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Cognition, 8e
Chapter 3
Perceptual Processes II:
Attention and
Consciousness
Cognition, 8e by Margaret W. Matlin
Chapter 3
Chapter Introduction
• Trying to attend to everything at once is
more than the cognitive processes can
handle.
• attention—concentration of mental
activity
• top-down and bottom-up processing
• attention and visual phenomena
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Divided Attention
divided-attention task
• trying to pay attention to two or more
simultaneous messages
• respond appropriately to each message
• speed and accuracy suffer
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Divided Attention
multitasking
• walking and talking
• reading and IM
• People may believe that they can
multitask, but the research does not
support this illusion.
• People perform faster and more
accurately if they work on one task at a
time.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Divided Attention
driving studies
Collet and coauthors (2011)
• handheld cell phone while driving
• reaction times during driving are 20% slower than without
the cell phone
Strayer and colleagues (2003)
• hands-free cell phones, traffic
• slower to brake
• inattentional blindness
passenger conversations
task switching
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Selective Attention Overview
• pay attention to certain kinds of
information, while ignoring other ongoing
information
• simplifies our lives
• People notice little about the irrelevant
tasks.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Dichotic Listening
• a selective-attention task
• one message presented to left ear and a
different message presented to right ear
• shadow one of the messages
• People notice very little about the
unattended message.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Dichotic Listening
In general, people can process only one
message at a time. However, people may
process the unattended message when:
1. both messages are presented slowly
2. the task is not challenging
3. the meaning of the unattended message is
immediately relevant
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Dichotic Listening
cocktail party effect
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
The Stroop Effect
a selective-attention task
Demonstration 3.1: The Stroop Effect
• naming the ink color of words
• incongruent words vs. colored patches
• People take a long time to name the ink
color when that color is used in printing an
incongruent word; in contrast, they can
quickly name that same ink color when it
appears as a solid patch of color.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Demonstration 3.1: The Stroop Effect, Part A
Say out loud the names of the ink colors, ignoring the
meaning of the words. Measure the amount of time it takes
to go through this list five times. Record that time.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
The Stroop Effect
explanations in terms of PDP and practice
reading as automatic process
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Visual Search
• a selective-attention task
• find a target in a visual display with
numerous distractors
Variables Influencing Visual Search
more accurate if the target appears frequently
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Visual Search
Variables Influencing Visual Search
Treisman studies
1. The isolated-feature/combined-feature
effect.
Demonstration 3.2: Treisman and Gelade (1980)
searching for blue Xs
Cognition, 8e by Margaret W. Matlin
Chapter 3
Demonstration 3.2 Part A
First, look at the two figures below. In each case, search
for a blue X. Notice whether you take about the same
amount of time on these two tasks.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Demonstration 3.2 Part B
Look for the blue X in each of the two figures below. Notice
whether you take the same amount of time on these two
tasks or whether one takes slightly longer.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Visual Search
Variables Influencing Visual Search
Treisman studies
1. The isolated-feature/combined-feature
effect. (continued)
If the target differed from the irrelevant items in the
display with respect to a simple feature such as
color, observers could quickly detect the target.
When the irrelevant items force you to search for a
combination of features (both blue and X), visual
search takes longer.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Visual Search
Variables Influencing Visual Search
Treisman studies
2. The feature-present/feature-absent effect.
Demonstration 3.3: Treisman and Souther (1985)
searching for "circle with the line" or "circle without
the line"
People can typically locate a feature that is present
more quickly than a feature that is absent.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
Visual Search
Variables Influencing Visual Search
Royden and colleagues (2001)
People can quickly locate one moving target when
it appears in a group of stationary distractors.
In contrast, they take much longer to locate one
stationary target when it appears in a group of
moving distractors.
It’s easier to spot a movement-present object than
a movement-absent object.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
In Depth: Saccadic Eye Movements
During Reading
• a selective-attention task
• eye movements important in looking,
searching, driving, speaking, and
reading
saccadic eye movement
• series of little jumps of the eye
• bring the center of the retina (fovea) over
the words being read
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
In Depth: Saccadic Eye Movements
During Reading
fixation
perceptual span
patterns—The eye usually moves past
blank spaces, short words, and highly
predictable words, but the eye usually
pauses for misspellings, unusual words.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Several Kinds of
Attention Processes
In Depth: Saccadic Eye Movements
During Reading
good readers vs. poor readers—size of
saccadic movements, regressions, pauses
Cognition, 8e by Margaret W. Matlin
Chapter 3
Explanations for
Attention
Theories of Attention
Early Theories of Attention
Bottleneck theories
• narrow passageway
• information either passes through
bottleneck or is lost
• too simple; underestimate flexibility
• information not lost at just one phase of the
attention process
Cognition, 8e by Margaret W. Matlin
Chapter 3
Explanations for
Attention
Theories of Attention
Feature-Integration Theory (Anne
Treisman)
1. The basic elements
distributed attention
focused attention
register features automatically
slower serial processing
parallel processing
identify one object at a time
identify features simultaneously
complex objects
low-level processing
identify which features belong
together
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
Three Interrelated Issues
1. our inability to bring certain thoughts into
consciousness
2. our inability to let certain thoughts
escape from consciousness
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
Consciousness of our higher mental
processes
• mindless reading
• mind wandering
Nisbett & Wilson (1977)
little direct access to our thought processes
products vs. processes
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
People have relatively complete access to
some thought processes, but only limited
access to other thought processes.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
Thought Suppression
thought suppression—the attempt to
eliminate thoughts, ideas, and images
related to an undesirable stimulus
Demonstration 3.5: Do not think about a
white bear!
ironic effects of mental control
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
Blindsight
vision without awareness
damage to visual cortex
can still identify some visual attributes of
stimulus reported as "not seen" (no
conscious awareness of object)
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
Blindsight
Possible explanation
• A small portion of the information from the
retina travels to other locations on the
cerebral cortex, outside the visual cortex
• Some characteristics of the visual stimulus
may be identified by information registered
in other cortical locations.
Cognition, 8e by Margaret W. Matlin
Chapter 3
Consciousness
Blindsight
Possible explanation (continued)
• Primary visual cortex is necessary for
conscious awareness of visual information.
• Perception of the stimulus (without
conscious awareness) may be possible.
Cognition, 8e by Margaret W. Matlin
Chapter 3

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