ATTENTION

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ATTENTION
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Attention

• Sternberg (1999) Attention acts as a means of
  focusing limited mental resources on the
  information and cognitive processes that are most
  salient at a given moment

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Attention

• Types of attention
• Vigilance
• Focused
• Auditory
• Visual
• Divided

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Vigilance

• Persons ability to attend to a field of
  stimulation over a prolonged period of time
  person seeks to detect the appearance of a
  particular target (Sternberg, 1999)
• A vigilance task usually involves waiting for
  something unpredictable to happen
• e.g. radar operator

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Vigilance

• Signal detection theory
• Technique which measures two components that
  affect the ability to detect signals
• Perceptual sensitivity to stimuli
  physiologically governed
• Decision criterion psychologically governed
  (variable) point at which you decide that youve
  detected a signal. Varies from conservative to
  reckless

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Focused Auditory Attention

• Illustrated by the cocktail party phenomenon
  (Cherry, 1953)
• Ability to listen selectively to one conversation
  during a party while ignoring the noise going on
  around you
• Questions what happens to the excluded
  message? To what extent is it processed?

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Focused Auditory Attention

• Dichotic listening task
• Different messages are presented to each of a
  participants ears
• S/he is asked to shadow or repeat one of the
  messages on-line
• Questions about the message in the unattended ear
• Only the physical characteristics of unattended
  message could be reported e.g. gender of voice
  (Cherry, 1953)

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Focused Auditory Attention

• Broadbents model (1958)
• An early selection model
• Sensory characteristics of all messages are
  processed
• A filter, under conscious control, selects one
  message
• Selection on the basis of physical
  characteristics, e.g. gender of voice
• All other messages excluded

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Focused Auditory Attention

• Broadbents Model (contd)
• But counter evidence suggests that the meaning of
  the unattended message, not just its physical
  characteristics, were being processed
• e.g. Moray (1959) you always detect your name
  in the excluded message
• e.g. Treisman (1964a) bilingual participants
  able to recognise the identity of two messages in
  different languages

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Focused Auditory Attention

• Treismans Model (1964)
• An early selection model
• All messages are processed beyond the sensory
  stage
• All messages are processed but unattended
  messages are attenuated
• Important stimuli (own name) have low thresholds
  so attenuated form is enough to activate name

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Focused Auditory Attention

• Deutsch Deutsch (1963)
• Response selection model
• All messages processed perceptually and for
  meaning. No filtering, no attenuation
• Bottleneck comes at the response stage, when only
  one of the messages can be responded to

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Focused Visual Attention

• Attentional shifts from one target to another can
  be achieved
• Overtly overt movement of head and/or eyes
• Covertly internal shift, in conditions where
  there is no time for eye movements

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Focused Visual Attention

• Analogies for covert attention
• The spotlight analogy
• Attention is like an internal spotlight. The area
  within the spotlight is attended to, the area
  outside is not
• The zoom lens analogy
• Experimental subjects can control whether they
  focus on a specific target (the middle letter of
  a five letter word) or spread their attention
  (across all the letters) (La Berge, 1983)

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Focused Visual Attention

• Treisman's feature integration model (Treisman
  Gelade, 1980)
• Describes the role of attention in perceptual
  processing
• Detecting the features (colour, size, corners,
  lines) of a stimulus is done in parallel
  (simultaneously) and needs no attention
• Integrating these features into a percept is done
  serially (one after the other) and needs attention

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Divided Attention

• Focused attention asks about the extent to which
  we can focus on one task and ignore others
• Divided attention asks about the extent to which
  we can do more than one task at the same time

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Divided Attention

• There is a general assumption of limited
  capacity
• i.e. resources available to process information
  are limited
• Two models
• Central resource theory a central bank of
  resources which is available for all tasks
  requiring mental effort
• Multiple resource theory several banks of
  specialised resources, e.g. specific to a modality

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Divided Attention

• Strategic Control the degree to which attention
  can be allocated, relatively, to competing tasks
  is under strategic control (Wickens Gopher,
  1977)
• Practice improves the ability to do simultaneous
  tasks because practice leads to automaticity
  (Anderson). Automatic tasks need very little
  attention

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Divided Attention

• Central vs. multiple resource theory
• Doing two similar tasks is harder than doing two
  dissimilar tasks
• e.g. Segal Fusella (1970) doing a visual
  imagery task with a visual detection task is
  harder than with an auditory detection task
• This suggests that there are separate resources
  for vision and audition, i.e. supports multiple
  resource theory