Lecture18 Consciousness

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What is Consciousness? Chapter 5-Consciousness

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Lecture18 Consciousness

Transcript of Lecture18 Consciousness

  • What is Consciousness?

    Chapter 5-Consciousness

  • Class ObjectivesWhat is consciousness?

    What are the stages of sleep?

    How does sleep deprivation effect us?

  • How would YOU define consciousness?Consciousness is a state of awareness and responsiveness

    Events in the environment

    Your own mental processes and inner awareness

    Example: Your knowledge of your feelings, thoughts, and memories.

  • Is consciousness a black or white state?No, Consciousness is a spectrum that ranges from low to high levels of awareness.

    LOWHIGHAwake

  • Feeling Sleepy?How many hours do you sleep a night?

  • What do you know about sleep?True or false?Teens who fall asleep in class have are just lazy.

    Health problems such as obesity, diabetes, hypertension, and depression are unrelated to the amount and quality of a person's sleep.

    The older you get, the fewer hours of sleep you need.

    During sleep, your brain is very active. If you wake up in the middle of the night, it is best to lie in bed, count sheep, or toss and turn until you eventually fall back asleep. False! 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. False!True!False!False!

  • Did you know?

    Did you know that we spend about 1/3 of our lives asleep. If you live to be 75 years old you will have slept about 25 years!

    An average 20 year old student has spent about 6 years asleep!

  • Researchers have established what happens during sleep, but not why we sleep.

    One theory is that we sleep because we are tired. In other words, sleep has a restorative function, like rebooting a computer.

  • Is it important to maintain a regular bed and wake time?

  • Biological ClockHumans and other animals have an internal biological clock called the circadian rhythms

    These patterns vary over approximately a 24-hour cycle and occur even in the absence of normal cues about whether it is day or night

    Responsible for body functions including:Hormone levelsSleep and wakefulnessBlood pressureBody temperature

  • Generated by the suprachiasmatic nucleus (SCN)

    Regulates the pineal glands secretion of the hormone melatonin

    Increases in melatonin produce drowsiness

    The Brains Control of Circadian Rhythms

  • Can your clock get out of whack?Yes, problems can occur if someone works through the night and sleeps during the day

    Also experienced with jet lagWe are awake when out circadian rhythm cries SLEEP!

    To speed up resetting your biological clock after a long flight spend time outdoorsBright lights help reset our biological clocks

  • Morning People versusEvening PeopleMorning people awaken early and full of energy doing their best work before noonMost people over 65 are morning people

    Evening people take longer to warm up in the morning doing their best work in the afternoon or eveningMost young people are evening people

  • Isnt sleep all the same?No, the use of the EEG shows variations in brain waves which determine different stages of sleep.

    There are 5 Stages of sleep(4) Non REM and (1) REM

    During an 8 hour period, people typically progress through all 5 full cycles,

    Each cycle lasts about 90 minutes

  • Non REM SleepWhen awake, brain waves show a high frequency, low amplitude pattern

    NREM (non-rapid eye movement) sleep involves increasing bodily relaxationSlower EEG activity occursThe heart rate and respiration are slower during NREM

  • Non-REM Stages of SleepNREM brain waves are of low amplitude and are fast, with mixed frequencies

    Brain activity changes with each stage

    People become more difficult to awaken as they progress through the four stages of NREM sleep.

  • Neural activity unsynchronizedStart of longer, slower brain activity(beginning to synchronize)Neural activity more synchronized(delta waves)Neural activity highly synchronized(delta waves)Neural activity unsynchronizedAwake

  • Non-REM SleepFall asleep

    Non-REM Stage 1

    Non-REM Stage 2

    Non-REM Stage 3

    Non-REM Stage 4Sleepers take about 30 to 40 minutes to go through the four stages of NREM sleep

  • REM SleepRapid eye movement (REM)

    This stage of sleep is characterized by high-frequency, low-amplitude brain wave activity

    Occurs only after people go through first 4 stages of NREM

  • REM SleepREM is difficult to distinguish from being awake on the basis of physiological measures

    During REM sleep breathing and heart rate increaseThe same rate as if we were awake

  • Function of REM SleepMemory storage- REM Helps consolidate memories

    Brain areas that are active during the learning of the task become active again during sleep

    Performance on tasks usually improves if you test someone a day after theyve learned the task

    As long as they get at least 6 hours of sleep

  • REM dreams tend to be longer, more vivid, and involve more detail and movement.However, dreaming occurs during all sleep stages.

    Paralysis of muscles occurs so we cannot act out our dreams.

  • What Happens When We Dont Get Enough Sleep?

  • Do YOU Get Enough Sleep?Sleep Deprivation Quiz

  • Sleep DeprivationThe longer people go without sleep the sleepier they get and the worse their performance becomes

    A fatigued, sleep deprived person may experience:Impaired concentration diminished productivityTendency to make mistakesIrritability A depressed immune systemGreater vulnerability to accidents

  • Sleep DeprivationResearch on total sleep deprivation with humans is not possible

    However, rats totally deprived of sleep die

    lose inability to regulate body temperature lose weight

  • Chapter 5-Sleep DisordersCLASS OBJECTIVES-

    What are Sleep Disorders?

    Narcolepsy InsomniaSleep apneaNight terrorsSleep walking

  • The EEG is used to help diagnose sleep disorders

  • Sleep disorders quizTrue or False?Approximately 70 million people in the United States are affected by a sleep problem.

    If you regularly doze off unintentionally during the day, you may need more than just a good night's sleep.

    If you snore loudly and persistently at night and are sleepy during the day, you may have a sleep disorder.

    Narcolepsy is a sleep disorder marked by "sleep attacks.

    The primary cause of insomnia is worry. TrueTrue TrueTrue

  • Sleep Disorders are divided into two major diagnostic categories:

    Dyssomnias and Parasomnias Approximately two-thirds of adult suffer from sleep problems, and about 25% of children under the age of 5 have sleep disturbance

  • What is Narcolepsy?

  • Sleep DisordersPeople who experience sudden, uncontrollable episodes of sleep have Narcolepsy.

    Main symptoms:Fall asleep suddenly and unexpectedlyExcessive daytime sleepiness and Abnormal REM sleep.

  • Sleep DisordersSleep apnea causes airflow into the lungs stop for at least 15 seconds.

    The sleeper stops breathing, chokes, then wakens briefly. Rather than choking awake, some choke and die (Skatrud &Pappard, 2004).

    People with this disorder can have as many as 100 episodes per night.

  • Consequences of Sleep Apnea People with sleep apnea get poor-quality sleep and feel extremely sleepy during the day.

    The person may have:Memory lossSuffer from severe headaches or work-related accidents.

    Sleep apnea may also lead to high blood pressure, heart disease, heart attack, and stroke.

  • Whos effected by this sleep disorder?This disorder is fairly common, 33% of the population experience symptoms of sleep apnea.

    Middle-aged, overweight men are at risk, but even children can have this disorder.

  • Can it be treated?Several effective therapies have been developed, including minor surgery or the use of a machine that affects airway pressure.

  • I just CANT sleep!!

    Insomnia is the most common dyssomnia effecting as many as one in ten people each year!

  • InsomniaInsomnia involves problems in going to sleep or maintaining sleep.

    10% of the population experience insomnia at sometime and is often associated with anxiety or depression.

    People with insomnia may actually sleep as much as norm, but quality of sleep tends to be poor and dont feel rested (Dement, 1999).

  • Insomnia

    People with insomnia tend to be listless and tired during the day, which often leads to the use of sleep medications.

    Drugs are not a preferred treatment due to a high link to dependence on sleeping pills and other drugs.

    Behavioral treatments for insomnia include relaxation training, cognitive therapy, and self-hypnosis.

  • Insomnia

  • Parasomnias include abnormal disturbances during sleepThese include nightmares, night terrors, sleep walking and sleep talking

  • Night TerrorsNight Terrors is a sleep disorder in which a person experiences symptoms of a panic attack

    The child can usually be seen sitting upright in state of sheer panic.Scream, breathe rapidly appear awake- yet person is not fully conscious

    This disorder is most common in children between ages 3-8 and disappears as the child grows older.

  • Are these just BAD nightmares?

    NO, they are not nightmares and they occur in NREM sleep, usually stage 3 or 4.

  • SleepwalkingSleep Disorder characterized by walking or other activity while seemingly still asleep.

    Sleepwalking is common in children 6-12 years old. It may occur at any age and it appears to run in families.

    Sleepwalking affects approximately 1% to 17% of children and is more frequently seen in boys.The incidence of sleepwalking decreases with age.

  • SleepwalkingTRUE or FALSE? Sleepwalkers are acting out dreams It is dangerous to wake a sleep walker False!False!

  • SleepwalkingSleepwalkers are NOT acting out a dream-brainwave activity of sleepwalkers indicate that they are in stage 4 sleep.

    There is no danger in waking a sleepwalker. most likely you cannot because they are so deeply asleep.

    *****According to sleep experts, 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. Their internal biological clocks also keep them awake later in the evening and keep them sleeping later in the morning. However, many schools begin classes early in the morning, when a teenager's body wants to be asleep.

    Studies have found a relationship between the quantity and quality of one's sleep and many health problems. For example, insufficient sleep affects growth hormone secretion that is linked to obesity; as the amount of hormone secretion decreases, the chance for weight gain increases. Blood pressure usually falls during the sleep cycle, however, interrupted sleep can adversely affect this normal decline, leading to hypertension and cardiovascular problems. Research has also shown that insufficient sleep impairs the body's ability to use insulin, which can lead to the onset of diabetes. More and more scientific studies are showing correlations between poor and insufficient sleep and disease.

    While sleep patterns change as we age, the amount of sleep we need generally does not **Yes- A regular waking time in the morning strengthens the circadian function and can help with sleep onset at night. That is also why it is important to keep a regular bedtime and wake-time, even on the weekends when there is the temptation to sleep-in. *The suprachiasmatic nucleus is part of the hypothalamus

    The suprachiasmatic nucleus serves as the primary circadian pacemaker in mammals.The SCN keeps time so well that scientists call it the biological clockIt sends messages to different parts of the brain which in turn control numerous cyclic behaviors and mechanismsThere are many behaviors in humans that occur within a 24-hr period including body temperature, levels of hormones within the bloodstream, mental alertness, and our need to sleepThe pineal gland starts releasing melatonin between 8 and 10 pm so people will fall asleep approximately 2-3 hours laterIncreases in melatonin levels correspond with increasing drowsiness*Light delays sleep!*_______ did a study on young adults (18-22 years old) and older adults (66-78 years old) tested their memories at different times of the day.When tested early in the morning, the older adults did just as well as the young adultsAs the day goes on, younger adults either remained steady or improved whereas older adults deteriorated steadily

    This effect is seen in old versus young in humans, rats, and other species

    Thinking and memory are sharpest and most accurate when you are at your daily peak in circadian arousal. It changes as we age.****Each cycle is 90 to 100 minutes in average in young adults.

    In an average nights sleep we go through about 5 sleep cycles

    The cycles continue throughout the night stages 3 and 4 get shorter as the night progresses while REM and stage 2 gets longer***Some research has found the REM sleep is correlated with the amount of new material learned on the previous day.

    Block, Hennevin, and Leconte (1978) trained rats to run a maze and then measured the duration of REM sleep each animal engaged in that nightAs soon as training started, the animals increased their overall amount of REM sleepThis amount continued to increase peaking on day 6 (which was the day that the rats made the biggest improvement in their performance)After day 6, the animals REM sleep returned to normal

    These data suggest that REM sleep may in some way be involved with processing or consolidation of new information.

    REM sleep enhances certain types of learning and problem solving. There is NO evidence that new factual learning can occur during sleep (cannot learn new words, numbers, etc..)**Sleep deprivation creates: difficulty studying, diminished productivity, tendency to make mistakes, irritability and fatigue.

    In 1958, a DJ Peter Tripp staged a 200 hour wakeathon for the benefit of the March of Dimes. Tripp broadcast his radio show without sleeping for 10 consecutive days. Toward the end, he grew dizzy, irritable, and very unhappy. He experienced speech tremors, slurred speech, and gagging. He heard voices and knew that someone was trying to poison him. When it was time to change a record or make an announcement, he concentrated long enough to do his job properly, making only an occasional strange comment on the air.

    One observer described him: By 170 hours the agony had become almost unbearable to watch. At times, Tripp was no longer sure he was himself. He frequently tried to gain proof of his identity. Although he behaved as if he were awake, his brain-wave patterns resembled those of sleep. In his psychotic delusion, he was convinced that the doctors were in a conspiracy against him to send him to jail. At the end of the 200 sleepless hours, nightmare hallucination and reality had merged, and he felt that he was the victim of a sadistic conspiracy among the doctors.****Its name comes from a Greek word, apnea, meaning "without breath******