Cognition, Language, and

Intelligence

Cognition

What is Cognition?

• Literally “thinking”

• The brain’s representations of information in the world around us

• The way the mind processes this information

• Sensation → Perception → Cognition

CategoriesCategories: mental groupings of similar objects, events, and people.

“Chair”

    Organize lots of information with a minimum amount of effort

    Allow us to solve problems quickly

Categories

What determines category membership?

Examples    Triangle    Bachelor

But do categories really fit this definition?

Aristotle: Defining features    look for features that every member of the that category possesses    Either is or is not a member of a category

“Chair”What is common to all of them?

Wittgenstein: “Family resemblance”

Eleanor Rosch studied how people actually use categories: Prototype model

Category membership determined in terms of similarity to “prototypical” exemplars

Examples• Chair• Red

Prototype model

Categories are not “all or none”Instead, they have graded structure

Good example Poor example

Prototype model

Categories have “fuzzy” boundaries

Chair? Chair? Chair? Chair? Chair?

Red? Red? Red? Red? Red?

Prototype properties apply to Natural categories:

e.g., Birds, trees, red Artificial categories:

e.g., Chairs, Aircraft, Weapon

What’s the category?

• Human infant

• Photo albums

• Jewelry

• Dog

• Insurance documents

• Data discs

• Tapestries

What’s the category?Human infantPhoto albumsJewelryDogInsurance documentsData discsTapestries

“Things to take from a burning house” (Barsalou, Ad Hoc Categories)

“things to take on a camping trip”“ways to make friends”“possible costumes to wear to a Halloween party”“emergency firewood”

    Categorizations made with respect to a goal    Things can be cross-categorized

Levels of Categorization

Superordinate Basic SubordinateAnimal Fish TroutFurniture Chair Rocking ChairPlant Tree Oak TreeVehicle Train Freight train

Superordinate: Broadest and least specific category. (e.g., animal, furniture)

Basic: More specific, the level of prototypes. A common level of categorization. (e.g., fish, chair)

Subordinate: Most specific type of category, it has the most distinguishing about of information. (e.g., trout, rocking chair)

Bandwidth-Fidelity Tradeoff

Bandwidth• Number of members included• Superordinate categories have the highest bandwidth

Fidelity• Number of properties• Subordinate categories have the highest fidelity

Basic level categories • Represent best solution to Bandwidth-fidelity tradeoff• Generated first in naming tasks• Learned first by children

Language

• Language– our spoken, written, or gestured

words and the way we combine them to communicate meaning

Animal language

Why study language in animals?

• Communication with animals allows us to learn more about other species

• By examining differences across species we can learn about language

Language vs. Communication

Many animals (especially social animals) communicate

Examples• Bees—“dances” specify distance, direction, & quality of food• Vervet monkeys—Different signals for different predators• Parrots

=> animals can communicate. BUT can they use language?

What is language?

Two conditions must be met:

SEMANTICS - ARBITRARY UNITS (WORDS) WHICH HAVE MEANINGS. Hissing cat? Vervet monkey?

SYNTAX - WORDS ARE ORGANIZED TOGETHER ACCORDING TO RULES

Chomsky: it is syntax that is innately human. Animals can learn words (perhaps) but cannot have a grammar.

Experimental Evidence: can animals be taught to use language?

William Furness (1916) – taught orangutan to speak English

3 words: "Cup" "papa" and "th"

Hayes's (1951): raised a chimp-Vicki-as a human child • tried to teach her English

4 words: "mama" "papa" "cup" & "up"• perhaps chimps do not have coordination and control required to produce spoken language.

Gardners (1969) raised chimp—Washoe—as a human child• Tried to teach A.S.L. (has discrete units and a grammar)• Washoe lived in a trailer behind house for 5 years• Had human companions during all her waking hours

Washoe• Not specifically rewarded for performing a sign• After 4 years had developed 132 A.S.L. signs• apes can meet 1st criterion for a language - use arbitrary symbols as referents for objects (semantics)BUT could apes do syntax? (organize words together according to grammatical rules)• Not clear whether Washoe could do this

• Washoe prompted investigators to look at syntactic competence • Premack trained female chimp, Sarah, to use plastic chips to communicate. • E.g., Blue triangle = apple• Was required to give signs in correct order• Rumbaughs trained several chimps to use “lexigrams” to communicate with each humans & with each other

=> But evidence controversialUsed caged chimpsRewarded animals

Nim Chimpsky• 125 ASL words• Made many 2-word combinations• But did not move on to more complex sentences• 3-word sentences had no more info than 2-word sentences• Most utterances prompted by experimenter• Unlike human infants• Chimps merely repeating what E signed• Chimps prodded by experimenters

Rumbaughs • Examined Bonobos (Kanzi)• Learned early in life• Comprehension of 2.5 year old• Well controlled studies

The experimenter prepares to test Kanzi by placing headphones on his head.

Kanzi listens for spoken English, which comes from another room.

Kanzi generally displays a very intent expression at the moment he recognizes the word.

The experimenter prepares to open a "test booklet" which hold 3 items, one of which corresponds to the word that only Kanzi can hear.

Kanzi gestures with his left hand in a upward motion to signal that he is ready for the test booklet to be shown to him.

Kanzi looks over the photos in the test booklet

Kanzi selects a photograph to indicate which English word he heard through the headphones.

The experimenter congratulates Kanzi on his correct choice.

Human Language

• Language related to our thought processes• Behaviorists: thought = language

But• People with vocal cords paralyzed can think• So can children and nonhuman adults • So can brain-damaged adults• Today, relation between thought & language more complex

=>Language facilitates thought• Some people try to get us to think about differently by using different words.E.g., politicians: “revenue enhancement”= tax increase

Other Euphemisms• Oral hygiene appliance• Media courier• Negative patient care outcome • Vertical transportation corps • Social expression products • Preemptive counter attack • Given an alternative career opportunity • Being economical with the truth• Unscheduled terrain encounter

Human Language

But do different languages facilitate different thoughts?E.g., Dani people of New Guinea• 2 basic words for color: mili & mola• So do they have difficult discriminating colors? • “Whorf” hypothesis: Language determines the way we think=> people who speak different languages think differently. => Dani should not be able to think about different types of colors. • BUT research (Rosch) shows Dani make as many discriminations between colors as people who have many more basic color terms

Human Language

• Genes design the mechanisms for a language, and experience activates them as it modifies the brain

Genes

Environment:spoken language

heard

Brain:mechanisms for

understanding andproducing language

Behavior:mastery of

native language

provides input to

design

Language Development

New language learning gets harder with age

100

90

80

70

60

50Native 3-7 8-10 11-15 17-39

Percentage correct ongrammar test

Age at school

Learning Foreign Languages

Intelligence

What is intelligence?

• Cognitive ability → the ability to perform well in cognitive tasks

• The ability to use knowledge, solve problems, understand complex ideas, learn quickly, and adapt to environmental challenges

Issues in the study of intelligence

• Can intelligence be quantified?

• Is it fair to use measures of intelligence in situations that can affect people’s life outcomes?

• Is intelligence more determined by genetics or environmental factors?

• Are their racial differences in intelligence?

Francis Galton

1. Intelligence is quantifiable (i.e., numerical values can be assigned to distinguish between people’s level of intelligence)

2. Differences among people form a Bell shaped curve

IntelligenceLow

Frequency

High

British scientist who wrote “Hereditary Genius” in 1869, suggesting that genius is heritable because it runs in families

3. Intelligence can be measured by objective tests

4. People’s scores on different tests are correlated

Francis Galton

Founded “Eugenics”: advocates improving human species by applying evolutionary theory to encourage “biologically superior” people to interbreed

Alfred Binet

France, 1904: Commissioned to develop techniques to identify children in need of special education

Designed first intelligence test (series of short tasks not relying on reading skills)

Did not believe intelligence was fixed or inherited

Lewis Terman

Stanford University, 1916: Brought Binet’s intelligence test to US → Stanford-Binet test

Designed to be administered in a standardized fashion to large numbers of people

E.g., Immigrants at Ellis Island; 1.75 million soldiers in WW2

Immigrants measured according to country of origin

Nordics > Southern Europeans & Slavs > Blacks

=> stricter immigration policy in 1924

But this was overlooked:

Blacks from Northern states > Blacks from Southern states

Europeans in US for longer > those in US for shorter period

Examples of items on Stanford-Binet Test

Age Sample test item 2 Here are some pegs of different sizes and shapes.

See whether you can put each one into the correct hole 4 Why do people live in houses? 6 Here are some candies. Can you count how many there are? 10 Why should people be quiet in the library?   12 What does “regret” mean?  14 What is the similarity between high and low?

What does an IQ test reflect?

E.g., If you had a mental age of 10 when you were 8 years old, you IQ would be 125

IQ = M.A. X 100 = 10 X 100 = 125C. A. 8

IQ range100 average90-110 normal rangeabove 120 superiorbelow 70 developmentally disabled

 

Intelligence Quotient (IQ) = Mental Age X 100Chronological Age

An example of an IQ test (though not a good one) is the SAT2 sets of multiple choice items (verbal & quantitative)

Can we improve our SAT scores with coaching?

Yes, but not by much: 10-20 points on the normal 200-800 range

What does an IQ test reflect?

What do we mean by “intelligence?”

• What does the Stanford-Binet test actually measure?

• What do we want to measure with IQ tests?

• What do modern IQ tests measure?

• Are IQ tests valid? (Do they measure what they are intended to measure?)

The “g” factor

Mechanicals

Spatials

Logicals

Arithmeticals

g

Spearman

What does “g” determine?

• Educational achievement

• Occupation

• Income level

• Probability of divorce

• Health

• Longevity

• Which of the following factors do you think are associated with school-aged children’s performance on standardized test scores?– The child has highly educated parents– The child’s family is intact– The child’s parents have high socioeconomic status– The child’s parents recently moved to a better neighborhood– The child’s mother was thirty or older at the time of her first child’s

birth– The child’s mother didn’t work between birth and kindergarten– The child had low birthrate– The child attended Head Start– The child’s parents speak English in the home– The child’s parents regularly take him to museums– The child is adopted– The child is regularly spanked– The child’s parents are involved in the PTA– The child frequently watches television – The child has many books in his home– The child’s parents read to him nearly every day

What determines “g”?

• The child has highly educated parents• The child’s family is intact• The child’s parents have high socioeconomic status• The child’s parents recently moved to a better

neighborhood• The child’s mother was thirty or older at the time of

her first child’s birth• The child had low birthweight• The child attended Head Start• The child’s parents speak English in the home• The child’s parents regularly take him to museums• The child is adopted• The child is regularly spanked• The child’s parents are involved in the PTA• The child frequently watches television• The child has many books in his home• The child’s parents read to him nearly every day

What determines “g”?

• Genetics?

• Environment?

• Genetics + environment (education + nutrition + culture + family + brain exercise…)

• But how great is the role of genetics?

Genetic influences on intelligence

Monozygotic (identical) twins

Dizygotic (franternal) twins

Are there racial differences in intelligence?

• Reasons to consider the question:– Genetics do affect intelligence– Races differ genetically, though not by much– Reliable group differences have been found– What causes group differences?– It is a testable question

Reliable differences have been found on IQ scores between racial groups. In America today:

Average IQ scoreBlacks 85Hispanics 94Whites 100Asians 106Ashkenazi Jews 109

[keep in mind that these scores are averages for entire population -- some Blacks score higher than some Asians on IQ tests]

Are there racial differences in intelligence?

Herrnstein & Murray (1994): “The Bell Curve”

Evidence from large group of white subjects, followed for 10 years

high IQ scores predicted getting into a good college, success in college, getting a good job, and success at the job

low IQ scores predicted having illegitimate children, going on welfare, and committing a crime

Pointed out 2 things we have already noted:

Intelligence is heritable

There are differences in IQ between racial groups

 Conclusion: racial differences in IQ are due genetic differences and that these genetic differences explain behavioral differences between races.

Possible explanations for observed racial differences in IQ scores

1. Blacks are genetically predisposed to have lower IQBUT within-group differences do not explain between group genetic effects

Poor soil Fertile soil

Variation within group

Variation within group

Differences between groups

Possible explanations for observed race differences in IQ scores

1. Blacks are genetically predisposed to have lower IQ

2. Blacks & whites are raised in different environments (physical & psychological)

When blacks & whites matched for socioeconomic factors, IQ differences diminishBut could matching ever be complete?

Claude Steele

“Stereotype threat”: fear of doing something that would inadvertently confirm a negative stereotype

Experiment:

IQ-matched Black & white subjects take difficult test

Condition ATold nothing

Condition BTold no race differences

Blacks do relatively poorly

No differences between Blacks & Whites

Stanford University

Possible explanations for observed race differences in IQ scores

1. Blacks are genetically predisposed to have lower IQ

2. Blacks & whites are raised in different environments (physical & psychological)3. Tests are racially biased

Gosling’s Intelligence Test (GIT)

1. In a game of cricket, David scored all of his 22 runs from sixes and boundaries. He got one six. How many boundaries did he score?2. Who designed St. Paul’s cathedral in London?3. What is the official address of the British Prime Minister?4. Red is to the Central Line as is to the Northern Line5. Neil Kinnock was to Margaret Thatcher as is to Tony Blair.6. In David’s second innings he had to run all 5 of his runs. How many yards did he run?7. What kind of programs would you expect to hear on BBC radio 3?8. David Gower was to cricket as Will Carling was to ?9. Andrew is to Scotland as is to Wales10. If Ophelia traveled at the speed limit on a motorway for two hours, how many miles will she have traveled?

Possible explanations for observed race differences in IQ scores

1. Blacks are genetically predisposed to have lower IQ

2. Blacks & whites are raised in different environments (physical & psychological)3. Tests are racially biased

In terms of common IQ tests, evidence for bias is mixed – most modern tests are not biased, though historically, many tests have been

Conclusions: Genetic factors clearly play a role in people’s intelligence, but there is no clear evidence that genetic factors account for observed IQ differences in Black & White Americans

Genetic Relatedness and IQ Correlation

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