Lecture: Dreaming

Question 1

When does dreaming occur?

Answer 1

Dreaming can occur in REM and non REM (NREM) states

Question 2

what percentage of our sleep is NREM?

Answer 2

75%

Question 3

What are NREM dreams like?

Answer 3

tend to be short, dull and undreamlike (e.g., walking, eating, not story like)

Question 4

What is REM sleep characterized by?

Answer 4

Rem sleep is characterized by rapid eye movement, muscle atonia (temporary paralysis sorta) and often dreaming

Question 5

What disorders are associated with sleep?

Answer 5

• Muscle atonia is caused by part of the brain called pons
• If you disable the pons in cats, they engage in stalking behaviour during REM.
• REM sleep disorder (paralysis that typically occurs is absent, people act out their dreams)
• Sleepwalking (somnambulism)NREM sleep

Question 6

What do people who have no dream imagery have?

Answer 6

People who have no dream imagery (visual anoneria) tend to also have a waking deficit in imaging memories (visual irreminisence)

Question 7

What is our dream recall capability like?

Answer 7

• We typically forget dreams
• Correlates with visuospatial skill and individual differences in working memory
• Animals and infants cannot report dreams
• Commonly people assert that there was much more to their dream than they can report

Question 8

What are the worst to best ways to record dreams?

Answer 8

• Ask people what their dreams tend to be like
• Ask people to keep a dream diary (a little more systematic)
• Ask people every morning to report their dreams
• Wake people up during sleep at many points during the night and get reports (scientifically best way)

Question 9

What are dreams like?

Answer 9

• Scene shifts are common
• Tend to be narrative
• Tend to be experienced “first person”
• Dream emotion tends to match content
• Dreams can be bizarre but not often this way

Question 10

What else are dreams like?

Answer 10

• They are always animated.
• Dreams are rarely bizarre, but when they are we often do not really notice it until we are awake
• Selection bias: bizarre dreams are easier to remember and are more often talked about

Question 11

What are dreams not like?

Answer 11

• Films, visual images, recent social situations, and pre sleep behaviour are rarely incorporated into dreams
• Recent episodic memories, even salient ones are rarely incorporated

Question 12

What kind of inferences can dreams get from the world?

Answer 12

• Dreaming you need to urinate

- Dreaming of teeth falling out (which 70% of people do during sleep) caused by dental irritation

Question 13

How can you affect your dreams?

Answer 13

• Pre-sleep attention to a specific concern

- This is called “dream incubation”

Question 14

What is threat stimulation theory (TST)?

Answer 14

• By philosopher Antti Revonsuo

- A major function of dreaming is to practice dealing with threats that were common in our ancestral environment

Question 15

What is the support for TST?

Answer 15

• Animal dreams are highest in kids and decreases with age
• Negative emotions appear twice as often as positive ones in dreams
• The only kind of recurring dream with any frequency is being threatened by animals, monsters, people or natural disasters and the response was watching, Running or hiding.
• Proposed to be for the same reason that children play pretend, to practice for real world situations. It is evolutionary
• Animals dream decrease with age, suggesting its evolutionary. As they learn and get enculturated they stop having these preparation dreams

Question 16

What is some more support for TST?

Answer 16

-Westerners dream of things we rarely
experience
-Ancestral threats are overrepresented
-People react appropriately to dream
threats 94% of the time

Question 17

Where else are ancient survival behaviours over represented?

Answer 17

• Ancient survival behaviours are also overrepresented in play and in phobias
• Animals play appropriately for what they need to learn to do

Question 18

What is the dreaming brain like?

Answer 18

• The brainstem is very active, sending information forward
• The DLPFC (involved with executive function) is deactivated
• perhaps explaining our reduced reasoning ability during dreams
• Not noticing what’s weird
• Uninhibited behaviour
• But also our difficulty in remembering dreams

Question 19

What is the AIM model of conscious state?

Answer 19

• Activation: Basic level of brain activation
• Information flow: Sensory input vs. internal, fictive input
• Model of information processing: Aminergic, cholinergic neuromodulation
• Activation-synthesis hypothesis: Dreams are the cortex trying to make sense of chaotic inputs from the brainstem

Question 20

What support is there for the activation synthesis hypothesis?

Answer 20

• Dream emotion seems to shape dreams, not the other way around (e.g., an anxiety dream will often shift from one anxiety producing to the other)
• Dream recall cessation is almost always caused by forebrain lesions

Question 21

What is lucid dreaming?

Answer 21

• When you know you’re dreaming and can control your actions, and sometimes other dream content.
• You can only control your eyes in the real world
• Could be a reactivation of the DLPFC, which allows you to see dream content for what it is, and control yourself.
• Training: dream diaries, reality checks, tech

Question 22

What is sleep paralysis characterized by?

Answer 22

• You feel awake
• You might feel chest pressure
• You can’t move
• It’s a carryover of muscle atonia from sleep to waking
• You have hallucinations, often of the presence of a malevolent character
• You feel abject terror