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Attention

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Title: Attention


1
Chapter 4
  • Attention

2
Multiple Meanings of Attention
  • Alertness or arousal
  • Orienting reflex or response
  • Spotlight attention and search
  • Selective attention
  • Mental resources / conscious processing
  • Supervisory attentional system

3
Two General Definitions of Attention
  • Attention as a mental process
  • The mental process of concentrating effort on a
    stimulus or a mental event.
  • Attention as a limited mental resource
  • The limited mental energy or resource that powers
    the mental system.

4
Input Attention -- Alertness and Arousal
  • The basic process of getting sensory information
    into the cognitive system.
  • Alertness and Arousal
  • A necessary precondition for cognition?
  • May not be needed for Implicit processing (e.g.
    Bonebakker Anesthesia study)

5
Cognition Without Attention (Bonnebakker et al.,
1996)
  • Gave a list of words during anesthesia
  • Gave an implicit memory test (word stem
    completion) after anesthesia
  • Exclude words that you remember
  • Showed some implicit memory for words heard while
    under anesthesia
  • ButImplicit memory is VERY limited

6
Input Attention -- Orienting
  • Reflexive attention / the orienting response
  • The redirection of attention toward an
    unexpected stimulus. (Largely Involuntary)
  • Habituation
  • A gradual reduction of the orienting response
    back to baseline.

7
Spotlight Attention and Search
  • The mental attention-focusing mechanism that
    prepares you to encode stimulus information.
    (Largely Voluntary)
  • Focus is Cognitive, independent of eye movement
  • Measured with the Spatial Cuing Task, and
  • the Visual Search Task.

8
Posners Spatial Cuing Task
9
PosnerSpatial Cueing Task RT
10
Posners Spatial cuing task
  • Benefit/Facilitation A faster-than-baseline
    response resulting from the useful advance
    information
  • Cost A response slower than baseline because of
    the misleading cue
  • Spotlight attention The mental
    attention-focusing mechanisms that prepares you
    to encode stimulus information.
  • Posner concluded from this and related
    experiments that the attentional focus subjects
    were switching was a thoroughly cognitive
    phenomenon it was not tied to eye movements or
    other overt behavior but to an internal focusing
    mechanism.

11
Visual Search -- look for bold T
12
  • R D
  • G
  • C T S
  • Q Z

13
  • L L L L L
  • L L L L L
  • L L L T L
  • L L L L L
  • L L L L L

14
  • F T F I T
  • W X W F E
  • T H F T W
  • I H T
  • T W X W
  • I A H T I

15
(No Transcript)
16
Explanation of Visual Search Results
  • One type of search is fast regardless of items.
    Parallel, automatic, easy.
  • One type of search takes longer with a larger
    of items. Serial, conscious, effortful,
    controlled.

17
Contrasting Input and Controlled Attention
(cont.)
  • Spotlight attention appears to be rapid,
    automatic, and perceptual. It is thereby
    distinguished from the slower, controlled or
    conscious attention process that matches the more
    ordinary connotation of the term attention.
  • Conscious or controlled attention prepares us to
    respond in a deliberate way to the environment.
    It is slower, operates in a more serial fashion,
    and is especially influenced by conceptually
    driven processes.

18
Controlled (Voluntary) Attention
  • A deliberate, voluntary allocation of mental
    effort or concentration.
  • Selective attention
  • The ability to attend to one source of
    information while ignoring other ongoing messages
    around us.

19
Controlled (Voluntary) Attention
20
Studying Selective Attention
  • The Cocktail Party Effect
  • Dual Task Procedures
  • Dichotic Listening / Shadowing Task

21
Two Models of Selective Attention
  • Broadbents Filter Theory.
  • Attention comes before pattern recognition.
  • Shortcomings?
  • Treismans Attenuation Theory
  • Pattern recognition comes before attention.
  • Treismans (1960) classic study

22
Broadbents Filter Theory
23
Treismans (1960) study
24
Normans Pertinence Model
  • Pertinence is the momentary importance of
    information, whether caused by permanent or
    transitory factors.

25
Normans Pertinence Model
26
Johnston and Heinz (1978)
  • Attention is flexible.
  • Selective attention can operate in multiple modes
    (early, middle, late).
  • But, later selection uses more of our limited
    attentional capacity.
  • So, later selection is slower and less accurate
    than middle or early selection.

27
The sequence of processes in the shadowing task,
with early, middle, and late operation of the
selective attention mechanism. (Adapted from
Johnston and Heinz 1978)
28
Results from Johnston and Heinzs research on the
multimode model of attention.
29
Attention as a Mental Resource
  • Kahneman (1973)
  • Attention is mental effort-- the mental resource
    that fuels cognitive activity.
  • Attention is limited-- only so much of the fuel
    can be devoted to mental tasks.
  • Also called controlled attention.
  • Contrast to automatic processes.

30
Automatic versus Conscious Processes
31
Automatic and Conscious Processing Theories
(cont.)
  • Posner and Schneiders three characteristics
    necessary for the diagnosis of an automatic
    process
  • The process occurs without intention, without a
    conscious decision
  • The mental process is not open to conscious
    awareness or introspection
  • The process consumes few if any conscious
    resources that is, it consumes little if any
    conscious attention.
  • Informal fourth criterion)The process operates
    very rapidly, usually with 1 s.

32
Automatic and Conscious Processing Theories
(cont.)
  • Conscious Processing
  • The process occurs only with intention, with a
    deliberate decision
  • The process is open to awareness and
    introspection
  • The process uses conscious resources that is, it
    drains the pool of conscious attentional capacity
  • (Informal fourth criterion)The process is slow,
    taking more than a second or two for completion.

33
The Stroop (1935) Task
  • Name the color of ink that each word appears in.
  • On Stroop trials, the words themselves identify
    colors (the word red printed in blue ink).
  • Word recognition is automatic, which interferes
    with color naming.

34
  • RED
  • BLUE
  • GREEN
  • YELLOW
  • RED
  • RED
  • GREEN
  • BLUE
  • BLUE

35
  • YELLOW
  • BLUE
  • GREEN
  • RED
  • YELLOW
  • RED
  • RED
  • GREEN
  • BLUE

36
Variations on the Stoop Task
  • Count the number of items on each line
  • aaa
  • bbbb
  • 2
  • 3333
  • 11
  • 44444
  • Is it left or right of center?
  • card /
  • / door
  • / book
  • right /
  • / left
  • right /

37
Practice and Automaticity
  • Practice can make a task more automatic.
  • Everyday Examples
  • Driving today (versus driving at age 16)
  • Reading today (versus reading at age 7)
  • Examples from Research
  • Spelke, Hirst and Neisser (1976)
  • Shiffrin and Schneider (1977)

38
Reaction times from Shiffrin and Schneiders
detection task
39
Percentage of correct detections of targets for
the same initial and after-reversal conditions
40
Disadvantages of Automaticity
  • Everyday Examples
  • Proofreading
  • Negative Transfer (In your new car, reaching for
    where the radio knob was on your old car).
  • Examples from Research
  • Barshi and Healy (1993)

41
Results of Barshi and Healys experiment, showing
the percentage of participants detecting the five
embedded errors in proofreading multiplication
problems. Problems were presented in fixed or
varied order. (Barshi and Healy 1993)
42
Hemineglect
  • Disruption or decreased ability to look at
    something in the (often) left field of vision and
    pay attention to it.
  • Research
  • Bisiach and Luzatti (1978)
  • -- Mental walk through the town plaza
  • Duncan et al. (1999)
  • -- can detect stimulus in damaged field, but only
    if no stimulus in un-damaged field. E.g.
    attentional processes are competing -- limited
    capacity?

43
Drawings copied by a patient with contralateral
neglect
44
Object-based neglect is demonstrated by the
copying performance of a patient with left
hemispatial neglect
45
Summary of Major Topics Covered in Chapter 4
  • Basic Input Attentional Processes
  • Controlled, Voluntary Attention
  • Attention as a Mental Resource
  • Disorders of Attention / Hemineglect
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