Ch 8 Power Point

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Chapter 8: Language and
Thought
The Cognitive Revolution
• 19th Century focus on the mind
– Introspection
• Behaviorist focus on overt responses
– arguments regarding incomplete picture of human
functioning
• Empirical study of cognition – 1956 conference
– Simon and Newell – first computer program
simulating human problem solving
– Chomsky – new model that changed the study of
language
– Miller – famous paper arguing for the 7 plus or
minus two capacity of STM
Language: Turning Thoughts into Words
• Cognitive science has since grown into a
robust, interdisciplinary field focusing on
language, problem solving, decision-making,
and reasoning
• Language is defined as consisting of symbols
that convey meaning, plus rules for
combining those symbols, that can be used to
generate an infinite variety of messages
Language: Turning Thoughts into Words
• Properties of Language
– Symbolic: people use spoken sounds and
written words to represent objects, actions,
events, and ideas
– Semantic: meaningful
– Generative: a limited number of symbols
can be combined in an infinite number of
ways to generate novel messages
– Structured: there are rules that govern
arrangement of words into phrases and
sentences
The Hierarchical Structure of Language
• Basic sounds are combined into units with meaning,
which are combined into words, which are combined
into phrases, which are combined into sentences.
• Phonemes = smallest speech units
– 100 possible, English – about 40
• Morphemes = smallest unit of meaning
– 50,000 in English, root words, prefixes, suffixes
• Semantics = meaning of words and word
combinations
– Objects and actions to which words refer
• Syntax = a system of rules for arranging words into
sentences
– Different rules for different languages
– (Verb or subject first in a sentence?)
Language Development: Milestones
• Initial vocalizations similar across languages
– Crying, cooing, babbling (of all phonemes.)
• 6 months – babbling sounds begin to resemble
surrounding language
• 1 year – first word
– similar cross-culturally – usually dada, mama,
papa, etc
– While few words are spoken (expressive
language) at this stage, research indicates that
very young children may actually understand
(receptive language) more language than they can
produce.
Table 8.2 Overview of Typical Language Development
Language Development:
Milestones Continued
• 18-24 months – vocabulary spurt, slow
acquisition of new words suddenly spurts
– fast mapping: process by which children
map a word onto an underlying concept
after only one exposure
– Toddlers often make errors in using new
words. Overextensions occur when a child
incorrectly uses a word to describe a wider
set of objects or actions than it is meant
to…using the word ball for anything round
Language Development:
Milestones Continued
• End of second year – children begin combining
words to produce meaningful sentences
– These sentences are characterized as telegraphic,
because they resemble telegrams, consisting
mainly of content words, with articles,
prepositions, and other less critical words
omitted…ex., “Give doll,"
– Researchers study the language of young children
by calculating the MLU (mean length of utterance),
the average length of their spoken statements
(measured in morphemes).
Language Development:
Milestones Continued
• End of third year – complex ideas, plural,
past tense
– Overregularization: generalizing
grammatical rules incorrectly to irregular
cases where they do not apply…”he goed
home,” for example.
• Years 4-5: Largest strides in developing
language
Bilingualism:
Learning More Than One Language
• Research findings:
– Smaller vocabularies in one language, combined
vocabularies average
– Higher scores for middle-class bilingual subjects
on cognitive flexibility, analytical reasoning,
selective attention, and metalinguistic awareness
– Slight disadvantage in terms of language
processing speed
– 2nd languages more easily acquired early in life
– Greater acculturation facilitates acquisition
• Acculturation is the degree to which a person is
socially and psychologically integrated into a
new culture
Figure 8.4 Age and second language learning
Can Animals Develop Language?
• Researchers have attempted to teach
language to a variety of animals, but the most
success has been shown with chimpanzees.
• Dolphins, sea lions, parrots, chimpanzees
– One of the biggest problems in teaching
human language to non-human animals is
that the vocal apparatus is not the same
– American Sign Language
Can Animals Develop Language?
• Allen and Beatrice Gardner (1969)
– Chimpanzee - Washoe
– 160 word vocabulary, combining them into
simple sentences, but showing little
evidence of mastering the rules of
language
Can Animals Develop Language?
• Sue Savage-Rumbaugh
– Bonobo chimpanzee – Kanzi
• geometric symbols that represent words on a
computer-monitored keyboard
• the star pupil, has taught his younger sister
much that he has learned about this system.
Kanzi has acquired hundreds of words and has
used them in thousands of combinations, many
apparently spontaneous and rule governed
– his receptive language appears much more
developed, as he was able to carry out 72% of
660 spoken requests such as “Pour the Coke in
the lemonade."
Theories of Language Acquisition
• Behaviorist
– Skinner
• learning of specific verbal responses
• children acquire language through
conditioning and imitation
• Nativist
– Chomsky
• assert that humans have an innate
capacity to learn the rules of language
• Language Acquisition Device (LAD):
facilitates language development.
Theories of Language Acquisition
• Interactionist: hold that biology and
experience both make important contributions
– Cognitive: asserts that language
development is an important aspect of
more general cognitive development,
depending, like all development, on both
maturation and experience.
– Social communication: interpersonal
communication has functional value and
emphasizes the social context in which
language evolves.
Figure 8.5 Interactionist theories of language acquisition
Theories of Language Acquisition
• Emergentist theories:
– neural circuits supporting language are not
prewired,
– rather emerge gradually in response to
learning experiences via incremental
changes in connectionist networks
Problem Solving: Types of Problems
• Greeno (1978) – three basic classes
• Problems of inducing structure
– Series completion and analogy problems
– where people are required to discover relations
among numbers, words, symbols, or ideas
• Problems of arrangement
– String problem and Anagrams
– where people arrange the parts of a problem in a
way that satisfies some criterion. These types of
problems are often solved by insight, a sudden
discovery of the correct solution following incorrect
attempts based primarily on trial and error
Problem Solving: Types of Problems
• Problems of transformation
– involve carrying out a sequence of
transformations in order to reach a specific
goal
– Hobbits and orcs problem
– Water jar problem
Figure 8.6 Six standard problems used in studies of problem solving
Effective Problem Solving
• Well defined vs. ill defined problems
– Problems vary in the degree to which they
are well defined, where the initial state, the
goal state, and the constraints are clearly
specified;
– most problems in the real world are illdefined, that is, one or more elements
among the initial state, the goal state, and
the constraints are incompletely or
unclearly specified.
Effective Problem Solving
• Barriers to effective problem solving:
– getting bogged down in Irrelevant
Information
– Functional Fixedness: the tendency to
perceive an item only in terms of its most
common use
– Mental Set: people persist in using
problem-solving strategies that have
worked in the past
– Unnecessary Constraints: assuming
unnecessary constraints on the problem
Figure 8.12 The tower of Hanoi problem
Approaches to Problem Solving
• Algorithms
– An algorithm is a methodical, step-by-step
procedure for trying all possible
alternatives in searching for a solution to a
problem
– Guaranteed solution
Approaches to Problem Solving
• Heuristics
– Shortcuts, guiding principles or “rules of thumb”
used in solving problems
– No guaranteed solution
• Forming subgoals: allows one to solve part of
the problem
• Working backward: works well for a problem
that has a specified end point
• Searching for analogies: involves using a
solution to a previous problem to solve a
current one
• Changing the representation of a problem:
Figure 8.16 Representing the bird and train problem
Culture, Cognitive Style,
and Problem Solving
• Some cultures foster field dependence, a reliance on
external frames of reference.
• Others foster field independence, reliance on internal
frames of reference. People who are field
independent tend to analyze and restructure
problems more than those who are field dependent.
– Western cultures inspire field independence
– Cultural influence based in ecological demands:
the necessary survival skills in a culture
Culture, Cognitive Style,
and Problem Solving
• Holistic vs. analytic cognitive styles
– Nisbett and colleagues (2001) argue that people
from East Asian cultures display a holistic
cognitive style – focusing on context and
relationships among elements in a field (wholes).
– People from Western cultures show an analytic
cognitive style – focusing on objects and their
properties rather than context (parts).
• Nisbett argues that field-dependence/
independence is just one facet of a broader
preference for holistic vs. analytic thinking
• The caravan of a wealthy desert dweller is
approaching an oasis after a long, hot day. He says
to two of his lieutenant, To the one of you whose
horse gets to the oasis last, I’ll give this camel laden
with gold. Immediately they both stop. By the time the
rear guard of the caravan reaches the two
lieutenants, they have dismounted their horses and
each is waiting on the sand for the other to become
so hot and thirsty that getting to the oasis cannot be
resisted. Finally, they tell the guard their dilemma and
ask for help. He says two words to them, whereupon
the lieutenants jump onto the horses and race toward
the oasis. What did the guard tell them?
Switch Horses!
Decision Making:
Evaluating Alternatives and Making Choices
• Simon (1957) – theory of bounded rationality
– holds that human decision making strategies are
simplistic and often yield irrational results
• Making Choices
– Additive strategies: used to make choices by
rating the attributes of each alternative and
selecting the alternative with most desirable
attributes
– Elimination by aspects: making choices by
gradually eliminating unattractive alternatives
Decision Making:
Evaluating Alternatives and Making Choices
• Making Choices (cont.)
• Research shows that people tend to use
additive strategies when decisions involve
relatively few options that need to be evaluated
on only a few attributes
• They shift to elimination by aspects when more
options and factors are added to a decision
making task
• Research shows that people will often pursue
useless information that will not alter their
decisions when making choices
Decision Making:
Evaluating Alternatives and Making Choices
– Risky decision making: making choices
under conditions of uncertainty
• Expected value: involves what you stand
to gain
• Subjective utility: what an outcome is
personally worth to an
individual…insurance and sense of
security
• Subjective probability: involves personal
estimates of probabilities…often quite
inaccurate
Table 8.3 Application of the additive model to choosing an apartment
Heuristics in Judging Probabilities
• The availability heuristic: involves basing the
estimated probability of an event on the ease with
which relevant instances come to mind…
– estimate divorce rate by recalling number of
divorces among your friends’ parents
• The representativeness heuristic: involves basing the
estimated probability of an event on how similar it is
to the typical prototype of that event
– plays into the tendency to ignore base rates
– guessing that Steve is a librarian because he
looks like a librarian, even though you know that
salespeople greatly outnumber librarians in the
population
Heuristics in Judging Probabilities
• The conjunction fallacy: occurs when people estimate
that the odds of two uncertain events happening
together are greater than the odds of either event
happening alone
– this also appears to be due to the powerful nature
of the representativeness heuristic
• The alternative outcomes effect: occurs when
peoples’ belief about whether an outcome will occur
changes, depending on how alternative outcomes are
distributed
– even though the summed probability of the
alternative outcomes is held constant.
Figure 8.18 The conjunction fallacy
Understanding Pitfalls in Reasoning
About Decisions
• The gambler’s fallacy: the belief that the odds
of a chance event increase if the event hasn’t
occurred recently
• Overestimating the improbable: describes
how people tend to greatly overestimate the
likelihood of dramatic, vivid, but infrequent,
events that receive heavy media coverage
• Confirmation bias: tendency to seek
information that supports one’s decisions and
beliefs, while ignoring disconfirming
information
Understanding Pitfalls in Reasoning
About Decisions
• Belief perseverance: the tendency to hang onto
beliefs in the face of contradictory evidence
• The overconfidence effect: the tendency for people to
put too much faith in their estimates, beliefs, and
decisions, even when they should know better
• Framing: how decision issues are posed or how
choices are structured
– People often allow a decision to be shaped by
context or by the language in which it is
presented.
Evolutionary Analyses: Flaws in Decision
Making and Fast and Frugal Heuristics
•
•
While research shows that human decision
making is replete with bias and error,
evolutionary psychologists argue that this is
due to the laboratory tasks used to measure
it.
They argue that traditional decision research
has imposed an unrealistic standard in that
questions are asked in ways that have
nothing to do with the adaptive problems
that humans have evolved to solve
Evolutionary Analyses: Flaws in Decision
Making and Fast and Frugal Heuristics
• Cosmides and Tooby (1996)
– argue that human decision making emerged to
solve adaptive problems
• such as finding food, shelter, and mates and
dealing with allies and enemies
• many reasoning errors disappear when
problems are presented in ways that resemble
the type of input humans would have
processed in ancient times
– Unrealistic standard of rationality
– Problem solving research based on contrived,
artificial problems
Evolutionary Analyses: Flaws in Decision
Making and Fast and Frugal Heuristics
• Gigerenzer (2000)
– argues that humans do not have the time,
resources, or capacities to gather all
information, consider all alternatives,
calculate all probabilities and risks, and
then make the statistically optimal decision
– Instead, they use the fast and frugal route,
making quick, one-reason decisions which
yield inferences that are often just as
accurate as much more elaborate and
time-consuming strategies
– Less than perfect but adaptive
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