Week 8: Consciousness
Definition of consciousness
- A state of awareness
- Awake vs asleep
- Content of thought
- Self awareness
Benefits of having consciousness
- Behavioral flexibility
- Greater drive to survive?
- Navigating a complex social environment
Tests for consciousness/self-awareness
- Rouge test (when can humans usually pass it?)
- Humans who are over 18 months, chimps, orangutans, asian elephants, etc
How the following brain areas are related to consciousness:
- Thalamus: relay station of the brain
- Reticular formation: reticular formation (in the brain stem). Regulates sleep and wake
cycles
Benefits of being unconscious/sleeping. What are possible reasons we evolved to sleep?
- We sleep to let the body rest and restore itself
- Sleep helps with learning and development
Examples of how altered sleep or jet lag can affect our behavior/cognitive abilities
- It disrupts the daily sleep cycles. Travelling west is easier and the more time zones you
cross increases the likelihood of jet lag
How can bright light exposure help jet lag?
- Morning: bright light advances circadian rhythm, allowing sleep to occur earlier
- Night: bright light delays circadian rhythm, allowing sleep to occur later
How do sleep requirements change with age?
- You need more sleep when you’re younger
Definition of phase delay. When does it typically occur?
- Hormones released at puberty cause phase delay in circadian rhythms, leading teens to
stay up late and sleep in
“Owl” vs. “lark” sleep patterns
- Owls prefer to stay awake at night while Larks go to bed early and get up early
,Definition of circadian rhythm
- Biological processes that are on a 24 hour cycle
- Circa: around or about
- Diem: day
Definition of zeitgeber. W
hat are some examples?
- External stimulus that serves to entrain internal biological rhythms
What are some modern negative influences on sleep?
- Working night shifts, jobs and school on strict schedule and artificial light
Definition of Seasonal Affective Disorder. W
here region of this U.S. is it most common in? How
is it treated?
- Symptoms of depression associated with shorter days of winter
- Common in northern latitudes and treated with bright light exposure
Definition of melatonin. H
ow does it affect our health?
- Hormone secreted by the pineal gland at night which helps regulate the sleep/wake
cycle
- Changes in melatonin production linked to sleep/mood disorders, cancer and
cardiovascular diseases
What does blue light (like from computers) negatively affect?
- It’s harmful to melatonin production
What type of light is better for preserving melatonin?
- Red light
What brain structure regulates circadian sleep cycles?
- The nucleus in the hypothalamus
What happens if a certain nucleus in the hypothalamus is lesioned?
- You will sleep at random times during the day
Sleep lab measurements
- Participants are hooked up to electrodes to record their EEG
Sleep stages
Awake:
-Alpha activity: occurs when resting quietly, especially with eyes closed
-Beta activity: occurs when a person is active and alert
, Sleep: what does each stage look like?
REM: EEG becomes desynchronized again with beta and theta activity, eyes
darting around rapidly, dreaming occurs
Non-REM
-Stage 1: theta waves, larger slower waves. Transition between sleep and
wakefullness
-Stage 2: theta activity. Interspeed sleep spindles and K complexes
-Stage 3: 20-50% large amplitude delta activity
-Stage 4: more than 50% delta activity
In what stage do the following occur:
*Sleep spindles: short burst of brain activity during stage 2
* K complexes: spontaneously occur 1x per minute during stage 2 but is also
triggered by noises
*theta waves: stages 1 and 2
*delta waves: stages 3 and 4
*slow wave sleep: stages 3 and 4. Most difficult to wake up from
What type of sleep is also called “paradoxical sleep”?
- REM sleep because brain waves resemble walking
At what point in development do people need the most sleep?
- Newborns need the most sleep
Definition of REM rebound
- Period when we catch up on REM sleep
How is REM sleep related to mood?
- People with depression spend more time in REM sleep than normal
What sleep stage do behaviors such as bedwetting, sleepwalking, and night terrors happen in?
What do these behaviors look like?
- During slow wave sleep (stages 3 and 4, not REM sleep)
Which sleep stage does sleep talking happen in?
- Phases 1 and 2
What does sleep look like throughout the course of the night? (starts at 37:08 in week 8 lecture)
- Non rem sleep becomes less common, REM sleep becomes more common, easier to
wake people up in second half of a nights sleep, if we wake up on our own it’s often
during REM sleep (dreams)
Definition of consciousness
- A state of awareness
- Awake vs asleep
- Content of thought
- Self awareness
Benefits of having consciousness
- Behavioral flexibility
- Greater drive to survive?
- Navigating a complex social environment
Tests for consciousness/self-awareness
- Rouge test (when can humans usually pass it?)
- Humans who are over 18 months, chimps, orangutans, asian elephants, etc
How the following brain areas are related to consciousness:
- Thalamus: relay station of the brain
- Reticular formation: reticular formation (in the brain stem). Regulates sleep and wake
cycles
Benefits of being unconscious/sleeping. What are possible reasons we evolved to sleep?
- We sleep to let the body rest and restore itself
- Sleep helps with learning and development
Examples of how altered sleep or jet lag can affect our behavior/cognitive abilities
- It disrupts the daily sleep cycles. Travelling west is easier and the more time zones you
cross increases the likelihood of jet lag
How can bright light exposure help jet lag?
- Morning: bright light advances circadian rhythm, allowing sleep to occur earlier
- Night: bright light delays circadian rhythm, allowing sleep to occur later
How do sleep requirements change with age?
- You need more sleep when you’re younger
Definition of phase delay. When does it typically occur?
- Hormones released at puberty cause phase delay in circadian rhythms, leading teens to
stay up late and sleep in
“Owl” vs. “lark” sleep patterns
- Owls prefer to stay awake at night while Larks go to bed early and get up early
,Definition of circadian rhythm
- Biological processes that are on a 24 hour cycle
- Circa: around or about
- Diem: day
Definition of zeitgeber. W
hat are some examples?
- External stimulus that serves to entrain internal biological rhythms
What are some modern negative influences on sleep?
- Working night shifts, jobs and school on strict schedule and artificial light
Definition of Seasonal Affective Disorder. W
here region of this U.S. is it most common in? How
is it treated?
- Symptoms of depression associated with shorter days of winter
- Common in northern latitudes and treated with bright light exposure
Definition of melatonin. H
ow does it affect our health?
- Hormone secreted by the pineal gland at night which helps regulate the sleep/wake
cycle
- Changes in melatonin production linked to sleep/mood disorders, cancer and
cardiovascular diseases
What does blue light (like from computers) negatively affect?
- It’s harmful to melatonin production
What type of light is better for preserving melatonin?
- Red light
What brain structure regulates circadian sleep cycles?
- The nucleus in the hypothalamus
What happens if a certain nucleus in the hypothalamus is lesioned?
- You will sleep at random times during the day
Sleep lab measurements
- Participants are hooked up to electrodes to record their EEG
Sleep stages
Awake:
-Alpha activity: occurs when resting quietly, especially with eyes closed
-Beta activity: occurs when a person is active and alert
, Sleep: what does each stage look like?
REM: EEG becomes desynchronized again with beta and theta activity, eyes
darting around rapidly, dreaming occurs
Non-REM
-Stage 1: theta waves, larger slower waves. Transition between sleep and
wakefullness
-Stage 2: theta activity. Interspeed sleep spindles and K complexes
-Stage 3: 20-50% large amplitude delta activity
-Stage 4: more than 50% delta activity
In what stage do the following occur:
*Sleep spindles: short burst of brain activity during stage 2
* K complexes: spontaneously occur 1x per minute during stage 2 but is also
triggered by noises
*theta waves: stages 1 and 2
*delta waves: stages 3 and 4
*slow wave sleep: stages 3 and 4. Most difficult to wake up from
What type of sleep is also called “paradoxical sleep”?
- REM sleep because brain waves resemble walking
At what point in development do people need the most sleep?
- Newborns need the most sleep
Definition of REM rebound
- Period when we catch up on REM sleep
How is REM sleep related to mood?
- People with depression spend more time in REM sleep than normal
What sleep stage do behaviors such as bedwetting, sleepwalking, and night terrors happen in?
What do these behaviors look like?
- During slow wave sleep (stages 3 and 4, not REM sleep)
Which sleep stage does sleep talking happen in?
- Phases 1 and 2
What does sleep look like throughout the course of the night? (starts at 37:08 in week 8 lecture)
- Non rem sleep becomes less common, REM sleep becomes more common, easier to
wake people up in second half of a nights sleep, if we wake up on our own it’s often
during REM sleep (dreams)
