Chapter 12 - sleep

what 'sets' the biologicals clock

(SCN) - suprachiasmatic nucleus located just above the optic chiasm - when it gets dark outside (light) light is what sets out clocks

Theories about why we sleep

1. As an evolutionary protective mechanism - night vision not great 2. Sleep is a restorative function idea when we are sick we sleep more, work out, cognitive or emotional 3. Growth may occur during sleep. The growth hormone is highest in the dark at night.

Stages of sleep (5)

1. Lightest Sleep (NREM)- just fallen asleep brain waves are still active and muscle tension. Hypnagogic hallucinations - a form of dreaming, dreaming light - not connected to reality. Lots of twitching a movement 2. Slightly Deeper Sleep (NREM) brain waves gets a bit slower but they're fluctuated by two brain patterns. K-complex - specific EEG brainwave output looks like a cursive K. sleep spindles - brainwaves are slowing down and then you get a quick burst of activity it looks like a scribble on the EEG output. Sleep talking in stage 2 Postural and muscle tension is decreasing. 3. Slower-wave sleep - Deeper Sleep (NREM) no Postural and muscle tension. As asleep as you can get your brain waves are very slow. 4. Slower-wave sleep - no Postural and muscle tension. As asleep as you can get your brain waves are very slow. Delta Waves are omitted but there is not much difference between this stage and stage 3 (NREM) Sleepwalking Bedwetting 5. REM

Narcolepsy - fall asleep when you don't want to be.

1. Narcolepsy Not as uncommon as you might think - 1 in 1000 Associated with cataplexy loss of muscle tone, sleep paralysis, & hypnagogic hallucinations, light dreaming. Different forms of Narcolepsy 2. Attacks are often brought on by emotions, super happy, super sad. 3. Cause may be linked to neurotransmitter problems, neurohormone - ACh (stem) & Hypocretin (hypothalamus)

Night Terrors, etc.

1. Night terrors are different from your typical nightmare Children under the age of 6 panic attack in the stage 4 sleep cycle. 2. Sleepwalking often runs in families

Why REM why we have it? what does it do for us?

1. REM is necessary, without it we become irritable and ADD-like, slowed reaction time 2. Maybe involved in learning and memory REM sleep is disrupted The consolidation short term to long term memory process is a good candidate Research is mixed 3. Weird Eyeball theory - eyes health - laying down for long periods of time, not good circulation shake eyeballs to put blood in the retina.

How much sleep do we need?

1. The answer varies based on factors such as age Newborns 80% of the day 2 to 3 yr - 15 hours 3yr - 10 -12 a night Puberty - Teenagers increase the need for sleep. 12 hours and naps Older adults 7-9 hours - better cognitive and physical health. 2. Most adults allowed to sleep as long as they like will tend to go about 7 - 9 hours

REM behavior disorder (RBD)

1. This is a relatively newly recognized disorder Occurs most frequently in older men with other brain disorder (like Parkinson's/Alzheimer's) 2. It has been used as a defense for 'sleep-walking crime'

Treatments for Insomnia

1. What have you guys tried when you can't sleep? 2 .Sleeping pills and alcohol - issue altering brain active not getting sleep. Poor quality of sleep. 3. Insomnia is often a behavioral issue & can be fixed with behavioral interventions Napping no naps 20 minutes or less never after 4 pm turn your brain off before bed - no studying exercising at night (wakeful more mental energy) Caffeine - as you age our body gets more sensitive to caffeine. Soda, chocolate, tea, etc. avoid them. The bed is just for sleeping - just for sleeping - so you can fall asleep.

Narcolepsy treatment

1. You'd think treatments would focus on the proposed causes, right? What would this entail? Why can't we do that? hypothalamus 2. Treatment at this point is basically to load these folks up with stimulants

restless leg syndrome (RLS)

1. Your book calls this 'periodic limb movement disorder 2. It is where as you are falling asleep your legs kick involuntarily, waking you up 3. Pharmacological interventions

restless leg syndrome (RLS)

1. Your book calls this 'periodic limb movement disorder' 2. It is where as you are falling asleep your legs kick involuntarily, waking you up 3. Pharmacological interventions

How do we get to sleep

1.Decreasing stimulation - taking in less information from our sensory systems. Decreases the amount of information coming into our minds. (white Noise) 2.Temperature changes our body temperature drops by 2 10th of a degrees. 3.Inhibit the arousal centers of the brain, namely the forebrain- Brain has to start slowing down power down in the forebrain. emotional centers and prefrontal cortex - executive functions

Treatments for Sleep Apnea

1.Weight loss 2.Alcohol/depressants 3.Oxygen Delivery Mask 4.Surgery Kids - adenoids/tonsils Adults - excess tissue

Slower-wave sleep stage 3 & 4

3. Slower-wave sleep - Deeper Sleep (NREM) no Postural and muscle tension. As asleep as you can get your brain waves are very slow. 4. Slower-wave sleep - no Postural and muscle tension. As asleep as you can get your brain waves are very slow. Delta Waves are omitted but there is not much difference between this stage and stage 3 (NREM) Sleepwalker Bedwetting

Why Dreams?

Activation synthesis hypothesis Clinico Anatomical

What is Sleep

Can anyone describe it to me? Sleep is good people love it, what is it behavioral? Sleep is a periodic necessary and reversible loss of consciousness. Lay down and turn off for several hours per day. Sleep has a distinct biological rhythm another Endogenous cycle About every 90 minutes we cycle through 5 stages of sleep

shift work

Can we effectively override the circadian rhythm and shift our bodies to be awake at night and sleep all day. A pattern of work in which you sometimes work during the day and sometimes during the night More mistakes during the night.

1.Can you think of any circumstances where you would want to manipulate the Biological clock? Shift your Endogenous Cycles your awake a little earlier or stay up a little later.

Daylight saving time and traveling over time zones - jeg lag

Function of melatonin hormone

Help you fall asleep -Endogenous Cycles- 2 hours before your natural bedtime, fall asleep your pineal gland has released melatonin into your bloodstream.

Can we Manipulate the biological clock

Humans are Diurnality animals - awake during the day - not nocturnal

Insomnia (inability to sleep)

Insomnia, three kinds: 1. ONSET insomnia - difficulty falling asleep. Inability to fall asleep, you feel really tired and can't fall asleep. 2. MAINTENANCE insomnia - fall asleep fine but wake up at some later time throughout the night. Then you have difficulty falling back to sleep. 3. TERMINATION insomnia - fall asleep you stay asleep for most of the night nut up wake up early 2 hours or more and still feel tired but can't fall back to sleep. Different types of Insomnia are linked to different psychological disorders (mental illness). Screw-ups in the body's temperature change are associated with onset at termination insomnia 1. Phase delayed - temperature change normal temperature is not falling results to Insomnia. 2. Phase advanced - body temperature rises too quickly and wakes up - Termination Insomnia 90% of sleep issues are behavioral issues

How we cycle through sleep

It doesn't go 1-2-3-4- REM In other words, the '5th stage' of sleep doesn't happen right after stage 4! We cycle down 1, 2,3, 4 and then back up4, 3, 2, and then have REM instead of stage 1 We don't spend equal amounts of time in each stage during the night. 100 minutes changes depending on the stage of the night that you are. 2nd or 3rd majority of time spent in the slow-wave sleep cycle. Closer to the morning more time in REM cycle Sleep deprive - more time in REM cycle

Dr. Siegel's brain-shiver theory intriguing. But he wanted to see it put to the test.

Neuroscientists have identified a clump of neurons in the brain stem (suprachiasmatic nucleus) as the switch that turns on R.E.M. sleep. Dr. Siegel's theory predicts that in fur seals the brain stem stays warm at sea but cools on land.

The '5th' Stage of sleep REM

REM sleep - rapid eye movement, biologically distinct brain activity during the sleep cycle. We know that REM starts because of activity in the pons Hindbrain part of the brain stem. Pons (sensory) sends a message to the thalamus (sleep activity) which send the message back to the occipital lobe( visual activity) is what 'triggers' REM sleep (Looks like stage one a lot of activity) There is a pattern of brain activity from the pons to the thalamus and then to the occipital cortex. The High activation of the limbic system (emotional and memory) is also activated during REM. Vivid dreaming occurs during the REM cycle Muscle activity - paralyzed

Hormone control - Melatonin- Pineal gland

Releases melatonin

New REM Theory - seals

Seals provide evidence that our brains switch to R.E.M. sleep from time to time to generate heat in our skulls. "R.E.M. sleep is like shivering for the brain," A more telling clue about R.E.M. sleep can be found in human behavior, Dr. Siegel thinks. When people wake up on their own, they tend to move out of R.E.M. sleep and become alert. Those awakened from slow-wave sleep are groggy and disoriented. Dr. Siegel and his colleagues propose that the brain cools during slow-wave sleep. To keep the brain from getting too cold, however, the brain periodically unleashes a torrent of activity. Oxygen-rich blood flows into the brain to fuel the activity, warming the brain in the process. It keeps the brain temperature within a functional limit by cycling on and off the same way your heater in your house might do at night," Dr. Siegel said.

sleep apnea

Sleep apnea- can't breathe while you are sleeping. 1. You are basically waking up every few minutes 60 to 90 seconds all night, every night 2. You never feel rested 3. Your family will often tell you that you snore Often caused by obesity, related to heart damage

activation-synthesis hypothesis dreaming

Sleep reversible - Story explanation that states that dreams are created by the higher centers of the cortex to explain the activation by the brain stem of cortical cells during REM sleep periods The activation-synthesis model suggests that dreams are caused by the physiological processes of the brain. While people used to believe that sleeping and dreaming was a passive process, researchers now know that the brain is anything but quiet during sleep.

Hypnagogic hallucinations occur when:

Stage one sleep stage - a form of dreaming, dreaming light - not connected to reality.

Brain - suprachiasmatic nucleus

a cluster of neurons in the hypothalamus in the brain that governs the timing of circadian rhythms - biological clock Changes the way our body functions throughout a 24-hour period Damage your body stops functioning on that 24-hour clock - rare in humans (TBI) Hamsters 23-25 hour clock

jet lag

a disruption of circadian rhythms due to crossing time zones you feel sick and sleepy and hungry hard time concertation and slowed reaction time. Body interprets jet lag as a stressor.

Endogenous Cycles-

an internal process that governs the way your body functions. An example of this is a circannual rhythm - round or about annual means a year. Internal biorhythm that governs the way an animal functions throughout the year. hibernation bird migration

sleep cycle

biological rhythm - a period of sleep lasting about 90 minutes to 100 and including one or more stages of NREM sleep, followed by REM sleep Sleep cycle 5 stages of sleep- About every 90 minutes we cycle through 5 stages of sleep

Most animals, including humans have a circadian rhythm

biological rhythm that is happening inside of your body that changes the way your body functions within a daily timeframe.

Stage 2 - Slightly Deeper Sleep (NREM)

brain waves gets a bit slower but they're fluctuated by two brain patterns. K-complex - specific EEG brainwave output looks like a cursive K. sleep spindles - brainwaves are slowing down and then you get a quick burst of activity it looks like a scribble on the EEG output. Sleep talking in stage 2 Postural and muscle tension is decreasing

Let Lag

cortisol stress hormone is released into the bloodstream. 1.Constantly adjusting and re-adjusting can actually be bad for the body. Negative health effects on your body.

Stage 1 sleep stage - Lightest Sleep (NREM)

just fallen asleep brain waves are still active and muscle tension. Hypnagogic hallucinations - a form of dreaming, dreaming light - not connected to reality. Lots of twitching a movement

NREM sleep

non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep

Dr. Siegel's brain-shiver theory intriguing

seals - a half-brain style of sleeping, perhaps as a way to remain alert enough to avoid predators and drowning. Because part of the brain is always active, it's always warm. As a result, it never triggers R.E.M. sleep. Only when fur seals return to land and switch to sleeping with their entire brains do the organs cool enough to flip the switch.

Endogenous Cycles- circadian rhythm -Biological Clock

the Biological Clock governed inside the human body Brain areas External influences Neurotransmitters Hormones Glands

New REM Theory

the hypothesis that REM sleep may serve to reverse the reduced brain temperature and metabolism effects of bilateral nonREM sleep, a state that is greatly reduced when the fur seal is in the seawater, rather than REM sleep being directly homeostatically regulated.

clinico-anatomical hypothesis of dreaming

the hypothesis that dreams represent the brain's effort to make sense of sparse and distorted info. the way we use our brain during the day is how we use it during sleep. Sifting through information, learning and memory.

Hormone control - Melatonin

the suprachiasmatic nucleus (SCN) controls the glands that release hormones involved in your -Endogenous Cycles - Pineal gland - the release of melatonin