LACK OF SLEEP

DO YOU TAKE ENOUGH SLEEP?

WHAT IS SLEEP?• Sleep is a naturally recurring state of body characterized by reduced or no consciousness, relatively suspended sensory activity, and inactivity of nearly all voluntary muscles. It is distinguished from quiet wakefulness by a less ability to react to stimuli. Sleep is also a heightened anabolic state, accentuating the growth and rejuvenation of the immune, nervous, skeletal and muscular systems. It is observed in all mammals, all birds, and many reptiles, amphibians, and fish.

• The purpose and mechanism of sleep are only partially clear and are the subject of research. Sleep timing is controlled by the circadian clock, Sleep –wake homeostasis, and in humans, within certain bounds, willed behavior. The circadian clock—an inner timekeeping, temperature-fluctuating, enzyme-controlling device works in tandem with adenosine, a neurotransmi--tter that inhibits Many of the bodily processes associated with wakefulness. Adenosine is created over the course of the day; high levels of adenosine lead to Sleepiness, Optimum time of sleeping recommended is 8 hrs.

Scientists have shown numerous ways in which sleep is related to memory. In a study conducted by Turner, Drummond, Salamat, and Brown, working memory was shown to be affected by sleep deprivation. Working memory is important because it keeps information active for further processing and supports higher-level cognitive functions such as decision making, reasoning, and episodic memory. The study allowed 18 women and 22 men to sleep only 26 minutes per night over a four-day period. Subjects were given initial cognitive tests while well-rested, and then were tested again twice a day during the four days of sleep deprivation. On the final test, the average working memory span of the sleep-deprived group had dropped by 38% in comparison to the control group. Wound healing has been shown to be affected by sleep. A study conducted by Gumustekin et al. In 2004 shows sleep deprivation hindering the healing of burns on rats. There are many reasons for poor sleep. For example, excessive exposure to bright light within hours of bedtime or simply resisting the urge to fall asleep can trigger a "second wind," which then can temporarily make it difficult to fall asleep afterwards.

Dreaming

Dreaming is the perceived experience of sensory images and sounds during sleep, in a sequence which the dreamer usually perceives more as an apparent participant than as an observer.

TYPES OF SLEEPREM (Rapid Eye Movement)• Rapid eye movement sleep, or REM sleep, accounts for 20–25% of total sleep time in most human adults. The criteria for REM sleep include rapid eye movements as well as a rapid low-voltage EEG. Most memorable dreaming occurs in this stage. At least in mammals, a descending muscular atonia is seen. Such paralysis may be necessary to protect organisms from self-damage through physically acting out scenes from the often-vivid dreams that occur during this stage.

NREM (Non-Rapid Eye Movement)• Stage N1:- It refers to the transition of the brain from alpha waves having a frequency of 8–13 Hz to theta waves having a frequency of 4–7 Hz.

• Stage N2:- It is characterized by sleep spindles ranging from 11 to 16 Hz and K-complexes. This stage occupies 45–55% of total sleep in adults.

• Stage N3:- It is characterized by the presence of a minimum of 20% delta waves ranging from 0.5–2 Hz and having a peak-to-peak amplitude >75 μV.

SLEEP IN NON-HUMANS• Neurological sleep state can be difficult to detect in some animals. In these cases, sleep may be defined using behavioral characteristics such as minimal movement, postures typical for the species, and reduced responsiveness to external stimulation. Herbivores, who require a long Waking period to gather and consume their diet, typically sleep less each day than similarly sized carnivores, who might well consume several days supply of meat in a sitting.

• Horses  can sleep while standing. Giraffes. Bats sleep while hanging upside down. Some aquatic mammals and some birds can sleep with one half of the brain sleeping while the other half is awake, so-called unihemispheric slow-wave sleep. Many mammals sleep for a large proportion of each 24-hour period when they are very young. However, killer whales and some dolphins do not sleep during the first month of life. 

OPTIMAL AMOUNT OF SLEEP

SLEEP DEBTSleep debt is the effect of not getting enough rest and sleep; a large debt causes mental, emotional and physical fatigue. Sleep debt results in diminished

abilities to perform high-level cognitive functions. Neuro-physiological and functional studies have demonstrated that frontal regions of the brain are particularly responsive to homeostatic sleep pressure.

EXPERTS SAY THE INDIRECT COSTS OF SLEEP DISORDERS TOP $100 BILLION A YEAR.

Age And Condition Average Amount Of Sleep

Newborn  Upto 18 hoursOne year old 14-18 hoursOne to three year old 12-15 hoursThree to five year old 11-13 hoursFive to twelve 9-11 hoursAdolescents 9-10 hoursAdults 7-8 hours

How To Sleep Well

•  Nothing is more frustrating than not being able to sleep. Tossing and turning. Your mind is racing, going over everything that happened today. Night noises keep you awake. What can you do? There are things you can do! Read on and learn some new tricks to sleep well. These tips are also known as "Sleep Hygiene." £ Sleep only when sleepy£ Don't take naps£ Get up and go to bed the same time every day£ Refrain from exercise at least 4 hours before bedtime£ Only use your bed for sleeping£ Stay away from caffeine, nicotine and alcohol at least 4-6 hours before

bed£ Have a light snack before bed£ Take a hot bath 90 minutes before bedtime

SLEEP DISORDERS

Almost everyone occasionally suffers from short-term insomnia. This problem can result from stress, jet lag, diet, or many other factors. Insomnia almost always affects job performance and well-being the next day. About 60 million Americans a year have insomnia frequently periods of time, which leads to even more serious sleep deficits. Insomnia tends to increase with age and affects about 40 percent of women and 30 percent of men.

• Transient insomnia lasts for less than a week. • Acute insomnia is the inability to consistently sleep well for a period of less than a month. • Chronic insomnia lasts for longer than a month.

• Sleep Apnea• Sleep apnea is a disorder of interrupted breathing during sleep. It usually occurs in association with fat build-up or loss of muscle tone with aging. These changes allow the windpipe to collapse during breathing when muscles relax during sleep.

• Restless legs syndrome (RLS), a familial disorder causing unpleasant crawling, prickling, or tingling sensations in the legs and feet and an urge to move them for relief, is emerging as one of the most common sleep disorders, especially among older people.

• Narcolepsy• Narcolepsy affects an estimated 250,000 Americans. People with narcolepsy have frequent "sleep attacks" at various times of the day, even if they have had a normal amount of night-time sleep. These attacks last from several seconds to more than 30 minutes.

Insomnia

Types of insomnia

Sleep Apnea

Restless Legs Syndrome

Narcolepsy

SLEEP DEPRIVATION

• Sleep deprivation is the condition of not having enough sleep; it can be either acute orchronic. A chronic sleep-restricted state can cause fatigue, daytime sleepiness, clumsiness and weight loss or weight gain. It adversely affects the brain and cognitive function. Few studies have compared the effects of acute total sleep deprivation and chronic partial sleep restriction. Generally, lack of sleep may result in:

• aching muscles• depression• headaches• bloodshot eyes• increased blood pressure• increased stress hormone levels• increased risk of diabetes, fibromyalgia• irritability• nystagmus (rapid involuntary rhythmic eye movement) • obesity• yawning• confusion, memory lapses or loss• Lack of sleep ups risk of colon cancer

EFFECTS OF LACK OF SLEEP

EFFECTS ON THE BRAIN

• Sleep deprivation can adversely affect the brain and cognitive function. A 2000 study, by the UCSD School of Medicine and the Veterans Affairs Healthcare System in San Diego, used functional magnetic resonance imaging (fMRI) technology to monitor activity in the brains of sleep-deprived subjects performing simple verbal learning tasks. The study showed that regions of the brain's prefrontal cortex displayed more activity in sleepier subjects. Depending on the task at hand, the brain would sometimes attempt to compensate for the adverse effects caused by lack of sleep.

EFFECTS ON THE HEALING PROCESS

• A 1999 study found that sleep deprivation resulted in reduced cortisol secretion the next day, driven by increased subsequent slow-wave sleep. Sleep deprivation was found to enhance activity on the hypothalamic-pituitary-adrenal axis (which controls reactions to stress and regulates body functions such as digestion, the immune system, mood, sex, or energy usage) while suppressing growth hormones. The results supported previous studies, which observed adrenal insufficiency in idiopathic hypersomnia.

EFFECTS ON GROWTH

• A study conducted in 2005 showed that a group of rats which were deprived of REM sleep for five days had no significant effect on their ability to heal wounds, compared to a group of rats not deprived of "dream" sleep. The rats were allowed deep (NREM) sleep. However, another study conducted by Gumustekin et al. in 2004 showed sleep deprivation hindering the healing of burns on rats.

ATTENTION AND WORKING MEMORY

• Among the numerous physical consequences of sleep deprivation, deficits in attention and working memory are perhaps the most important; such lapses in mundane routines can lead to unfortunate results, from forgetting ingredients while cooking to missing a sentence while taking notes. Working memory is tested by such methods as choice-reaction time tasks.

IS IT A SLEEP DISORDER?

Do you . . .

Often get told by others that you

look tired?

Feel irritable or sleepy during the day?

Feel like you have to take a

nap almost every day?

Have difficulty staying awake

when sitting still, watching

television or reading?

Have difficulty concentrating

If you answered “yes” to any of the previous

questions, you may have a sleep disorder.

Fall asleep or feel very tired while

driving?

React slowly?

MYTHS AND FACTS ABOUT SLEEP

Myth: The older you get, the fewer hours of sleep you need.Fact: Sleep experts recommend a total sleep time of seven to nine hours of sleep for the average adult. Sleep patterns change as

people age, but the amount of sleep they generally need does not. Older people may wake more frequently through the night and may actually get less night time sleep, but their need for sleep is no less than that of younger adults. Older people tend to

sleep more during the day because they may sleep less during the night.

Myth:-You can "cheat" on the amount of sleep you get.Fact: Sleep experts say that most adults need between seven and nine hours

of sleep each night for optimum performance, health, and safety.

Myth: - Teens who fall asleep in class have bad habits and/or are lazy.

Fact: Teens need at least 8.5 – 9.25 hours of sleep each night, compared to an average of seven to nine hours each night for most adults. The internal biological clocks of teenagers can keep them awake later in the evening and can interfere

with waking up in the morning.

Myth: - Daytime sleepiness always means a person is not getting enough sleep.

Fact: Excessive daytime sleepiness can occur even after a person gets enough sleep. Such sleepiness can be a sign of an underlying

medical condition or sleep disorder such as narcolepsy or sleep apnea. Symptoms should be discussed with a physician.

Myth: - During sleep, your brain rests.Fact: The body rests during sleep. Despite this fact, the brain remains active, gets "recharged," and still controls many body functions including breathing.

THANK YOU

HAVE A GOOD SLEEP TONIGHT