Sleeping

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Dreaming: What’s Going on?
• Dream behavior
• Theories of Dreaming
• Conclusions
– What can we learn from our dreams?
• Are they meaningful? True / predictive?
• Basic Methodology (if we have time…)
Some Questions:
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Are Dreams meaningful--what do they mean?
Are the predictive or “true”?
How do they differ from other states?
What is their function do they even have one?
Are they brain functions or mind functions?
Dream behavior & description
• Within sleep
• Amount
• Brainwave activity & bodily quietude
– the paradox
• REM
Dreams & REM sleep
• REM amount & periodicity
• Brainstem cholinergic & adrenergic
promoting & inhibiting areas
• A regular activity rooted in the brain
Outline
• Characteristics and Descriptions
• Theories of Dreaming
• Conclusions
– What can we learn from our dreams?
• Are they meaningful? True / predictive?
• Basic Methodology (if we have time…)
Theories of Dreaming
• Dreams as meaningful events:
• Freud (& Jung)
(--Poetzel effect)
--Aserinsky, Dement & Kleitman
implications
• Hall/Cartright
• Dreams as random activity (Hobson +)
• Synthesis (perhaps)
Psychoanalytic Theory
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Mental conflict
Unconscious motivations
Two forces: impulses & defenses (repression)
Dreams as a release
Dreamwork and its results
– Latent dream
– Manifest dream
– Remembered dream
Dreamwork and forgetting as protective mechanisms
Poetzel Effect,
Freud & Neuroimaging
• Michael Anderson- Validates Repression: Forebrain active in
inhibiting hippocampus on repressed items
• Allen Braun: Limbic system-emotion active during REM)
• Prefrontal cortex (working mem. Att’n, logic & self-monitoring)
inactive during REM
• Above consistent with dream bizarreness & emotional
disinhibition/wish fulfillment
• Visual cortex inactive but higher visual areas active so we see
w.o. visual input- one of the amazing things about dreaming!
Freud & Neuroimaging (Mark Solms)
Injured Pons vs. injured Forebrain
-Pons-disrupts REM but dreaming goes on.
-Forebrain-lose dreaming but REM goes on.
-Also, some dreaming outside of REM
Role of Motivation (in addition to emotional areas)
-Prefrontal leukotomy (white matter in ventro-medial
forebrain area) decreases dopamine release. It’s a
motivational area “seeking” behavior.
-Hartmann: administering dopamine supercharges
dreaming! Freudian tie between motiv. & dreaming.
Variations on Psychoanalytic
Explanation + Challenges
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Aserinsky, Dement & Kleitman: REM & implications
Hall and Cartwright: Dream Series
Challenging Views
Dreams as random activity (Hobson +)
Synthesis (perhaps)
Other Neuroscience Views
• Crick: Purge extraneous connections
• Evans: Sorting function on day’s events
• Winson: Sorting for survival: Neurons
reactivated during dreams
• Wilson: Rat Dream article- maze
learning during dreams
• Hobson: random activity & activationsynthesis hypothesis
Hobson: Dream Transformations
• From:
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inanimate animate character
To:
inanimate
Animate
Character
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7
14
Dream Characteristics
Lack of active volition
Absence of ongoing reflective judgment
Limited to phenomena of the immediate present
Diffuse cognitive slippage--dreamlike confusiontransformations of perception, thought, memory, emotion,
relationships, etc.
Gaps in experience: 20%
Confusion of thought & irrational intuitions: 41%
Problems in sustained attention: 5%
Memory deficiencies within the dream: 15%
Overall, even 51% of "clearest dreams" had clouding of cs.
--Usually not radical (scz, psychedelic) but rather more like that of waking life
Can even have hallucinations or psychedelic exper. in
dreams (as in waking life!) ex. flying 4%, bizarre figures,4%,
changed identity 3%, LSD-like transformations of
vision 13%. Mostly visual 47%. Somatic 10%, audit. 14%.
Conclusions
• Can we obtain meaningful insights
about ourselves through our dreams?
• What can we learn from our dreams?
• Are they meaningful? true /
predictive/useful?
• Dream problem-solving (Lowie, Kekule)!
Outline
• Characteristics and Descriptions
• Theories of Dreaming
• Conclusions
– What can we learn from our dreams?
• Are they meaningful? True / predictive?
• Basic Methodology
Basic Methodology
• Experimentation
– Independent vs. Dependent variables
– Observational vs. Experimental studies
• Causation vs. Correlation
• Experimental “control”
Making Observations
• Scientific observations often begin with a
question or hypothesis.
• The hypothesis must be testable.
• This calls for an operational definition of key
terms to specify the study’s dependent
variable.
• Data must also be systematically collected.
• Researchers ignore anecdotal evidence.
Defining the Sample
• Based on observations of a sample,
psychologists want to draw conclusions
about a broad population.
• Random sampling
• All members of the population have an
equal chance of being picked to
participate.
• Researchers also use other procedures,
including stratified sampling and case
The Power of Experiments
• The two groups must be matched at the
outset of the experiment.
• To ensure matching groups,
researchers use:
• random assignment (ex. Clinical trials)
• within-subject comparison.
• taking precautions to address problems created
by the sequence of conditions
The Control Condition
Assessing External Validity
• Researchers want their study to mirror
circumstances of the broader world.
• external validity
• External validity depends on many
factors.
• The study should not change behaviors the
researchers hope to understand.
Assessing External Validity
• One concern here involves the study’s
possible demand characteristics:
• cues that can signal to participants how
they’re supposed to behave
• One way of avoiding this problem is to
use a double-blind design.
Measurement
• The Description of Data
– Central tendency
• Mean, median, mode
– Variability
• Variance
• Standard deviation
– Correlation & significance level
Measurement
T
H
HT
TT
T = tails
H = heads
TH
HH
Correlation Coefficients (0 – 1)
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