Transcript Document

Chapter 1: Introduction
to Cognitive Psychology
Joel Cooper
University of Utah
Bias
• To influence in a particular, typically unfair
direction; prejudice.
• Everyone is biased.
• This class deals with fundamental questions
such as
– Learning, memory, attention, knowledge, language,
creativity, decision making and intelligence.
• This is a science class and offers an explanation
for these phenomenon from that perspective.
Accretion of Knowledge
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100,000 years of modern man
6,000 years with the wheel
110 years with the car
55 years with the jet
Why wasn’t the wheel invented
earlier?
• Why the recent explosion in
technology?
A graphical rendering of knowledge
accumulation
Dissemination
of Knowledge
in the World
Distance
Arbitrary amount of
background knowledge
needed for the invention of
the wheel
Time
What speeds the buildup of
knowledge?
• Those things which increase the amount
of information that can be stored over time
and shared across distance.
– Knowledge that cannot be stored is lost.
– Knowledge that cannot be shared is not
augmentive.
Knowledge Growth
• Keys to knowledge growth
– Storage
– Transmission
• The knowledge feedback loop creates
exponential growth in the knowledge base
from which knowledge is created. Each
new device speeds the process of growth
by increasing the amount of information
that can be shared across distance and
time.
Knowledge
• Builds based on what’s available
• There is no simple or obvious
advancement
• Little available knowledge in societies:
– Without writing
– With little inter-group contact
– Groups with low population density
• Role of the elderly was very different then
Recent contributors to the buildup
of knowledge
• Agriculture
– Trade
– Class divisions
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Horses
Writing
Medical technology
Automobiles
Phones
Airplanes
Internet
Cultural transmitters of knowledge
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Songs
Dance
Oral traditions
Mythology
Religion
Science
Conflicts among cultural
transmitters
• Song, dance and oral traditions change in
the telling and may share conflicting
information
• Mythologies can conflict
• Religions can conflict
• Science can conflicts
• They can all conflict with each other but
they are not all have the same explanatory
power.
How does Science differ from
other structures that disseminate
and advance knowledge?
• Testable
• Replicable
• Falsifiable
Scientific knowledge is never set, never certain and
always growing.
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Objective – Treating or dealing with facts
without distortion by personal feelings or
prejudices
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Subjective - Proceeding from or taking
place in a person's mind rather than the
external world
- Particular to a given person
Science: The only objective method to the
advancement of knowledge.
Science and the study of “mind”
• Other cultural traditions offer stable information on the
mind
• Science offers an uncertain account
• Other explanations may feel “warm” and intuitively
appealing
• Scientific explanation may at first feel “cold”
– Oxytocin the “love drug”
• Scientific explanation for the mind is rich, elaborate and
based on solid objective principles.
• Scientific explanation for the “mind” is dynamic and
continues to grow (which I find exciting).
Dialectic Progression of Ideas:
Hegel
Thesis
flaws/alt idea
Antithesis
Synthesis:
best of both
New Thesis
flaws/alt idea
Philosophical Roots
Rationalist
Logic & reasoning
is key
Empiricist
Experience & observation is
key
Cognitive Psychology Is…
• The study of how people perceive, learn,
remember, and think about information.
Memory
Problem
Solving
Decision
Making
Attention
Intelligence
Language
Perception
Cognitive Methods
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Experiments
Psychobiological studies
Self report
Case studies
Naturalistic Observation
Computer Simulations
In an Experiment…
• Random sample of participants
• Manipulate the Independent Variable
– Create experimental group
– Create control group
– Randomly assign participants
• Measure the Dependent Variable
– Same for all groups
• Control all other variables
– Prevent confounds
Typical Independent Variables
• Manipulate stimulus materials
– Compare words to non-words
– Compare color diagrams to black and white
– Compare Yes questions to No questions
• Control how participants process
materials
– Use imagery to study versus repetition
– Vary speed of presentation of materials
Typical Dependent Variables
• Reaction Time (milliseconds)
– Mental events take time
• Accuracy/Error analysis
– How well the participant does on a task
Psychobiological Studies
• Postmortem studies
– Examine the cortex of dyslexics after death
• Brain damaged individuals and their deficits
– Study amnesiacs with hippocampus damage
• Monitor a participant doing a cognitive task
– Measure brain activity while a participant is
reciting a poem
Self Report Studies
• Verbal Protocol
– Participants describe their conscious thoughts
while solving a story problem
• Diary Study
– Participants keep track of memory failures
• Naturalistic Observation
– Monitor decision making of pilots during flights
Case Studies
• Intensive studies of individuals
– May examine archival records, interviews,
direct observation, or participant-observations
• Creativity of successful individuals
• The deficits of a neglected child
Computers in Research
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Analogy for human Cognition
– The sequence of symbol
manipulation that underlies
thinking
– The goal: discovery of the
programs in humans’ memory
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Computer simulations of
Artificial Intelligence
– Recreate human processes
using computers
Pop Quiz
25 Questions
 Studies have shown that eyewitness testimony is valid and
accurate, especially with highly stressful (i.e., memorable)
events.
 False -- Eyewitness testimony is notoriously unreliable,
particularly when the observer is in a highly aroused state.

As of January 7, 2006 172 wrongly convicted prisoners
have been released from death row because they were
factually innocent of the crime. Most were committed on the
basis of eye witness testimony.
25 Questions
 We use only about 10% of our brain.
 False -- We use all or our brain all the time. Even small brain
lesions can result in significant cognitive impairment. The
distributed neuronal cell loss with age amounts to up to 25% of
the brain volume and accounts for many effects of cognitive
aging.
25 Questions
 Someone who learns something when they are drunk will
subsequently remember it better when they are drunk than
when they are sober.
 True -- State dependent learning demonstrates the importance
of the “cognitive environment” in the formation and retrieval of
episodic memories. When there is a match between context,
retrieval is good.
25 Questions
 Studies of divided attention have demonstrated that driving
while using a cell phone is not impaired.
 False -- Studies show that using a cell phone significantly
interferes with driving. In fact, several studies show that you
are more impaired when driving and talking on a cell phone
than when you are driving drunk.
25 Questions
 Recent evidence supports some of the claims of Extra
Sensory Perception (ESP) advocates.
 False -- In controlled “double-blinded” studies, no systematic
evidence has been obtained for ESP.
25 Questions
 Memory aids do not really improve our memory.
 False -- Mnemonic techniques work. They organize the
information, make the material less susceptible to forgetting
or interference, and provide a useful retrieval structure.
25 Questions
 Backwards messages hidden in music influence our
behavior.
 eslaF -- There is no evidence that this information is
processed, let alone influences our behavior.
25 Questions
 Speed reading techniques can dramatically improve reading
speed without sacrificing comprehension.
 False -- Human performance is governed by the speedaccuracy tradeoff -- Going faster results in lower accuracy.
However, good old fashioned practice can improve the
efficiency of reading.
25 Questions
 Freud's "free association" technique tells us something about
the organization of memory.
 True -- This is similar to the semantic priming studies with
spreading activation. Individual differences can reflect
enduring predispositions (or partial patterns of activation) that
bias the semantic network in one way or another.
25 Questions
 Information can be stored in long-term memory even if you
never attended to it.
 False -- Attention is necessary for the creation of long-term
(and short-term) memories. Information that falls outside of
attention is lost.
25 Questions
 Advertising using subliminal perception is very effective.
 False -- Effects of subliminal perception are, at best, minimal.
There is little evidence that stimuli presented below the
observer’s threshold influence motives, attitudes, beliefs, or
choices.
25 Questions
 We should try to avoid using heuristics (rules of thumb)
during decision making.
 False -- Heuristics help speed the decision making process
and unburden working memory. However, these simplifying
rules or short-cuts do create biases in decision making.
25 Questions
 There is no basis for the claim that eating carrots will help
your night vision
 False -- The rods use the photopigment rhodopsin (which is
made up of vitamin A, also found in carrots). People with a
vitamin A deficiency can have poor night vision which can be
corrected by supplemental vitamins.
25 Questions
 Infant’s ability to discriminate between the phonemes of
language is actually better than that of adults.
 True -- As language develops, infants loose the ability to
discriminate or produce phonemes that are not in their
language.
25 Questions
There is no limit on how much information can
be stored in long-term memory.
True -- No one has ever filled up long-term
memory. There may be limits on what
information is initially stored (attentional
limitations), but once stored, the memories
are permanent (although they may not be
accessible).
25 Questions
 People who are color blind are missing one or more types of
cones in the retina
 True -- Trichromatic theory suggests that normal color vision
depends on three cone types with different colors made up
by the ratio of activation of these receptors. However, some
forms of color vision can also be due to damage to cortical
areas.
25 Questions
 The arrangement of displays and controls in cars, airplanes,
etc. is arbitrary because we can learn to use any
configuration with practice.
 False -- There are some configurations that result in
interference that simply can’t be practiced away. It is up to
Human Factors professionals to root out these bad design
principles.
25 Questions
 People are always biased.
 True -- Our expectations and memories color the way that we
perceive and remember the world. This accounts for many of
the individual differences between people.
25 Questions
 Practice always improves performance.
 False -- Learning capitalizes on the statistical regularities of
the environment. Most of the time there are consistencies in
the environment that facilitate learning, but in some cases
there are irregularities or inconsistencies that impede
learning.
25 Questions
 Our expectations influence our perceptions and memories.
 True -- Expectations and other “top-down” processes play a
major role in what we perceive and remember. Often,
differences in what two observers see or remember are due
to the effects of top down processing.
25 Questions
 The difference between $500 and $1000 is psychologically
greater than the difference between $10,500 and $11,000.
 True -- The mental representation of magnitude is
compressed at the high end of the scale. 500 vs. 1000 is a
greater psychological difference than 10500 vs. 11000
25 Questions
 If someone is blind in one eye, they will have no depth
perception.
 False -- There are pictorial cues (e.g., size, interposition, etc)
and movement cues that provide depth information. The use
of both eyes provides binocular cues -- random dot
stereograms make use of binocular visual information.
25 Questions
 With enough practice it is possible to do two things at the
same time as well as doing each thing by itself.
 True -- Under very specific task combinations, people can do
two things (playing piano and reading a novel) as well as
either in isolation. This is called “Perfect Timesharing”.
25 Questions
 During the movement of the eyes while reading, the
processing of visual information is temporarily suppressed.
 True -- This is called saccadic suppression. Not only is the
processing of visual information suppressed, but higher level
cognitive thoughts also appear to be put on hold.
25 Questions
 It is possible to have a permanent memory that influences
your behavior even though you are not consciously aware of
that memory.
 True -- The distinction between implicit and explicit memory
suggests that implicit memory is very important to out
everyday behavior, even though we may be unaware of these
memories.