Sleep and Consciousness

Question 1

States of Consciousness - Consciousness

Answer 1

• Is awareness of our self and environment.
• Can have different levels of consciousness (diff levels of awareness) and can be natural or be induced by external factors such as drugs or internal such as mental efforts.
• States range from alertness to sleep.

Question 2

States of Consciousness - Alertness

Answer 2

You’re awake, aware of who you are, what’s going on in the environment, focus your attention, engage in conformation, code info to your memory.

Question 3

States of Consciousness - Daydreaming

Answer 3

• Feel more relaxed, not as focussed as alertness.
• Can also be light meditation

Question 4

States of Consciousness - Drowsiness

Answer 4

• Just before falling asleep/after waking up.
• Can also be self-induced in deep meditation.

Question 5

States of Consciousness - Sleep

Answer 5

Not aware of self or world around you.

Question 6

Electroencephalograms (EEGs)

Answer 6

• Can measure brainwaves.
• 4 main types:

1. Alpha
2. Beta
3. Delta
4. Theta

• Each type oscillates at diff frequency and associated with different type of consciousness.

Question 7

Beta Waves (12-30Hz)

Answer 7

Associated with awake/concentration.

Question 8

Alpha Waves (8-13 Hz)

Answer 8

• In daydreaming state. Lower frequency than beta waves.
• Disappear in drowsiness but reappear later in deep sleep.

Question 9

Theta Waves (4-7Hz)

Answer 9

• Slower/lower frequency than alpha waves.
• Drowsiness/right after you fall asleep/when you are sleeping lightly.

Question 10

Dealta Waves (0.5-3Hz)

Answer 10

• Slower/lower frequency than theta waves.
• Deep sleep or coma.

Question 11

Sleep Stages

Answer 11

• Your brain goes through distinct brain patterns during sleep.
• 4 main stages that occur in 90 min cycles.
• First three stages are categorized in non-rapid eye movement sleep (non-REM) – N1, N2, N3

Question 12

N1 (Stage 1 of Sleep)

Answer 12

Dominated by theta waves.

Question 13

Hypnagonic Hallucinations (Stage 1 of Sleep)

Answer 13

• Hearing or seeing things that aren’t there
• Example: seeing flash of light, or someone calling your name, doorbell, etc.

Question 14

Tetris Effect (Stage 1 of Sleep)

Answer 14

• If you play Tetris right before bed, you might see visual images of blocks during sleep.
• Example: Been on a boat all day, you might still feel like you are on water even when on dry land

Question 15

Hypnic Jerks (Stage 1 of Sleep)

Answer 15

• Muscle twitches you sometimes experience as you fall asleep.
• Feeling of falling.

Question 16

N2 (Stage 2 of Sleep)

Answer 16

• Deeper stage of sleep.
• People in N2 are harder to awaken.
• We see more theta waves, as well as sleep spindles and K-complexes.

Question 17

Sleep Spindles (Stage 2 of Sleep)

Answer 17

Sleep spindles in some parts of brain associated with ability to sleep through loud noises.

Question 18

K-Complexes (Stage 2 of Sleep)

Answer 18

• Supress cortical arousal and keep you asleep.
• Also help sleep-based memory consolidation (some memories are transferred to long term memory during sleep, particularly declarative/explicit memories).

Question 19

N3 (Stage 3 of Sleep)

Answer 19

• Slow wave sleep.
• Very difficult to awaken.
• Characterized by delta waves.
• Where sleep walking/talking in sleep happens.
• Declarative Memory consolidation.

Question 20

REM (Rapid-Eye Movement) Stage

Answer 20

• Eyes move rapidly beneath your eyelids but most of your other muscles are paralyzed.
• Most important for memory consolidation.
• Formation of episodic memories.
• Combination of alpha, beta, and dyssynchronous waves, similar to beta waves seen when awake.
• Acronym: BATS-Drink Blood (beta, alpha, theta, ,sleep- spindle/K-complex delta beta)

Question 21

Order of Sleep Cycle

Answer 21

• N1 -> N2 -> N3 -> N2 -> REM -> N1
• Cycle through these 4-5 times per sleep, each one 90 minutes.

Question 22

Circadian Rhythms

Answer 22

• Controlled by melatonin, produced in the pineal gland.
• Why you get sleepy in afternoon? They’re our regular body rhythms across 24-hour period.

Question 23

Prefrontal-Cortex in REM Sleep

Answer 23

• Activity is decreased here. (Part responsible for logic)

Question 24

Sigmund Freud - Why do Dreams Occur?

Answer 24

Dreams are our unconscious thoughts and desires that need to be interpreted.

Question 25

Evolutionary Biology - Why do Dreams Occur?

Answer 25

Threat simulation, to prepare for real world.

Question 26

Sigmund Freud’s Theory of Dreams

Answer 26

Says dreams represent our unconscious feelings/urges/thoughts.

Question 27

Activation Synthesis Hypothesis (Dreams)

Answer 27

• Brain gets a lot of neural impulses in brainstem, which is sometimes interpreted by the frontal cortex.
• Brainstem = Activation
• Cortex = Synthesis
• Our brain is simply trying to find meaning from random brain activity.
• Therefore dreams might not have meaning.

Question 28

Disorders: Sleep Deprivation

Answer 28

• Irritability and poorer memory and attention.
• Susceptible to obesity – body makes more cortisol, and the hunger hormone (ghrelin).
• Increase your risk for depression.

Question 29

Disorders: Insomnia

Answer 29

• Persistent trouble falling asleep or staying asleep.

Question 30

Disorder: Narcolepsy

Answer 30

• Can’t help themselves from falling asleep.

Question 31

Disorders: Sleep Apnea

Answer 31

• Stop breathing while sleeping,
• Body realizes you’re not getting enough oxygen, wake up just long enough to gasp for air and fall back asleep without realizing.
• Can happen 100x/night!
• Don’t get enough N3 (Stage 3; slow-wave) sleep.
• Snoring is an indication, or fatigue in morning after full night of sleep.

Question 32

Disorders: Sleepwalking

Answer 32

• Mostly genetic, occur during N3 (stage 3; slow wave) and are harmless.
• Occur more often in children (partly because they have more N3 stage sleep than adults).

Question 33

Induced States of Consciousness

Answer 33

• Hypnosis + medication are examples.
• Does not occur naturally.

Question 34

Hypnotism

Answer 34

• Usually involves getting person to relax and focus on breathing, and they become more susceptible to suggestion in this state – but only if they want to.
• More alpha waves in this stage – an awake but relaxed state.

Question 35

Meditation

Answer 35

• Training people to self-regulate their attention and awareness.
• Can be guided and focused on something in particular, like breathing, but meditation can also be unfocussed – mind wanders freely.
• More alpha waves than normal relaxation in light meditation.