Sleep part 2 Flashcards by Melinda Herceg

Describe a typical night’s sleep (pattern of REM and Non REM and cycles)

People undergo several sleep state changes in
roughly 90-minute periods
NREM sleep dominates early sleep periods.
* REM sleep dominates later sleep

How well did you know this?

Not at all

Perfectly

Describe how REM varies with age:

Babies –> 50% of sleep in REM
Old people –> only 10% in REM
Adults –> spend 20% in REM

How well did you know this?

Not at all

Perfectly

How does body temp change throughout sleep?

Body temp decreases during first half of night then increases in second half

How well did you know this?

Not at all

Perfectly

Describe the characteristics of NREM sleep (4):

Decrease in body temp., heart rate, blood flow, body weight. Increase in growth hormones (repair)
* Motor activity (Restless leg syndrome, teeth grinding)
* Dreaming occurs in NREM sleep, but dreams are not as vivid as in REM sleep.
* Maintain muscle posture

How well did you know this?

Not at all

Perfectly

Describe the characteristics of REM sleep (2):

Atonia - brainstem inhibits motor neurons
Some extremities and facial muscles
twitch
Mechanisms that regulate body
temperature stop working.

How well did you know this?

Not at all

Perfectly

When do vivid dreams occur?

REM

How well did you know this?

Not at all

Perfectly

Do dreams occur during NREM?

Yes, but they are less vivid

How well did you know this?

Not at all

Perfectly

Describe the characteristics of dreams

Dreams appear to take place in real time; dream sessions get longer
throughout a sleep session

How well did you know this?

Not at all

Perfectly

How often do people dream?

Everyone dreams a number of times each night.
* Some people feel that they don’t dream often – more likely they forget

How well did you know this?

Not at all

Perfectly

Why do people not remember their dreams?

NREM phase erases dream?
* Mechanisms for storage not (or less) active? –> during NREM takes a minute for hippocampus to be woken up so the brain forgets

How well did you know this?

Not at all

Perfectly

What is a theory about what we dream about?

Psychoanalytic Theories

How well did you know this?

Not at all

Perfectly

What were the two beliefs of the people involved in psychoanalytic theory?

Sigmund Freud
* Dreams are the symbolic fulfillment of unconscious wishes.
* Manifest content vs. Latent content
Carl Jung -Dreams are expressions of our collective unconscious

How well did you know this?

Not at all

Perfectly

What is manifest vs latent content?

Manifest is things we explicitly remember and latent is the underlying meaning of a dream

How well did you know this?

Not at all

Perfectly

What do experiments show about dreams?

Most dreams are related to quite recent events and concern ongoing problems.

How well did you know this?

Not at all

Perfectly

After analyzing 10k dreams what did Hill find?

64% of dreams had negative emotions
Only 18% is positive

How well did you know this?

Not at all

Perfectly

What is the contemporary approach to dream interpretation?

Bottom up: the person has a dream, then either the dreamer or a dream
interpreter analyzes it.
* Top down: The dreamer makes the dream –> goal makes you dream about something

How well did you know this?

Not at all

Perfectly

What is the bottom up theory of dreams?

Activation-synthesis (dreams as meaningless brain activity)

How well did you know this?

Not at all

Perfectly

Describe the activation synthesis theory

The cortex is bombarded with signals from the
brainstem, producing the pattern of waking EEG.
* In response, cortex generates images, actions, and
emotions from personal memory stores.
* Without external verification, these dreams are
fragmented

How well did you know this?

Not at all

Perfectly

What does PET research show about frontal lobe during dreams?

PET research suggests that frontal activation is
suppressed during dreams

How well did you know this?

Not at all

Perfectly

What is the top-down theory of dreams?

Coping hypothesis

How well did you know this?

Not at all

Perfectly

Describe the coping hypothesis of dreams

Dreams are highly organized and biased toward threatening images.
* Dreams are biologically important because they lead to enhanced performance in dealing with threatening life events (adaptive function)

How well did you know this?

Not at all

Perfectly

What is another way that dreams could be a top down process?

Dreams as problem solving mechanism

How well did you know this?

Not at all

Perfectly

What are lucid dreams

Dreamer is aware of
dream occurrence as
they are dreaming and can control their dreams

How well did you know this?

Not at all

Perfectly

What percentage of people have lucid dreams?

40-50%

How well did you know this?

Not at all

Perfectly

How often do people lucid dream? And when?

Substantial variation in lucid dreaming frequency * Typically occurs during later periods of REM sleep * Might also occur in NREM 1 and 2 but difficult to measure

What occurs in the body during lucid dreams?

increased autonomic system arousal (heart rate)

What other condition can co-occur with lucid dreaming?

Sleep paralysis and lucid dreaming can co-occur but arise due to different experiences (

Why does sleep paralysis arise? How about lucid dreams?

Sleep paralysis --> low sleep quality and life stress; Lucid dream -->positive daydreaming

What people have increases propensity to have lucid dreams?

Individuals suffering from narcolepsy have increased propensity to have lucid dreams and nightmares

What do lucid dreams provide relief from?

Nightmares

What did EEG show about brain activity during lucid dreaming?

Increased beta activity in parietal regions in lucid compared to non-lucid REM sleep * Reduced delta activity in frontal regions --> Signifying more frontal activity

What is a brain difference in frequent lucid dreamers? (3 locations)

Increased gray matter volume in frontal pole, right ACC and hippocampus in frequent lucid dreamers

What is the connectivity difference in the brains of lucid dreamers? What is their activity like?

Increased functional connectivity between aPFC and middle temporal gyrus. These regions show reduced activity in non-lucid REM sleep but increased activity during Lucid REM sleep

What can promote lucid dreaming?

ACh agonist

What are the three possibilities for what sleep accomplishes?

Biological adaptation Restorative process Memory mechanism

What is biological adaptation for sleep?

Sleep is an energy-conserving strategy. Animals with a nutrient-rich diet spend less time foraging for food and more time sleeping.

What does it mean that sleep is a restorative process?

we are tired at the end of the day, and feel refreshed with sufficient sleep. If we do not get enough sleep, we become irritable

What are the three phases of memory storage?

Encoding (labile) phase Consolidation phase Recall phase

What is the encoding phase of memory?

a new memory initially encoded Is fragile because it is competing with existing memories

What is the consolidation phase of memory?

a relatively permanent representation of the memory is solidified

What is the recall phase of memory?

The neural networks that represent the memory are activated for use

What does sleep do for memory?

sleep solidifies and organizes memory

What is the theory of NREM and explicit memory consolidation?

Synaptic homeostasis theory of sleep & memory

What is the synaptic homeostasis theory of sleep & memory?

leep allows synapses that have been active throughout the whole day to return to a quiet state during sleep * synapses that have been more active take longer to reach their resting period --> memory formation

What did the study on NREM and explicit memory consolidation show?

During the periods of NREM sleep after food search, activity of place cells is similar to food search period

What is the theory of REM sleep and implicit memory consolidation?

Sleep Memory Storage Theory

Describe the study on the Sleep Memory Storage Theory

used PET imaging to record brain activity during and after Ps performed a serial reaction time task (connect dots of screen)

What were the results of the sleep memory storage theory experiment?

PET scans during subsequent sleep show that brain regions that were active during the task are also active during REM sleep This could mean that a) Subjects were dreaming about what they learned. b) REM sleep strengthened the memory of the task

Is sleep caused by a circulating chemical in the brain? Name the chemical and what it does

Melatonin. Causes sleepiness; synthetic form can be taken as a sleep aid

What challenges that melatonin causes sleep?

removal of pineal glands does not abolish sleep * Some mammalian and avian species sleep one hemisphere at a time (melatonin doesn't just go to one side of the brain)

What is the neural basis of sleep?

RAS (reticular activating system)

Describe the study on cats?

Used EEG to record brain activity of anesthetized cats while electrically stimulating brainstem regions.

What did the study on cats find?

Discovered that cortical EEG transitioned from delta to sustained beta when a brainstem region (RAS) was stimulated. Beta activity outlasted stimulation * In sleeping (not anesthetized) cats, the stimulation awoke the cat

What does the RAS do?

Associated with sleep–wake behavior and arousal

What does stimulation and damage do to the RAS?

Stimulation of the RAS produces a waking EEG; damage to it produces a slow-wave EEG (coma)

What two pathways play a role in alertness and arousal?

Dorsal and Ventral

What does activation of cell bodies in RAS do?

can have effect on cortical activation and behaviours associated with waking

What is the dorsal pathway of the RAS for?

Arousal (heart rate, respiration)

What is the ventral pathway of the RAS for?

Alertness/ Awareness

Describe the dorsal pathway?

From brainstem --> Thalamus --> cortex

Describe the ventral pathway

From brainstem --> basal forebrain & posterior hypothalamus --> cortex

What does damage to the dorsal pathway of structure do?

Coma

What does damage to the ventral pathway or structure do?

loss of awareness in the absence of coma - vegetative state (not aware of who they are or where they are)

Sleep part 2 Flashcards

(63 cards)