abnormal sleep behavior on polysomnography differentiated the two groups. We suggest that RWA on polysomnography without complaints of abnormal sleep behavior may be early manifestation of manifest RBD. Attention to RWA on polysomnography is necessary to help prevent full-blown RBD from developing.
Brain Diseases ; Female ; Humans ; Male ; Mental Disorders* ; Polysomnography ; Prevalence ; REM Sleep Behavior Disorder ; Seoul ; Sleep Wake Disorders ; Sleep, REM*

OBJECTIVE: The purpose of this study is to investigate the prevalence rate of OSA in subjects whose main sleep complaint is insomnia and to find differential factors of OSA in these insomniac subjects. METHOD: We reviewed the medical records and polysomnographic findings of patients referred to the Sleep Laboratory at Seoul National University Hospital from January 1996 to December 2002. Four-hundred and seventy subjects complained of insomnia as their main sleep problem (235 males and 235 females, mean age 53.6+/-12.4 years). First, we investigated the prevalence rate of OSA in these insomniac patients. Second, we compared the clinical and demographic characteristics of the OSA-associated group with those of the non-associated group. Third, we examined whether the degree or presence of differential factors within the OSA group correlate with severity of OSA, as determined by the respiratory disturbance index (RDI). RESULTS: Among 470 insomniac subjects, 125 subjects (26.6%) were diagnosed as OSA by nocturnal polysomnography. OSA-associated subjects were significantly older (58.4+/-12.3 years vs. 51.8+/-11.2 years, p<0.01), and had significantly higher body mass index (BMI) (23.4+/-3.3 kg/m2 vs. 22.5+/-3.1 kg/m2, p=0.44) than non-associated subjects. The OSA-associated group had more subjects with male gender (64.0 % vs. 44.9 %, p<0.01), hypertension (20.0 % vs. 9.3 %, p<0.01) or snoring (96.0 % vs. 63.5 %, p<0.01). Within the OSA-associated group, age had a significant positive correlation with RDI (p=0.01). CONCLUSION: We found that a considerable portion of patients complaining of insomnia as their main sleep problem were diagnosed as OSA. Snoring, old age, male gender, obesity, and comorbid hypertension were found to be differential factors of OSA in insomniac patients. We suggest that diagnostic efforts including nocturnal polysomnography are needed for insomniac patients with any of the above risk factors of OSA.
Body Mass Index ; Female ; Humans ; Hypertension ; Male ; Medical Records ; Obesity ; Polysomnography ; Prevalence ; Risk Factors ; Seoul ; Sleep Apnea, Obstructive* ; Sleep Initiation and Maintenance Disorders* ; Snoring

INTRODUCTION: The objective of the present study was to investigate the defense style of insomnia patients and to grasp the differences in defense style between primary insomnia patients and insomnia patients with history of major depressive disorder. METHODS: Forty three subjects with insomnia (11 subjects with primary insomnia and 32 subjects with major depressive disorder) and 138 control subjects participated in this study. To diagnose insomnia and major depressive disorder, interviews including structured clinical interview for DSM-IV (SCID-IV) were done. To assess the defense style, self-reported Korean version of Defense Style Questionnaire (K-DSQ) were completed by the participants. RESULTS: Compared to normal controls, subjects with insomnia used more acting out (t=3.25, p<0.01), consumption (t=2.66, p<0.01), fantasy (t=3.51, p<0.001), resignation (t=5.42, p<0.001), suppression (t=3.28, p<0.01), projection (t=3.92, p< 0.01), splitting (t=4.31, p<0.01), undoing (t=2.66, p<0.01), withdrawal (t=6.72, p<0.001) and isolation (t=3.80, p<0.001), and less omnipotence (t=4.08, p<0.001) and humor (t=3.20, p<0.01). Compared to normal controls, subjects with primary insomnia used more undoing and withdrawal. Compared to subjects with primary insomnia, subjects with insomnia with history of major depressive disorder used more resignation and withdrawal, and less humor. CONCLUSION: In the current study, there were differences in defenses between primary insomnia patients and insomnia patients with major depressive disorder history. To evaluate the pattern of defenses through the K-DSQ might provide important clues to differentiate these two conditions.
Acting Out ; Depressive Disorder, Major ; Diagnostic and Statistical Manual of Mental Disorders ; Fantasy ; Hand Strength ; Humans ; Surveys and Questionnaires ; Sleep Initiation and Maintenance Disorders

As insomnia is a common symptom caused by diverse disorders, treatment tools for the insomnia differ depending on the underlying cause. Hypnotics can be used for primary insomnia. As hypnotics show excellent short-term efficacy, they would be useful as short-term ( < 4 weeks) treatments for transient insomnia. There has been much controversy over long-term hypnotic use for chronic insomnia. Evidence supporting safety and efficacy of the long-term hypnotic use is insufficient. Therefore, rather than using hypnotics alone, non-pharmacological treatments are recommended more for chronic primary insomnia. Although various benzodiazepines have widely been used as hypnotics, there have been concerns over tolerance, rebound insomnia, dependency, cognitive decline and psychomotor slowness. In efforts to relieve these concerns, selective benzodiazepine agonists like zolpidem have been introduced as novel hypnotics. Sedating antidepressants, melatonin and anti-histamine have also been used in order to manage insomnia. However, their efficacy for primary insomnia has yet to be proven.
Antidepressive Agents ; Benzodiazepines ; Dependency (Psychology) ; Hypnotics and Sedatives ; Melatonin ; Pyridines ; Sleep Initiation and Maintenance Disorders

OBJECTIVES: Psychiatry in North Korea is believed to seem very different from psychiatry in South Korea. However, there is nearly no information regarding psychiatry in North Korea until now. Our study aimed to get information about North Korean psychiatry. METHODS: Three North Korean defectors in South Korea, whose clinical experience as medical doctors in North Korea was over 10 years, were recruited. They underwent the semi-structured interview, content of which included the clinical experience with psychiatric patients, the details of psychiatry, the treatment of psychiatric patients, the stigma of mental illness, and the suicide, in North Korea. RESULTS: In North Korea, psychiatric department was called as 49th(pronounced as Sahsip-gu-ho in Korean). Only patients with vivid psychotic symptoms came to psychiatric department. Non-psychotic depression or anxiety disorders usually were not dealt in psychiatry. The etiology of mental illness seemed to be confined to biological factors including genetic predisposition. Psychosocial or psychodynamic factors as etiology of mental illness appeared to be ignored. Psychiatry was apparently separated from political or ideological issues. The mainstay of psychiatric treatment is the inpatient admission and out-of-date therapy such as insulin coma therapy. Stigma over mental illness was common in North Korea. Suicide is considered as a betrayal to his/her nation, and has been reported to be very rare. CONCLUSION: The situation of psychiatry in North Korea is largely different from that of South Korea. Although some aspects of North Korean psychiatry are similar to psychiatry in former socialist countries, North Korean psychiatry is considered to have also its unique characteristics.
Anxiety Disorders ; Biological Factors ; Convulsive Therapy ; Democratic People's Republic of Korea ; Depression ; Genetic Predisposition to Disease ; Humans ; Inpatients ; Porphyrins ; Republic of Korea ; Suicide

INTRODUCTION: The objective of the present study was to investigate the independent effects of major depressive disorder (MDD) and insomnia on somatization, respectively. METHODS: A total of 181 participants (73 males and 108 females ; mean age 41.59+/-8.92) without serious medical problem were recruited from a community and a psychiatric clinic in Republic of Korea. Subjects were divided into 4 groups based on the Structured Clinical Interview for DSM-IV axis I disorder (SCID-IV) and sleep questionnaire : 1) normal controls (n=127), 2) primary insomnia (n=11), 3) MDD without insomnia (n=14), and 4) MDD with insomnia (n=29). All participants were requested to complete the somatization subscores of the Symptom Checklist-90-Revised (SCL-90-R). RESULTS: There were significant between-group differences in somatization score (F=25.30, p<0.001). Subjects with both MDD and insomnia showed higher somatization score compared to normal control (p<0.001), subjects with primary insomnia (p=0.01), or MDD subjects without insomnia (p<0.001). Subjects with primary insomnia had higher somatization score than normal controls (p<0.01), while there was no significant difference between MDD subjects without insomnia and normal controls. In multiple regression, presence of insomnia predicted higher somatization score (beta=0.44, p<0.001), while there was only non-significant association between MDD and somatization (beta=0.14, p=0.08). CONCLUSION: In the current study, insomnia was associated with somatization independently from major depression. Subjects with primary insomnia showed higher somatization. Within MDD patients, presence of insomnia was related to higher somatization. Our finding suggests that insomnia may partly mediate the relationship between depression and somatization.
Axis, Cervical Vertebra ; Depression ; Depressive Disorder, Major ; Diagnostic and Statistical Manual of Mental Disorders ; Female ; Humans ; Male ; Surveys and Questionnaires ; Republic of Korea ; Sleep Initiation and Maintenance Disorders