Thinking, Language,
and Intelligence
Chapter 8
Thinking, Language, &
Intelligence
Thinking
 Solving Problems
 Making Good (and Bad)
Decisions and Judgments
 The Perils and Powers of Intuition
Thinking, Language, &
Intelligence
Language
 Language Development
 Thinking Without Language
 Animal Thinking and Language
Thinking, Language, &
Intelligence
Intelligence
 What Is Intelligence?
 One General Intelligence or Multiple
Intelligences?
 Assessing Intelligence
 The Nature and Nurture of
Intelligence
 Group Differences in Intelligence
Test Scores
Thinking
The study of cognition focuses on the mental
activities associated with thinking, knowing,
remembering, and communicating.
Method of Solving Problems
• Trial and Error
• Algorithms – step-by-step procedures
that guarantee reaching a solution
• Heuristics – rules of thumb, simple
strategies. Speedier but more error-prone
than algorithms
• Insight – a sudden realization of a
problem’s solution. An aha! moment
Insight and the Brain
• Study: which word will form
a compoud word with: pine,
crab, sauce?
• Measureed brain activity
with fMRI and EEG
• Aha! moment preceded by
frontal lobe activity
(focusing attention) and
then burst of activity in right
temporal lobe
Quick-Thinking Heuristics
• Heuristics are useful for making quick decisions
• Sometimes, they can get us into trouble
• Kahneman and Tversky, among others, have
identified many heuristics that people use, and
the associated pitfalls
The Availability Heuristic
• We may base our judgements on how
quickly and easily an event comes to mind
• Often right, but not always
• Does the letter k appear more often as the
first or third letter of a word?
– Most people say the first, but words like know,
kingdom, king are outnumbered 5 to 1 by
words like make, like, asked, etc.
Fixation
• Some heuristics can lead to fixation, the
inability to see a problem from a fresh
perspective
How can you arrange six matches to form
four equilateral triangles?
Fixation
People often become fixated on twodimensional solutions
Confirmation Bias
• We tend to search for information that supports
our preconceptions and ignore, distort, or forget
to seek evidence against our ideas
• Wason (1960): Guess the rule for the following
sequence. You may give your own sets and see
if they work with the rule:
2-4-6
• They were seldom right but never in doubt. (The
rule: each subsequent number must be larger)
Overconfidence
• Overconfidence: we overestimate the
accuracy of our beliefs and decisions
– Example: we tend to overestimate our future
free time
• It’s adaptive: self-confident people are
happier, make tough decisions more
easily, and seem more believable to
others
Framing
• Framing, the way an issue is posed, can
significantly affect decisions and judgments
• “Are these condoms effective if they…”
– “…have a 95% success rate?” 9 in 10 said yes.
– “…have a 5% failure rate?” 4 in 10 said yes.
• Organ donors
– “Opt out” countries – nearly 100% donors
– “Opt in” countries (including U.S.) – only 25% donors
Those who understand the power of framing can
use it to influence our decisions
Our Beliefs Live On
• Belief perseverance – we cling to beliefs and
ignore evidence that proves they are wrong
• One way to combat this is to consider the
opposite – imagine if the evidence had the
opposite results, what would you think?
• Study: Students would not let facts change their
belief –The death penalty is/is not an effective
deterrent.
The Perils and Powers of Intuition
• Intuition is used often. Much of our thinking occurs “offscreen”
• Intuition is adaptive. Fast and frugal heuristics allow us
to react quickly and often reliably
• Intuition is recognition born of experience, or
“analysis frozen into habit”
• Intuition can sometimes be perilous, guiding us in
the wrong direction. Especially when we overfeel and
underthink. We must check our intuitions against reality
Language
• Language consists of our spoken, written, or
signed words and the ways we combine them to
communicate meaning
• The evolution of language was a huge leap
forward for our species. We can communicate
information from one individual to the next, and
from one generation to the next.
Language Development
• About 50% of our speech consists of only 150
words, but by high school we know about 60,000
words!
• How did we learn these words?
• How do learn our language’s syntax (the correct
way to form words into sentences)?
When Do We Learn Language
• Infants start without language
• At 4 months, can recognize speech sounds and
enter babbling stage, uttering various sounds
(ah-goo)
– Around 10 months, babbling sounds more like
parents’ language
• Around 1 year, enter one-word stage, speaks
primarily in single words (“Doggy!”)
• By age 2, enter two-word stage, which involves
so-called telegraphic speech (“Want juice!”)
How Do We Learn Grammar?
• Chomsky: All languages share a
universal grammar – e.g., nouns, verbs,
adjectives
• Humans are built with a built-in readiness
to learn language
• Childhood is a critical period for learning
language – must be exposed by age 7
New Language Learning Gets Harder With Age
Grammar test
given to Asian
immigrants ten
years after
arriving in the
U.S.
Thinking Without Language
• We often think in images
• Mental practice can be valuable for musicians,
athletes, and others
• Once you have learned a skill, watching others
perform it or imagining it can trigger activity in
the same brain areas
The Power of Imagination
• Imagining the
experience of pain
activates some of
the same brain
regions as the actual
experience
Animal Thinking and Language
• Animals are smarter than you may realize
• Forming concepts
– Shown a picture of a new chair, pigeons can peck a
key that means “chair”
– Great apes (e.g., chimps, gorillas) can form concepts
like “cat” and “dog”.
– Clusters of frontal lobe neurons will then fire to new
“cat-like” objects, for instance
Animal Thinking and Language
• Numerical ability
– Irene Pepperberg trained
Alex, a grey parrot, who
could name and categorize
objects, and count up to six.
– Alex could add clusters of
objects, and respond to
questions like “What color
four?” with the correct color
of the objects in a group of
four.
Animal Thinking and Language
• Displaying Insight
– Köhler (1925) placed a piece of fruit and a long stick
outside the cage of Sultan the chimpanzee, outside
his reach
– Inside the cage was a short stick.
– After several failed attempts, Sultan paused and then
used the short stick to reach the long stick, and in turn
the fruit!
Animal Thinking and Language
• Tool use
– Forest chimpanzee use many different tools
• a heavy stick for making tools
• Light, flexible stick for termite fishing
– Researchers have found over 39 local customs
related to chimpanzee tool use, grooming, and
courtship.
• One group may slurp termites right off the stick, others
may pluck off individually
Mother chimp teaches her young to
use a stone hammer
Animal Thinking and Language
• Cultural Transmission
– Group differences in chimpanzee customs are not
genetic, but cultural.
– Chimpanzees invent behaviors and transmit them
culturally to peers and offsprings, as do orangutans
and dolphins
– Some dolphins have learned to
use sea sponges to protect
their nose while probing the sea
floor for fish
Animal Thinking and Language
• Animals have many other cognitive skills
– A baboon knows the voice of each individual in its
80-member troop
– Sheep can recognize and remember individual faces
– Chimps and some monkeys can read a human’s
intent from her facial expression
– Great apes, dolphins, and elephants can recognize
themselves in a mirror
– Chimpanzees have shown altruism, cooperation, and
group aggression
Do Animals Have Language?
• Animals show impressive
comprehension and
communication
– Vervet monkeys have different
alarm calls for different predators
– eagle, leopard, snake.
– Rico the border collie has a 200word vocabulary.
• But is it language?
Do Animals Have Language?
• In the 1960s, Gardner and
Gardner taught Washoe the
chimpanzee sign language
– She could use up to 181
signs
– Sentences were very simple
– “You me go out, please.”
– Creative combinations –
“water bird” for a swan
– Another Chimp, Louis,
learned the signs directly
from Washoe
Criticisms of Chimpanzee Language
• Vocabulary and sentences are simple, like that
of a 2-year-old human
– Apes gain their limited vocabulary only with great
difficulty
• Chimps can make signs or push signals for a
reward. Is this just conditioning?
• Perceptual set – are we just seeing what we
want to see?
• Chimps lack human syntax
The Case for Chimpanzee Language
• Kanzi, a bonobo, could understand syntax in
spoken language
• Like humans, early life in chimps may be the
critical period for language
• If language means verbal or signed expression
of complex grammar, only humans have
language
• If we mean only the ability to communicate
through a meaningful sequence of symbols, then
apes are also capable of language
What Is Intelligence?
• Intelligence is the ability to learn from
experience, solve problems, and use
knowledge to adapt to new situations
• The definition can vary depending on
context or culture
General Intelligence
• Charles Spearman (1863-1945) believed
we have one general intelligence (g) at
the heart of all intelligent behavior
• Individuals who do well in one area tend to
do well in other areas
Savants
• General intelligence doesn’t explain those with
savant syndrome, in which a person with
otherwise limited mental ability has an
exceptional specific skill
• Savant artist Stephen
Wiltshire drew the Tokyo
skyline from memory after
a 30-minute helicopter ride
and a visit to the top of a
skyscraper
Multiple Intelligences
• Howard Gardner has identified 8 relatively independent
intelligences
• However, factor analysis research has confirmed that
there is a general intelligence factor, g
Creativity
• Creativity is the ability to produce new
and valuable ideas
• Requires a certain level of intelligence, but
is not the same thing
• Exceptionally creative architects,
scientists, and engineers are usually no
more intelligent than those of their less
creative peers
What is Creativity?
• Five necessary parts (Sternberg, 1988,
2003)
1.
2.
3.
4.
5.
Expertise
Imaginative thinking skills
A venturesome personality
Intrinsic motivation
A creative environment
Emotional Intelligence
• Emotional intelligence is the ability to perceive,
understand, manage, and use emotions.
– Part of social intelligence
• Emotionally intelligent people tend to avoid
being overcome by emotion, perform better on
the job, and can delay gratification for longrange rewards
– Often succeed in domains where academically
smarter but emotionally less intelligent people fail
Assessing Intelligence
• Intelligence can be considered defined as
measured by intelligence tests
• Psychologists started measuring
intelligence in the early 20th century
– Some measured aptitude – the ability to learn
– Some measured achievement – what people
have already learned
Alfred Binet
• Developed early intelligence
tests based on new laws
requiring all children to attend
school
• Assumed all children follow the
same intellectual development
path, but at different rates
• Coined the idea of mental age,
the chronological age that most
typically corresponds to a given
level of performance
Measuring IQ
• Lewis Terman, a professor at Stanford,
revised the Stanford-Binet test
• This test reported a person’s intelligence
quotient:
mental age
IQ 
chronological age
 100
• Today, intelligence tests represent
performance relative to average
performance
of others the same age

Separate Scores for Separate Skills
The Wechsler Adult Intelligence Scale (WAIS) is
the most widely used intelligence test
– Contains verbal and performance (nonverbal) subtests
Tests of a “Good” Test
• Was the test standardized?
• Is the test reliable?
• Is the test valid?
Standardization
• Standardization defines scores by comparing
them with a pretested group (representative
sample of people)
• Graphs of test-taker’s scores typically form the
normal curve
Reliability and Validity
• Reliability is the extent to which a test
yields consistent results
• Validity is the extent to which a test
measures or predicts what it is supposed
to
• A two-foot “yardstick” would be reliable,
but not valid
Intelligence: Nature and Nurture
• Intelligence runs in families – but why?
Twin Studies
• Genes matter: Identical twins highly correlated
• Environment matters: fraternal twins, compared to
non-twin siblings, are more alike in intelligence but
not in genes
Adoption Studies: Surprising?
• Mental similarities
between adopted children
and their adopted families
decrease with age
• Similarities with biological
parents increase as
children gain life
experience
• Does this support the
nature or nurture view of
intelligence?
Heritability
• Heritability is the portion of variation among
individuals attributable to genes
– The heritability of a trait can vary depending on the
population and the environment
• Intelligence is usually about 50% heritable
– Means that heredity is responsible for 50% of the
variation in intelligence studied
• Our genes shape the experiences that shape us
– Taller children picked for basketball, get more
practice, more coaching, and be better at basketball
later
Environment and Intelligence
• Malnutrition, sensory deprivation and social
isolation early in life can permanently impact
intelligence
• Infants need care that responds to their own
inputs, so they develop a sense of personal
control over their environment
• However, there is no recipe for turning babies
into geniuses
Ethnic Differences
Two disturbing but agreed-upon facts:
• Racial groups differ in their average intelligence
score
• High-scoring people (and groups) are more
likely to have high levels of education and
income
• E.g., average score for blacks is ten points less
than for whites
• But the normal curves overlap: group differences
provide little basis for judging individuals
Might the Racial Gap Be
Environmental?
• Even if variation between groups correlates with
genetic differences, the average difference
between groups may be wholly due to the
environment, e.g. education, poverty
Might the Racial Gap Be Environmental?
• Under the skin, races are highly alike
– Average genetic difference between two Icelanders or
two Kenyans is greater than group difference
between Icelanders and Kenyans
• Race is not a neatly defined biological character
• There are generation-to-generation differences
with the same population
– Today’s you are better-fed, better-educated, and
more test-prepared than those of previous
generations
• Infants score equally well on intelligence
measures regardless of race
• Schools and culture matter
Gender Differences
• In terms of the ways we think, feel, and
act, gender similarities vastly outnumber
differences.
• No differences in general intelligence, g
• Still, there are some differences in ability
level between men and women
Gender Differences
• Verbal memory. Females excel at verbal fluency, are
better spellers, and have better memory for facts.
• Nonverbal memory. Females are better at locating
objects, and at associations with pictures and sensory
information.
• Emotion-detecting. Females are better at detecting
emotion and intent from expression
• Math aptitude. Males tend to be better, but only in
cultures that associate being male with science and
math.
Gender Differences
• Spatial abilities. Most reliable male edge. Males do
better at mental rotation. Thought to be evolutionarily
related to tracking prey and returning home. Also may be
due to experience with play using spatial abilities.
• Greater male variability. Males’ scores vary more than
females – they outnumber females at both the low and
high extremes.
Are Test Questions Biased
• May be biased by a person’s culture experience
• In terms of prediction, they are not biased –
predictive validity is the same for all groups
Stereotype Threat
• Some may feel that their performance will
support others’ stereotypes of their group – this
is stereotype threat.
– Women underperformed on a math test except when
they were told that women usually do as well as men
on the test
• Danger: telling people they need help might hurt
their performance
• Countering this effect: Self-affirmation can
improve performance
The Bigger Picture
• Intelligence scores do not portray a whole
person; for example, they do not describe
the skills and dedication of someone
devoted to helping others.