Title: Chapter 8 Cognition and Language
1Chapter 8Cognition and Language
2Cognition and Language
- Cognition refers to thinking, gaining knowledge,
and dealing with knowledge. - Language is intimately related to the activities
of cognition. It is a system of arbitrary symbols
that can be combined to create an infinite number
of meaningful statements.
3Module 8.1
- Thinking and Mental Processes
4Cognitive Psychology
- Cognitive psychologists study how people think,
acquire knowledge, what they know, what they
imagine and how they solve problems. - Cognitive psychology uses a variety of methods to
measure mental processes and test theories about
what we know and how we know it.
5Categorization
- The formation of categories or concepts is one of
the primary ways that we organize information
about our world. - In general we categorize people, objects or
events together when they have important
qualities in common. - There are a number of ways to categorize.
6Categorization
- Prototypes
- A prototype is a familiar or typical example of a
category. - By using prototypes, we decide whether or not an
object belongs in a category by determining how
well it resembles the prototypical members of the
category
7Categorization
- Prototypes
- We use ROSE as the prototypical flower.
- Daisy and tulip resemble it closely enough that
you would quickly agree that they belong in the
same category. - What about the corpse flower which has a
blossom that is not colorful and a terrible
fragrance? Although you would also classify it as
a flower, you would pause because it doesnt
resemble the prototype in some important ways.
8Categorization
- Prototypes
- The prototype approach suggests that membership
is a category may be a matter of degrees, not a
yes-or-no question. - Prototypes are harder to apply to compound
categories. - We can discuss a category without having an
existing example of its members. - Try to think of a prototypical rare insect.
- Do we require a prototype to discuss or think
about extinct amphibians?
9(a)
(b)
- Figure 8.1
- (a) A much-abridged chart of the current
scientific classification of the animal kingdom.
(b) An alleged listing from an ancient Chinese
encyclopediaactually the product of someones
imagination (Rosch, 1978). The point is that some
methods of categorizing are better than others.
10Categorization
- Cross-Cultural Studies of Concepts
- We tend to assume that everyone in the world
forms categories the same way, but this is not
correct. - Words for colors vary among world languages.
- People probably see colors the same way, but we
dont know if red in one language is the same
red as in English. It could be a variation of
red (orange-red.) - The Dani people of New Zealand have no words for
colors at all just light and dark.
11- Figure 8.2
- Elizabeth Rosch Heider asked people to look at a
color sample, such as one of these, remember it
for 30 seconds, and then pick it out from an
array of 160 choices. Her hypothesis was that
people would remember more accurately the focal
colors than the boundary or internominal colors.
12Categorization
- Conceptual networks
- Thinking about something usually means relating
it to a network of related concepts. - Its difficult to think about something by
itself. - We have a hierarchy in mind of categories and
subcategories. - The upper levels of the hierarchy are the more
common, broadly shared characteristics. - The lower levels are the more distinctive or
special characteristics. - This simplifies the process of classifying.
13CONCEPT CHECK
- Which question takes longer to answer
- Do astronauts travel in spaceships?
- Do astronauts sometimes get traffic tickets?
The first one is a more distinct feature and
should be easier to answer (although both are
true.)
14Categorization
- Conceptual networks
- When you hear about one concept, the other
concepts that you associate with it are also
primed or activated. - This process is called spreading activation.
- If you hear the word car you think of drive
or road. What do you think of when you hear the
word school?
15- Figure 8.4
- According to one explanation, the word Armstrong
and the ideas astronaut, first person on the
moon, and famous sayings all activate the linked
saying One small step for a man . . . Even the
word Louis contributes because both Louis
Armstrong and Neil Armstrong were famous people.
16Attention
- Preattentive and attentive processes
- It is generally true that a feature or object
that is unusual or different will get your
attention quickly, while one that is surrounded
by similar objects will require a long and
patient search. - Finding an unusual feature or figure relies on a
preattentive process, a procedure for extracting
information automatically or simultaneously
across a large portion of the visual field. - Finding a typical feature or figure requires an
attentive process, a procedure that considers
only one part of the visual field at a time.
17- Figure 8.5
- Demonstration of preattentive processes Find the
vertical line in each part. Most people find it
about equally fast in both parts.
18- Figure 8.6
- Demonstration of attentive processes Find the
pentagon pointing down in each part. Most people
take longer to find it in part b.
19Attention
- Preattentive and attentive processes
- The Stroop effect is another example of the
difference between preattentive and attentive
processes. - Although it is difficult to explain, it seems
that reading for most of us is an automatic and
preattentive process. - Being asked to refrain from reading and name the
colors instead makes substantive demands on
attention.
20- Figure 8.7
- Read (left to right) the color of the ink in each
part. Try to ignore the words themselves. Your
difficulty on the lowest part illustrates the
Stroop effect.
21Attention
- Shifting attention
- Many routine tasks that we perform require little
attention. - When we intentionally shift our attention to a
particular stimulus, we often lose attention to
everything else. - Negative priming occurs when we attend to one
thing and deliberately ignore another. We may
briefly find it hard to identify the previously
ignored stimulus.
22Attention
- Shifting attention
- A related effect is the attentional blink.
- During a brief time after perceiving one
stimulus, it is difficult to attend to something
else. - Effects such as these are of crucial importance
in both the trivial activity of playing a video
game, and potentially life-and-death situations
such as flying an airplane or operating other
complex machinery.
23- FIGURE 8.9
- Each gauge represents a measurement of a
different variable in a machine, such as an
airplane. The top row shows one way of presenting
the information. The operator must check each
gauge one at a time to find out whether the
reading is within the safe range for that
variable. The bottom row shows the information
represented in a way that is easier to read. The
safe range for each variable is rotated to the
same visual position. At a glance the operator
can detect any reading outside the safe zone.
24Mental Imagery
- Sometimes people will report that they have no
trouble creating a mental picture of an object or
location, but still they cannot answer questions
about it correctly when those questions are based
on the mental image. - Our mental images are frequently wrong in many of
their details.
25Mental Imagery
- Which city is farther north, Seattle, WA or
Montreal, in the province of Quebec, Canada?
Seattle is farther north, but our cognitive maps
are biased by this heuristic - Canada is north
of the US, therefore all its cities are north of
all of ours.
26- Figure 8.12
- Logical versus actual location of Reno and Los
Angeles. Most people imagine that Los Angeles is
farther west because California is west of Nevada.
27Mental Imagery
- Cognitive Maps
- A mental image of a spatial arrangement is called
a cognitive map. - Cognitive maps (at least versions that are drawn
by research subjects) tend to exhibit interesting
patterns of error. - Cognitive maps highlight some details, distort
some, and omit some details altogether.
28Mental Processes
- Many of these findings we have described are
based on research involving self-report of
subjects concerning their mental processes. - Remember that conclusions based on such findings
are tentative. - We strengthen them by performing many studies,
using different methods, and looking for
consistent results.
29Module 8.2
- Problem-solving, Expertise, and Error
30Expertise
- People vary in their performance on
problem-solving and decision-making tasks. - Those whose abilities are particularly advanced
we refer to as experts. Expert performance goes
a step beyond what is typically expected in
completion of a task.
31Expertise
- Practice effects
- Our first inclination is to attribute expert
abilities to special, inborn talents. - Studies show that expert abilities are most often
the result of practice. - Those who show advanced abilities in an activity
usually begin learning it at a younger age and
spend more time in concentrated practice. - The rule-of-thumb is that developing expertise
takes about 10 years of concentrated practice.
32Expertise
- Expert Pattern Recognition
- Experts are especially good at looking at
patterns and recognizing important features
quickly. - This talent is most evident when we consider a
demanding visuospatial game such as chess. - It is true however that in many other activities,
from bird watching to reading PET scans, that
pattern recognition is a key skill possessed by
experts.
33Problem-Solving
- The 4 phases of problem-solving
- Understanding the problem
- Generating one or more hypotheses
- Testing the hypotheses
- Checking the result
34- Figure 8.15
- The four steps to solving a problem.
35Problem-Solving
- Algorithms
- When a problem is well defined, we can apply an
algorithm to solve it. - An algorithm is a mechanical, repetitive,
step-by-step procedure for arriving at the
solution to a problem. - Mathematics is a field of knowledge made up
primarily of algorithmic problem solving. - The steps for programming your VCR also comprise
an algorithm. Do you know it?
36Problem-Solving
- Heuristics
- Many problems that we face are too ill defined
for the use of any algorithm. - An example of such a problem would be What
career would be best for me? - For less well defined problems we apply
heuristics. Heuristics are strategies for
simplifying a problem or guiding an
investigation.
37Problem-Solving
- Insight
- Using insight to solve a problem differs from
using algorithms. - Most people can look at a mathematical problem
and accurately gauge whether or not they would be
able to solve it. - Insight strategies are used in cases where we
have no idea whether or not we would be able to
solve the problem. - Insight solutions often seem to be arrived at
suddenly.
38Problem-Solving
- Insight
- It is probably the case that we work on insight
problems without realizing that we are doing so. - We are making use of the information that we have
already stored related to the problem. - Even when subjects in insight problem-solving
studies claim to have no confidence in their
abilities to arrive at the solution, they do so a
majority of the time.
39- Figure 8.19
- (a) Draw the trajectory of water as it flows out
of a coiled garden hose. (b) Draw the trajectory
of a bullet as it leaves a coiled gun barrel.
40- Figure 8.18
- What is wrong with this perpetual motion machine?
41Problem-Solving
- The Characteristics of Creativity
- Creativity is not the same as expertise.
- Creative individuals tend to be less consistent
in the quality of their output that are experts. - You are probably aware of this variation in the
collected work of your favorite musician, for
example.
42Problem-Solving
- The Characteristics of Creativity
- Here are some of the characteristics held in
common by creative individuals - Nonconformity
- Risk-taking
- Willingness to tolerate rejection
- Openness to new experience
- At least a moderate level of intelligence
- It is important to keep in mind though that this
creativity is usually restricted to one area or a
related set of areas that the creative person
knows well.
43Problem-Solving
- The Characteristics of Creativity
- Some other similarities among creative people,
based on the work of Howard Gardner - An atmosphere of moderate tension, and a sense
that change was necessary. - Sufficient background to feel confident in
knowledge of the area and its problems. - At least one mentor or friend who provided advice
or encouragement. - A high level of commitment to the work,
sacrificing any possibility of a well-rounded
life.
44Problem-Solving
- Common Errors of Human Cognition
- Critical thinking involves using our considerable
ability to evaluate our own thinking (called
metacognition) to carefully evaluate for and
against any conclusion. - All thinkers make these errors, and monitoring
our cognition can be a demanding activity, but
the clarity and knowledge that we can achieve by
doing so makes the effort well worth it.
45Problem-Solving
- Common Errors of Human Cognition
- Overconfidence is our belief that our answers are
more accurate than they actually are. - We tend to be overconfident about our answers to
difficult questions. - We are underconfident about our answers to easy
questions, because statistically it is hard to be
overconfident about answers that are entirely
correct.
46- Figure 8.22
- At the beginning of a semester, undergraduates in
an advanced psychology course estimated their
probable semester grade. Students with low,
medium, or high grade- point averages generally
predicted that they would get an A or a B. The
best students were slightly overpredicting their
success the worst students were greatly
overpredicting. (Based on data of Prohaska, 1994)
47Problem-Solving
- Common Errors of Human Cognition
- People are also overconfident about their
accomplishments. - Ahead of the fact, we will overestimate the
quality of our predicted performance. - After the fact, we will overestimate the quality
of our past performance. - Research studies of ordinary people and experts
are consistent in supporting these tendencies.
48- Figure 8.24
- You are provided with a candle, a box of matches,
some thumbtacks, and a tiny piece of string. What
is the best way, using no other equipment, to
attach the candle to a wall?
49Problem-Solving
- Common Errors of Human Cognition
- Sometimes we commit to an explanation or
hypothesis before we have all the available
information on the problem. - Premature commitment to a hypothesis can lead us
to fail to consider other plausible possibilities
and fail to arrive at the correct answer. - Functional fixedness is one special case of
premature commitment. - It is the tendency to adhere to a single approach
to a problem or a single way to use an item.
50Problem-Solving
- Common Errors of Human Cognition
- The representativeness heuristic is the tendency
to assume that if an item is similar to members
of a particular category, it is also a member of
the category. - If it looks like a duck.
- It is better to make these judgments in light of
the available base-rate information, that is, the
data about the frequency or probability of a
given item or event. - People tend to use only the representativeness
heuristic and fail to consider the frequency data.
51Problem-Solving
- Common Errors of Human Cognition
- The availability heuristic is the strategy of
assuming that how easily one can remember
examples of an event is an indicator of how
common that event actually is. - For example, it is easier to think of examples of
people dying from car crashes than from stomach
cancer, so you assume that you are more likely to
die in a car crash. - You are somewhat more likely to die from stomach
cancer. The actual base rate of digestive cancer
is the higher one.
52- Table 8.1
- The Representativeness Heuristic and the
Availability Heuristic
53Problem-Solving
- Common Errors of Human Cognition
- The way a question is framed or presented can
also influence the way in which we answer it. - The tendency to answer a question differently
when it is phrased differently is called the
framing effect. - This effect is important to keep in mind for
those who need to persuade.
54- Figure 8.25
- When Amos Tversky and Daniel Kahneman (1981)
offered these choices to more than 150 people,
72 chose A over B, and 78 chose D over C.
However, plan A is exactly the same as plan C
(200 live, 400 die), and plan B is exactly the
same as plan D. Why then did so many people
choose both A and D? The reason, according to
Tversky and Kahneman, is that most people avoid
taking a risk when a question is phrased in terms
of gain, but they are willing to accept a risk
when the question is phrased in terms of loss.
55CONCEPT CHECK
- 50 of all military personnel prefer to watch TV
talk shows, but only 10 of all middle-aged
people do. So more watchers of TV talk shows are
military personnel. - What information would you need to assess the
accuracy of this statement?
The base rates How many military personnel are
there? How many middle-aged people?
56- My friend gives me a crystal and says if I wear
it everyday I will remain healthy. I wear it and
remain healthy. So I conclude that the crystal is
causing me to remain healthy. - What do you think?
Premature commitment to the hypothesis There are
many other reasons that I might remain healthy.
57Problem-Solving
- Common Errors of Human Cognition
- If you spend 70.00 on tickets to an event, but
you feel sick and miserable on the evening of
that event would you go anyway? - If you were given tickets to the same event, but
you felt sick and miserable on the evening of the
event, would you go anyway? - People are more likely to go if they have spent
their own money. This is the sunk cost effect. - The sunk cost effect is our tendency to do
something that wed otherwise choose not to do,
just because we spent the money to do it.
58Problem-Solving
- The Psychology of Gambling
- Gambling has been a common behavior in all world
cultures throughout history. - There are identifiable patterns of thought that
promote this behavior.
59Problem-Solving
- The Psychology of Gambling
- We tend to overestimate our control over chance
outcomes. - Giving people the illusion of control increases
their willingness to gamble. - We feel more likely to win the lottery when we
choose our own ticket and numbers than when
someone just gives us a ticket.
60Problem-Solving
- The Psychology of Gambling
- We appear to have an affinity for picking a slim
chance of a big gain over a sure but small
profit. - The low probability of winning may be part of the
appeal. - People report more pleasure from a surprising
gain than from one that was expected.
61- Table 8.2
- Expected Winnings on a 1 Decco Ticket (a
California Lottery Game)
62Problem-Solving
- The Psychology of Gambling
- As we learned earlier, schedules of reinforcement
are used to keep a desired behavior going after
its been learned. - Gambling is very similar to variable-ratio
reinforcement an unpredictable number of
responses eventually lead to reinforcement. - State lottery commissions and casino owners make
sure that spectacular wins are well publicized so
that vicarious reinforcement (social learning)
will occur with thousands of other potential
gamblers.
63Problem-Solving
- The Psychology of Gambling
- The availability heuristic also plays a role in
perpetuating gambling. Combined with vicarious
reinforcement, its a powerful motivator to start
and continue. - The need to boost up self-esteem by beating an
opponent, by winning motivates continuation
when the gambler has been losing, even to the
point of making wild and foolish bets in some
cases.
64Successful and Unsuccessful Problem-Solving
- We have examined some of our strengths
(creativity and expertise) and weaknesses (poorly
constructed heuristics and gambling) in
problem-solving. - Learning about the strengths and weaknesses of
our decision-making is a big step towards
improving the quality of our problem-solving
processes.
65Module 8.3
66Language
- As far as we can tell, although many species can
communicate by exchanging signals, only human
languages can truly be called productive. - Humans can express new ideas through language.
67Language
- Animal languages are comprised of prepackaged
messages. - Human languages communicate a deep structure, the
intended meaning of the words. - Almost any human language provides enough
vocabulary and grammatical variation that the
deep structures can be converted into many
differently arranged statements that still
represent the same idea. - Linguist Noam Chomsky called this quality of
language transformational grammar.
68- Figure 8.28
- According to transformational grammar, we can
transform a sentence with a given surface
structure into any of several other sentences
with different surface structures. All of them
represent the same deep structure, which is the
underlying logic of the sentence.
69Language
- This flexibility and creativity that our language
provides can also get us in trouble. - While picnicking in the meadow we saw hawks with
our binoculars. - Hawks have excellent eyesight and dont need
binoculars. - Seriously though, if we are not careful about our
use of transformational grammar, our intended
meaning may be unclear or as in this case,
ambiguous.
70Animal Language
- One of the first examples of an animal using
human language was Washoe the chimp, raised by
psychologists. - Through conditioning by researchers Washoe
developed an impressive vocabulary of 100 signs. - But Washoe used these signs almost exclusively to
make requests. - She rarely used them to describe things or make
new, original statements.
71Animal Language
- Bonobo chimpanzees show more facility with human
sign language. - They can refer to objects that they are not
requesting, they can describe past events and
respond well to spoken requests. - It is not entirely clear whether Bonobos are a
particularly bright species of great ape, or
whether the training was somewhat better than
that which Washoe received. - The Bonobos were exposed to human language very
early in life, and received a great deal of
observational exposure to humans using the signs.
72Human Specializations for Learning Language
- Language and General Intelligence
- Psychologists are trying to determine whether our
intelligence has caused our development of
language. - Some highly intelligent species of animal do not
develop a flexible language. - People with Williams syndrome have general
cognitive abilities classified in the IQ range
associated with mental retardation, but have
excellent facility with language. - It appears that language ability is not
synonymous with intelligence.
73Human Specializations for Learning Language
- Language Learning as a Specialized Capacity
- Psychologists divide into two broad camps
regarding human language learning. - Nativists, such as Chomsky and Steven Pinker,
believe that humans are born with a built-in,
brain based mechanism for learning language. - They refer to this as a language acquisition
device or a language instinct.
74Human Specializations for Learning Language
- Language Learning as a Specialized Capacity
- The basis for the nativist view of language
learning is the poverty of stimulus argument. - This argument states that children do not
encounter enough information in the environment
to learn or infer grammar, so they must be born
with the knowledge.
75Human Specializations for Learning Language
- Language Learning as a Specialized Capacity
- The information that children get may not be so
sparse though in almost all world cultures
parents make special concessions to infant
understanding in speech by using parentese, a
slow and high-pitched method of communication
that may enhance early language learning. - But even very young infants do start picking up
language rules very early, extracting a great
deal of information from what they hear.
76Human Specializations for Learning Language
- Language and the Human Brain
- Studies of the brain using persons with brain
damage and modern imaging techniques have allowed
us to identify two areas vital for the processing
and production of language.
77- Figure 8.31
- Brain damage that produces major deficits in
language usually includes the left-hemisphere
areas shown here. However, the deficits are
severe only if the damage is more extensive,
including these areas but extending to others as
well. Many areas of the human brain contribute to
language comprehension and production.
78Human Specializations for Learning Language
- Language and the Human Brain
- Brocas area is vital for using and understanding
grammatical devices prepositions, conjunctions,
prefixes, suffixes, and the like. - Wernickes area appears to be important for
naming objects and comprehending language. - People with damage to these areas develop
aphasias a term for various inabilities to
process or use language. - Language production and processing activates very
widespread areas of the brain.
79Human Specializations for Learning Language
- Stages of Language Development
- There is impressive evidence of the universality
of stages of language learning, including
identical stages of productive and receptive
language in young children of all world cultures,
young hearing impaired children, and hearing
children of deaf parents who are learning both
sign and spoken language.
80Human Specializations for Learning Language
- Stages of Language Development Productive
- Cooing and random vocalizations 3 months
- Distinct babbling 6 months
- Jargon (babbling with speech inflections) 10
months - Holographic speech (one word sentences) 12 to
15 months
81Human Specializations for Learning Language
- Stages of Language Development Productive
- Telegraphic speech (two word sentences) 24
months - Simple if grammatically uneven sentences 30
months - Large (1000 word) vocabulary and better sentences
3 years - Close to adult facility with speech 4 years
82- Table 8.3
- Stages of Language Development
83Human Specializations for Learning Language
- Children Exposed to No Language
- Children who do not receive much early exposure
to language do not develop a language of their
own nor do they learn human language well after
starting regular exposure. - The early lives of such children are unknown so
it is hard to know with any certainty if lack of
exposure is the only culprit.
84Human Specializations for Learning Language
- Children Exposed to No Language
- Some deaf children who do not receive exposure to
sign language invent their own sign languages,
which increase in complexity as they mature. - The unique sign languages of these children have
some interesting similarities (subject object
specifications for example.)
85Human Specializations for Learning Language
- Children Exposed to Two Languages
- Some children grow up in a bilingual environment,
receiving roughly equal exposure to two different
languages. - These children learn both languages equally well.
- If exposure to the second language begins early
in life, the representation and storage of the
languages in the brain is identical.
86Human Specializations for Learning Language
- Children Exposed to Two Languages
- Although exposure to two or more languages can
slow down the overall process of acquisition, it
bestows some long-term cognitive benefits as
well. - Adults who were raised in bilingual environments
show an enhanced degree of cognitive flexibility
in understanding that there are many ways to say
the same thing. - There are many practical advantages in being able
to communicate with speakers of other languages.
87Human Specializations for Learning Language
- Understanding Language
- Language production and comprehension can be a
very complex task. - A good reader reads simple sentences quickly and
complex or ambiguous sentences slowly. - Even a simple word is broken down into a sequence
of sounds that change depending on the
arrangement of those sounds.
88Human Specializations for Learning Language
- Understanding Language
- Readers and speakers of all languages must be
aware of the assumptions that underlie the use of
language. The same word may have more than one
meaning, for example, and context must be
considered in order to correctly use and
comprehend that word. - The use of negatives in a language adds further
complexity and possibility of erroneous
production by the speaker/writer or erroneous
reception by the listener/reader.
89- Figure 8.34
- Most students preferred Kool-Aid made with sugar
labeled sugar instead of sugar labeled not
cyanide, even though they had placed the labels
themselves. Evidently, people do not fully
believe the word not. (Based on results of
Rozin, Markwith, Ross, 1990)
90- Figure 8.35
- A student watches either a word or a single
letter flashed on a screen. An interfering
pattern is then flashed on the screen and the
student is asked, Which was presented C or J?
More students were able to identify the letter
correctly when it was part of a word.
91Human Specializations for Learning Language
- Reading
- Context is almost always important in
interpreting the parts of language - The word-superiority effect refers to the fact
that people are generally better at recognizing
individual letters when they are a part of a word
rather than when they are standing alone or with
a nonsense cluster.
92- Figure 8.36
- Students performed better at identifying an
indicated letter when they focused on an entire
word (a) than on a single letter in a designated
spot among random letters (b).
93- Figure 8.37
- According to one version of the connectionist
model, a visual stimulus activates certain letter
units, some more strongly than others. Those
letter units then activate a word unit, which in
turn strengthens the letter units that compose
it. For this reason we recognize a whole word
more easily than we recognize a single letter.
94Human Specializations for Learning Language
- How we move our eyes across a page or surface
while the parts of the words in part influence
reading - Phonemes are units of sound single letters or
combinations of letters. - Morphemes are units of meaning usually
syllables or words.
95- Figure 8.39
- The word shamelessness has nine phonemes (units
of sound) and three morphemes (units of meaning).
96CONCEPT CHECK
- How many phonemes comprise the word doggedly?
How many morphemes? -
It has five phonemes do-g-g-ed-ly. It has
three morphemes.
97Human Specializations for Learning Language
- Reading
- Human eyes move steadily when we are following a
moving object, but our eyes alternate between
brief stationary periods and periods of quick
movement when we are reading, which makes the eye
movements of reading rather jerky - Fixations are the periods when your eyes are
stationary. - Saccades are the quick eye movements that take
your gaze from one fixation point to another. You
are virtually blind during the saccades.
98Human Specializations for Learning Language
- Reading
- Why?
- The parietal cortex may signal the primary visual
cortex to shut down activity briefly during the
saccades. - Your brain may automatically direct you to attend
to the distinct stimulus at the end of each
saccade and ignore the blur that you sense during
each saccade.
99Human Specializations for Learning Language
- Reading
- We are seeing during the fixations and not during
the saccades. - This is all happening very, very quickly. Most
readers have four fixations per second, in
between which saccades occur lasting 25-50
milliseconds.
100Human Specializations for Learning Language
- Speedreaders
- Speedreaders have briefer fixations and backtrack
less frequently than do average adult readers. - With practice some people can double or triple
their reading speed with normal comprehension. - Some of the more extraordinary claims of
speedreaders remain untestable for example, the
claim that some can read between 5000 and 10,000
words per minute. - It is likely that these readers are fixating on
some words and guessing at the rest. - Speedreaders who know that they are going to be
tested on the details of what they have read are
observed to slow down substantially.
101Language
- It is still unclear why other species have not
evolved this incredibly useful skill of flexible
and productive language. - It is a large-scale adaptation of humankind that
has given us tremendous power in the natural
world.