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Sleep: Understanding the Basics

Basics of Sleep Introduction

Sleep is defined as a state of unconsciousness from which a person can be aroused. In this state, the brain is relatively more responsive to internal stimuli than external stimuli. Sleep should be distinguished from coma. Coma is an unconscious state from which a person cannot be aroused. Sleep is essential for the normal, healthy functioning of the human body. It is a complicated physiological phenomenon that scientists do not fully understand.

Historically, sleep was thought to be a passive state. However, sleep is now known to be a dynamic process, and our brains are active during sleep. Sleep affects our physical and mental health, and is essential for the normal functioning of all the systems of our body, including the immune system. The effect of sleep on the immune system affects one’s ability to fight disease and endure sickness.

States of brain activity during sleep and wakefulness result from different activating and inhibiting forces that are generated within the brain. Neurotransmitters (chemicals involved in nerve signaling) control whether one is asleep or awake by acting on nerve cells (neurons) in different parts of the brain. Neurons located in the brainstem actively cause sleep by inhibiting other parts of the brain that keep a person awake.  



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Sleep

Sleep Disorders in Women Overview

Women are twice as likely as men to have difficulties falling asleep or staying asleep. Younger women have sounder sleep with fewer disturbances. Some women, however, are prone to sleep problems throughout their reproductive years. Only recently has the medical community focused on women's sleep disorders.  

A number of factors may affect women’s sleep. Changes in hormonal levels, stress, illness, lifestyle, and sleep environment may impact sleep. Pregnancy- and menstrual-related hormonal fluctuations may affect sleep patterns, mood, and reaction to stress. Many women have premenstrual sleep disturbances. Difficulty falling asleep, nighttime waking, difficulty waking up, and daytime sleepiness all are linked to premenstrual changes. Insomnia (sleeplessness) is one of the most common symptoms of premenstrual syndrome (PMS).

Psychosocial stress may threaten sleep more than ...

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Sleep Disorder: Problems Associated with Other Disorders »

Sleep disturbances in youth represent highly common phenomena that, in severe forms, can interfere with daily patient and family functioning.

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