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Sleep is a state of altered consciousness, characterized by certain patterns of the brains activity and inactivity. An altered state of consciousness is when a person is not completely aware of their surroundings. Some researchers believe that we sleep to clear our minds of useless information. Other people believe that it is a type of primitive hibernation: we sleep to conserve energy.

Introduction: I’m sure everyone likes sleep. Everyone needs sleep to keep the least bit active through out there day. Sleep is an important factor for your body to restore energy. Sleeping is a time to rest your body from all the hard work you have done. It is relaxing so deeply that you lose consciousness of your surroundings.

14. Evolutionary theories often emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a 24-hour cycle of sleeping and waking—even if they are not exposed to the usual pattern of sunlight. To test this notion, eight paid volunteers were placed (individually) in a room in which there was no light from the outside and no clocks or other indications of time. They could turn the lights on and off as they wished. After a month in the room, each individual tended to develop a steady cycle. Their cycles at the end of the study were as follows: 25, 27, 25, 23,24, 25, 26, and 25.

In contrast, Phillips states animal sleep is different because the trouble of human sleep “is presumably not the experience of a woodchuck, or of any other animal that leads a life of pure instinct without the ability to reason, at least in the human terms in which we think of reasoning” (Phillips 135).

Circadian rhythms occur every 24 hours; an example of a circadian rhythm is the sleep-waking cycle. We are diurnal animals who are active during the daytime and asleep at night, other animals are nocturnal they are active at night but asleep during the day. The circadian rhythm depends on the interaction of physiological and psychological processes to be tuned into the sleep-waking cycle so energy is provided when needed. As diurnal humans we have a fairly stable sleep pattern with the time we go to sleep and the time we wake up, this consistency suggests an internal mechanism controls sleep, endogenous pacemaker. However, this can be overridden by external factors, exogenous zeitgebers.

The average human spends about 25 years of their life sleeping. That is equal to one-third of a person’s life. So if sleep is vital and common among every single human, what do you know about it? What happens when we sleep (Attention Grabber)? Before the 1950s, scientists believed that the brain would just “shut off” when we would go to sleep. It wasn’t until the discovery of the Rapid Eye Movement (REM) state that scientists really looked into what happens in the brain while we are asleep. Studies have found that we go through a cycle of stages during sleep, and it is important for our health (Orientation to Topic). Today, I am going to inform you about what really happens when we sleep, and some issues that are found among it (Specific Purpose). In order to really understand this worldwide commonality, you need to know some background on sleep, the stages in the cycle, and some common disorders (Central Idea). I have taken a year long psychology course that went into depth on sleep psychology, and I have done extensive research on the topic to better grasp it (Statement of Credibility). I want to inform you on sleep so you can understand what happens when you close your eyes every night, and so you can detect any irregularities in your sleep pattern (Statement of Goodwill). First, I will give a background of why and how we know to sleep, then I will explain the stages in the sleep cycle, and finally I will tell you about some common disorders (Preview).

Like all other species, we are no different than other animals that need sleep in order to function throughout the day. However, there are other animals that do not need sleep,

Sleep is undoubtedly one of the most essential requirements for the human body to function properly. It plays a very important role in ensuring the wellness of the human body both physically as well as mentally. In fact, the importance of sleep is clear from the fact that it helps you in maintaining a good lifestyle throughout our entire lifetime. Not only does it help maintain our physical and mental health; rather it also helps in maintaining a decent and healthy lifestyle along with ensuring safety from a number of fatal diseases. It is usually said that the mood in which you wake up is largely dependent on the type of sleep you have been in. This in itself is a big proof of the importance of sleep in our lives. While sleeping, our body finally gets its share of rest and it also gets ample time in rejuvenating from all the wear and tear that it went through during the entire day. Not only this, the body is in its own working condition when we are sleeping as this is the time when it supports the healthy functioning of the brain as well as physical attributes of our body.

Sleep is defined as a complex and reversible condition where the body undergoes a period of unresponsiveness to external stimuli. Its main feature is the behavioral quiescence and the reduced unresponsiveness to stimulus on the exterior surfaces. Sleep is triggered and controlled by the central nervous system that uses networks of various neurotransmitters that are localized at a particular region in the brain. The neurotransmitters networks are redundant and any interference with a specific localized networks tampers with the sleep condition (Holtbernd, 2014). In spite the fact that sufficient proof on the functions of sleep is still unclear, it is unquestionable that sleep is a vital component in the development and normal functioning of

Sleep is a state of consciousness in which the brain has patterns of brain activity and inactivity. During sleep, a person is unresponsive to their environment and has little physical mobility. Sleep is divided into stages of sleep, determined by amount of brain activity. We study it because no one is sure why people sleep. With the development of the EEG, we have been able to track brain activity

Animal sleep is presented in various patterns like hibernation, nocturnal activity, and even napping! For example, penguins rarely sleep in case of abrupt attacks of predators. They sleep in standing positions for only a few minutes to provide security. In some occasions, penguins take naps in the ocean after a full meal. In contrast, brown bats spend generally nineteen hours just on sleeping hanging upside down. As these examples demonstrate, the state of sleeping in animals is confirmed based on scientific research. The evidence of animal sleep is obvious, mainly characterized by temporary unconsciousness, non-responsiveness to external stimuli, and passivity in movement. Although animal sleeping is corroborated by these common symptoms,

Neil Stanley once said, “Sleep is a selfish thing to do.” Sleep is defined as a natural state of rest for the body and mind. A person spends at least 1/3 of his or her lifetime asleep. When one sleeps, the brain goes through a process that is necessary in learning, memory, and creativity in ways that scientists do not fully understand. Sleep also protects the body and restores energy.

Introduction: In order to stay healthy and to function efficiently, living things must coordinate their internal processes with the external world. The most obvious feature of our environment that most creatures have to respond to is the daily cycle of light and dark. Biological processes that follow this 24-hour cycle, such as our sleep-wake cycle, are said to follow a circadian rhythm. One of the best-known circadian rhythms in humans is the daily change in body temperature. We tend to be at our coolest in the early morning and at our warmest in the late afternoon and early evening. Other circadian rhythms include hormone levels, alertness, muscle strength, and heart rate. The controlling regulator for these cyclic processes within the body is thought to be the hypothalamus, which is in the brain.

Sleeping is extremely important for all mammals, but humans especially. Without sleep we are unable to function properly and at our fullest abilities. When we sleep we grow, and it is an opportunity for us to dream which has many benefits. Sleep is also a way for us to relieve ourselves of stress.

A typical night’s sleep is much more complicated than just closing your eyes and waking in the morning. As humans, we live our life on a circadian rhythm. This means that changes occur roughly based upon a 24-hour basis. This circadian rhythm plays a major role in when we get tired and decide it’s time to sleep. This rhythm is theorized to have helped us stay safe thousands of years ago. We would fall asleep during the time that their seemed to be threats roaming around in the dark. to Once we finally get to sleep, our brains and bodies are doing much more than laying in complete stillness. There are five distinct stages of sleep that we experience as we sleep. Each is uniquely different and serves a purpose throughout the night. The first stage of sleep is a very light sleep that lasts for 5 to 10 minutes. During this stage of sleep, you may not even realize that you’re sleeping. While in this stage of sleep our brains power down by 50 percent and produce theta waves four to seven times per second. We proceed to stage two after this. During stage two, our brains power down