• Sleep Medicine and Psychophysiology
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• v.2 no.2
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• pp.105-114
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• 1995

Schiophrenia is characterized by a variety of cognitive dysfunctions. A number of research findings suggest that schizophrenic patients have global deficits in cognitive functions, such as attention, memory, executive functions, and motor functions. These cognitive deficits, once they arise, tend to become relatively stable. In spite of much efforts to search for the cognitive dysfunctions in schizophrenia, there are no specific deficits or localizations found. It is necessary that future neuropsychological research of schizophrenia should include relationships between symptoms and cognitive dysfunctions and their relationships to treatment.

• Sleep Medicine and Psychophysiology
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• v.4 no.1
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• pp.39-48
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• 1997

Memory disorder is the most consistent neuropsychological finding in schizophrenia and seems to be a stable trait in it. It is suggested that memory dysfunction found in patients with schizophrenia is primary to biological abnormalities, not secondary to attention deficits they have. Although temporal lobe structures including hippocampus and thalamus have traditionally been thought to be implicated regions for memory disorder in schizophrenia, recent studies indicate the possibility of abnormalities in the frontal lobe and the neural circuits between brain regions. Advanced research methods such as functional imaging technique are expected to produce more detailed informations about memory function in schizophrenia.

• Sleep Medicine and Psychophysiology
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• v.15 no.1
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• pp.12-16
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• 2008

Light therapy (also called light treatment or phototherapy) involves scheduled exposure to bright artificial light. Evidence-based treatments for sleep disorders especially for circadian rhythm sleep disorders include light therapy and pharmacotherapy. In clinical practice, many of patients with sleep problems tend to impair circadian rhythmicity. Considering that light is the most potent entraining agent of circadian rhythm, careful use of light therapy can be recommended for patients with several kinds of sleep disorders. I briefly review the possible therapeutic mechanisms and clinical applications of light therapy, focusing on circadian sleep disorders.

• Sleep Medicine and Psychophysiology
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• v.9 no.2
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• pp.86-95
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• 2002

Various sleep-related problems are common in pregnant women. Sleep disorders may result in intrauterine growth restriction as well as harm to pregnant women. Pharmacotherapy of sleep disorders in pregnancy require cautious judgement. All physicians managing sleep-related problems of pregnant women in clinical practice need to understand sleep-related problems and their management in pregnancy. Therefore, I have reviewed the literature on normal sleep, sleep disorders and their management in pregnancy.

• Sleep Medicine and Psychophysiology
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• v.20 no.1
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• pp.10-14
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• 2013

Sleep disturbances are commonly encountered problems in cancer patients. Sleep has a role in maintenance of immunity, metabolism, and quality of life but little has been known about the prevalence, risk factors, and effects on prognosis of sleep disturbances in patients with cancer. Also little attention has been made on proper assessment and management of sleep disorders in these patients. Recently, there have been some reports that sleep disorders are related with development of many cancers such as breast, colorectal, prostate, and endometrial cancers. An intermittent hypoxia and a disruption of circadian rhythm are considered as one of the possible mechanisms of cancer developments. More aggressive evaluation and meticulous management of sleep disturbances in cancer patients are essential to improve quality of life as well as prognosis.

• Sleep Medicine and Psychophysiology
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• v.26 no.2
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• pp.75-85
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• 2019

A lucid dream is defined as a dream during which a dreamer is aware that she/he is dreaming. The existence of lucid dream has long been known in the literature, but it hasn't been long before it has received attention in sleep medicine. Although many studies have been conducted since validation of the lucid dream in polysomnography by Steven LaBerge in the 1980s, the neuroscience of lucid dreams is still not fully understood. Here the neuroscientific literature on lucid dreaming, including electroencephalographic, neuroimaging, pharmacological and brain stimulation studies, are reviewed. Also this review gives an overview on how lucid dreams are used in clinical and nonclinical areas, ranging from nightmare therapy to research on consciousness and creative problem solving.

• Sleep Medicine and Psychophysiology
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• v.16 no.1
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• pp.10-15
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• 2009

Sleep problems and disorders are common in patients with cancer. Sleep of the cancer patients is affected by various factors, including thermoregulatory changes associated with chemotherapy and radiotherapy, cancer related symptoms, such as pain, fatigue, and emotional difficulties. As one of the most common symptoms in cancer patients, fatigue is positively correlated with sleep difficulties. Cytokine is also frequently associated with chemotherapy and radiotherapy. It provokes excessive daytime sleepiness and hypersomnia. Medications for controlling pain, depression, and anxiety can affect sleep of the cancer patients. Medications as well as behavior therapy are reported to be effective for controlling sleep problems, and the physicians need to be accustomed to use the modalities appropriately. This paper reviews causative factors, evaluation, and management of sleep problems and disorders, experienced by cancer patients.

• Sleep Medicine and Psychophysiology
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• v.16 no.1
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• pp.22-27
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• 2009

Regulation of respiration differs significantly between wakefulness and sleep. Respiration during wakefulness is influenced by not only automatic control but also voluntary and behavioral control. Sleep is associated with definite changes in respiratory function. With the onset of sleep, voluntary control of ventilation that overrides automatic control during wakefulness becomes terminated. Also ventilatory response to various stimuli including hypoxemia and hypercapnia is decreased. With these reasons respiration during sleep becomes fragile and unstable so that marked hypoxemia can be happened in patients with lung disease especially during REM sleep. Obstructive sleep apnea may also be developed if upper airway resistance is increased in addition to these blunted ventilatory responses.

• Sleep Medicine and Psychophysiology
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• v.16 no.1
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• pp.16-21
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• 2009

In accordance with the development of EEG and polysomnography in the field of sleep research, the sleep onset period (SOP) between wakefulness and sleep has been considered an important part for understanding the physiology of sleep. SOP in the transition from wakefulness to sleep is a gradual process integrating various viewpoints such as behavior, EEG, physiology and subjective report. Particularly, based on understanding of EEG changes during sleep, SOP has been regarded as a pattern of topographical change in specific frequency and specific state in EEG. Studies on quantitative EEG (qEEG) and event-related potential (ERP) have suggested that SOP shows the changes of functional coordination at the specific cortical areas in qEEG and the changes of regular patterns in response to environmental stimulation in ERP. The development of sleep EEG and topographic mapping of EEG is expected to integrate various viewpoints of SOP and clarify the neurophysiologic mechanism of SOP further.

• Sleep Medicine and Psychophysiology
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• v.7 no.2
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• pp.79-83
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• 2000

Sleep disturbances are frequently associated with neurological disorders. Sleep disorders interfere with rehabilitation of patients with neurological disorders such as stroke and may increase the severity of their symptoms and recurrence rate of stroke. The treatment of sleep apnea syndrome is particularly important in managing patients with cerebral infarction of whom 50-80% have moderate to severe sleep apnea. Sleep apnea produces not only poor quality sleep but also excessive daytime sleepiness, fatigue and lack of energy. Sleep problems frequently found in patients with dementia are sleep-wake cycle abnormality, fragmentation of sleep, nocturnal insomnia, decreased slow wave sleep and REM sleep, and sleep disordered breathing. The management of sleep disturbances is very important for controlling symptoms such as nocturnal wandering and sundowning syndrome in patients with dementia. Parkinson's disease and epilepsy are other neurological disorders that may have sleep disturbances.