PSY 190: GENERAL PSYCHOLOGY CHAPTER 8: COGNITION

PSY 190: GENERAL PSYCHOLOGY

CHAPTER 8:COGNITION

How important is attention?

1987 Northwest Airlines jet from Detroit crashed moments after take-off 154 passengers and crew, 2 on ground,

died

Attention

Close or careful observation or mental concentration

A selective narrowing or focusing of consciousness

Different Aspects of Attention

Selective Attention Visual Auditory

Selective Attention

Focusing our awareness on only part of everything we are experiencing Trying to attend to one task over another

Selective Attention: Visual

The Stroop Test (1935) Names of words

cause a competing response Flanker

compatibility task

Task–irrelevant stimuli are extremely powerful

Dalrymple-Alford & Budayr (1966): First to encourage presentation & timing of stimuli individually. This method now dominates.

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Congruent Incongruent

Tim

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BLUEGREEN

Stroop

effect

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Congruent Incongruent Control

time

(ms)

BLUEGREEN

interference

facilitation

Selective Attention

Neisser et al. (1979)In this one minute video,

there will be two basketball teams You task is to count the passes of just one team

Click on picture for video

Selective Attention

Simons & Chabris (1999)

Click on picture for video

Attention & Visual Perception

Mack & Rock (2000)Research on a phenomenon known as inattentional blindness suggests that unless we pay close attention, we can miss even the most conspicuous events

Sights unseen?

Inattentional Blindness Participants were asked

to focus on a cross They often failed to

notice an unexpected object, even when it had appeared in the center of their field of vision

Mack & Rock (2000)

Change Blindness

People fail to detect substantial features of photographs and real world experiences

They seem to lack a precise visual representation of their world from one view to the next

Daniel Simons

Levin & Simons study (1997)

Levin & Simons study (1998)

Click on pictures below for videos

Choice Blindness

Johansson, Hall, Sikstrom, & Olsson (2005)Participants failure to detect a mismatch from their original choice to what was later presented to them as their original choice (but was not)

Petter Johansson

Click on pictures above for videos

Selective Attention (Auditory)

Dichotic listening task (Cherry, 1953) Any task where two streams of auditory

information are presented simultaneously, one to each ear (generally over headphones). Subjects are required to attend to one ear only.

Shadowing task -- Two messages played, one to each ear. One message has to be "shadowed" by the subject (repeated back out loud). This is called the “attended” message.

In Shadowing Task…

Listeners seldom noticed the unattended message being in a foreign language or in reversed speech However, they nearly always noticed physical

changes in the unattended messageCherry’s conclusion? 

People can shadow accurately but its not easy 

Unattended auditory information receives very little processing

Categorization

Categorization Process by which things are placed into groups

Concept Mental groupings of similar objects, events, ideas, and

people

Knowing about something is in a category gives us a great deal of information about it.

Knowledge Can Affect Categorization

Knowledge of the world informs and shapes our predictions about concepts

Features in a complex network of explanatory links indicate Relative importance of features Relations among features

Objects classified into concept that best explains the pattern of attributes

Do we categorize males as being more angry?

Becker et al. (2007) Used gender-neutral faces in attempts to determine

this Categorization Heuristics

Categorization can lead to errors in stereotyping…

Here’s another error…

Problem Solving

Mental processes that occur when people work toward determining the solution to a problem

Kahneman (2011) Two systems appear to be involved

System 1 – used for automatic processing

System 2 – used for effortful processing

Availability HeuristicsWe use our memory of actual instances for

our judgment. So, when we make a judgment, things that are available in our mind determine our judgment.

Example Think of words that begin with r. Think of words that have r in the third

position? Which is easier to think of?

The availability heuristic: We base our judgments of the frequency of events on what comes to mind

There are three times as many words with r in the third position (car, park, barren, march)

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What’s going on?

Which cause of death is more likely?

Homicide or AppendicitisAuto-train collision orDrowning

Measles or SmallpoxBotulism or AsthmaAsthma or TornadoAppendicitis or Pregnancy

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Lichtenstein et al. (1978)

Actual correlations: It’s cloudy and there’s a smell in the air, so it will probably rain

Illusory correlations: We think things are correlated, but they are not One group and their stereotype

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Availability: Illusory Correlations

Making judgments based on outward appearances only even though the base rate is low

One person represents the larger group Extrapolate behavior of one person to everyone else

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The Representativeness Heuristic

The Representativeness Heuristic

Tversky & Kahneman (1974) These researchers presented this example:

We randomly pick one male from the population of the US. He wears glasses, speaks quietly, and reads a lot. Is it more likely that this male is a librarian or a construction worker?

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Amos Tversky Daniel Kahneman

Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with the issues of discrimination and social justice. Which of the following is more probable?

Linda is a bank teller.Linda is a bank teller and is active in the

feminist movement.

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The feminist bank teller

Tversky & Kahneman (1983)

A certain town has two hospitals. The large hospital has ~45 babies born a day, and the small hospital has ~15 births a day. About 50% of all babies are boys. However, the exact percentage varies by day. For a period of 1 year, each hospital recorded the days on which more than 60% of babies born were boys. Which hospital recorded more of these days?

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The problem of small samples

Tversky & Kahneman (1974)

We have a tendency to selectively look for information that conforms to our hypothesis and to overlook information that argues against it.

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The Confirmation Bias

The way a question is worded can influence how people answer a question

How choices are stated seems to matter When a problem is framed in terms of gain,

we tend to choose sure things (risk-aversion strategy).

When a problem is framed in terms of loss, we tend to choose risky things (risk-taking strategy)

Framing Effect36

Framing Effect

Example:If you are lucky, you have a chance to win $1000. Which game do you choose? Game A. a sure gain of $240 Game B. 25% chance to gain $1000 and 75%

chance to gain nothing

Game A 84% Game B 16%

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Framing Effect

Example:You are given $1000, provided that you will play either one of the following games. Which game do you choose?

Game C. a sure loss of $750Game D. 75% chance to lose $1000 and 25% chance

to lose nothing.

Game C. 13%Game D. 87%

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Framing Effect

Sunk Cost EffectThe willingness to do something because

of money or effort already spentThis is a special case of the framing effect

What Is Expert Cognition?

What makes someone an expert at anything?

What Is Expert Cognition?

Reber (1967) Implicit learning

Learning that appears to occur without awareness or intention to learn and often cannot be described in words what has been learned

“Cognitive unconscious”

Implicit Learning: Learning that lacks perception?

Reber (1980)Too many variables involved – too much to

remember In explicit learning, we consciously

select only the key variables In implicit learning, we are unselective

and pay attention to all variablesFew attentional resources are needed

Implicit Learning: Expert Knowledge?

McGeorge & Burton (1990) Implicit learning allows us to skip steps Everything becomes automatic We become experts

Implicit Learning: Expert Knowledge?

Examples: Chess players Football QB’s Riding a bike

Practice Makes (Nearly) Perfect

Practice is crucial Motivation is crucialExpertise can sometimes overcome effects

of age, but response time slower

Expert Pattern Recognition•Chase & Simon (1973)• Chess master vs. beginners• Memorize chess pieces positioned for a real chess game for 5 seconds• Reproduce the arrangement shortly after

Expert Pattern Recognition

Procedure Participants were

given five seconds to memorize board

They were then asked to draw an empty chess board and reproduce the arrangement of pieces

Chase & Simon (1973)

Actual Game Random Game

Chase & Simon (1973)

(a) The chess master is better at reproducing actual game positions

(b) Master’s performance drops to level of beginner when pieces are arranged randomly

Chase & Simon (1973)

Chunking Helps• Chase & Simon (1973)• Implication: Chess master did not have a superior STM (as some had suggested); rather he had stored many of the patterns that occur in real chess games in LTM

• He saw the layout of chess pieces not in terms of individual pieces but in terms of 4-6 chunks, each made up of a group of pieces that formed familiar, meaningful patterns

• The chess master’s advantage vanished when the board was arranged randomly – familiar patterns were destroyed

Credits

Some slides prepared with the help of the following websites:www.whizzesworld.net/Psychology/PPT/.../attention-and-cons...

http://www.scribd.com/doc/83755755/8/Change-Detectionwww.atkinson.yorku.ca/~park/memory/lec2.pptwww.itu.dk/.../2011-Spring-HIP-Lecture09-...www.tamu.edu/faculty/takashi/.../Ch%209%20Knowledge.ppt