Cognitive Psychology, 2nd Ed.

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Cognitive Psychology, 2nd Ed.

• Chapter 4

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Selective vs. Divided Attention

• Selective attention Process one stimulus while
  ignoring another.
• Divided attention Process both stimuli, by
  giving some attention to each.
• Shadowing Dichotic listening task where input
  from one ear is repeated aloud. Selective
  attention to the shadowed message results in the
  ignored message not being perceived and
  remembered.

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Filter Theories Early Selection

• Attentional filter operates after sensory
  processing but prior to meaningful semantic
  processing.
• Explains why ignored messages in shadowing task
  cant be rememberedthey were not semantically
  processed.
• Explains why sensory features of the ignored
  message (e.g., pitch) are processed and
  remembered.

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Filter Theories Attenuation

• Failures of selective attention occasionally
  occurfor example, noticing ones own name in the
  ignored message.
• An attenuation filter lowers the strength of the
  sensory signal in the ignored message, making it
  less likely to be perceived. Important
  stimulisuch as ones name pass through the
  filter without attentuation.

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Filter Theories Late Selection

• However, experiments showed even unimportant
  stimuli received semantic analysis. For example,
  semantic priming from a stimulus that backward
  masking deletes from conscious perception.
• Late selection filter occurs after sensory and
  semantic analysis but before response selection.

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Capacity Theories of Attention

• Depending on the task used, the filter seemed to
  be either early or late in processing. The
  ability to divide attention instead of
  selectively attend was also important to model.
• Capacity theories drop filters and assume
  attention is limited in overall capacity.
• Mental effort the proportion of available
  attentional capacity given to a task.

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Capacity Theories of Attention

• Single capacity Assumes attentional capacity is
  undifferentiated.
• Multiple resources Assumes there are multiple
  attentional capacities.
• auditory vs. visual perceptual modalities
• perceptual vs. cognitive resources
• vocal vs. manual response modalities

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Automatic Processes

• Stroop Effect Color names are printed in
  compatible or incompatible ink colors. Task is to
  name the ink color. Errors and response times
  increase for incompatible (RED printed in green
  ink) compared with compatible (RED printed in red
  ink).

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Automatic vs. Controlled Processes

• Automatic Processes
• unintentional
• unconsious
• effortless

• Controlled Processes
• intentional
• conscious
• effortful

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Visual Attention

• Visual attention is like a spotlight on the
  visual field. Brain circuits read out the
  contents of the spotlight, disengage it, and move
  it to a new location.
• Spatial Neglect A breakdown in visual attention
  whereby some areas of the visual field are not
  perceived.

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Executive Attention

• Attention given to manipulating and controlling
  mental representations and processes.
• Supervisory attentional system that inhibits
  inappropriate responses and activates appropriate
  ones.
• Anterior cingulate gyrus deep in the frontal lobe
  inhibits automatic responses in Stroop task, for
  example.

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Perceptual Binding

• Visual attention is needed for integrating
  stimulus features (e.g., color, shape, and
  location) in perception.
• Inattentional blindness and attentional blink
  illustrate failures to bind features in the
  absence of attention.

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Subliminal Perception

• Perception without attentionaccording to feature
  integration theory, unattended stimuli are
  unbound features and thus not perceived.
• However, individual features do register
• because of pre-attentive processing and can be
  measured on appropriate test.
• Familiarity and emotional preference also
  register from subliminal stimuli.