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					Cognitive Psychology




   Lecture 6: Attention

      October 2006
       Conor O’Malley
                What is attention?
• “concentration of mental activity” - Matlin 2005

• “the taking possession of the mind, in clear and vivid form,
  of one out of what seem several simultaneously possible
  objects or trains of thought. Focalisation, concentration, of
  consciousness are of its essence.” - William James 1890

• Mental spotlight
   – Focusing
   – Ignoring
                What is attention?
It serves as a strategy for dealing with the flood of
    information we are constantly receiving.
   – Does that mean it is a filter?
                What is attention?
It serves as a strategy for dealing with the flood of
    information we are constantly receiving.
   – Does that mean it is a filter?
              What is attention?
Traditionally research has distinguished between
  two forms of attention.

Focused attention: Participants are told to attend to one
  stimulus and ignore another. This informs us about the
  process of selection, and what happens to unattended
  stimuli.
Divided attention: Participants attend to all stimuli. This
  informs us about processing limitations and attentional
  capacity
What is attention?




       B
What is attention?




       D
What is attention?




       G
What is attention?




        J
What is attention?




       P
What is happening up here?




           S
What is happening up here?




           T
What is happening up here?




           Q
What is happening up here?




           M
What is happening up here?




           R
What is happening up here?


           W
                      X
What is attention?




       B
     Things to pay attention to!
We can pay attention outward or inward.
  – Can we know which is happening at a given time?


In experiments participants are often told what to
  attend to.
  – Is this anything like our real world experience?


Stimuli are often 2-d, computerised and weird
       Attention in the real world
“I have learned to cut out all unnecessary thoughts… on the
   track. I simply concentrate. I concentrate on the tangible -
   on the track, on the race, on the blocks, on the things I
   have to do. The crows fades away and the other athletes
   disappear and now its just me and this one lane”
   Michael Johnson
  Olympic Gold Medalist 2000
       Attention in the real world
“That was the best golf I have ever played. I was in my own
  little world, focusing on every shot. I wasn’t thinking what
  score I was on or anything…”
                             Darren Clarke, 1999, having shot
                             a 60 in the European Open
    Focused Auditory Attention
It is possible to hear many conversations, but only listen to
one. We can distinguish the conversation we are interested
in from the rest of the auditory environment by picking up
on a number of features:

     • Speaker’s voice

     • Speaker’s location

     • Content of speech
  Focused Auditory Attention
Cherry (1953) and Moray (1959) carried out dichotomous
listening tasks in which participants had to shadow the
speech heard by one ear.

  – Listeners seldom noticed if unattended ear contained foreign
    language or reversed speech

  – Listeners always noticed when speech changed to pure tone

  – Listeners seldom remembered content of unattended speech
    even if it was a word repeated 35 times

  – Unattended ear receives practically no processing
  Focused Auditory Attention
Broadbent’s theory:
Reported findings where three digits were presented to
one ear, and a different three were presented to the other.
• Participants chose to recall digits by ear rather than by
pair
             Broadbent’s Theory
He accounted for these and other findings in the
 following way
• Two sources on info gain access in parallel to sensory
  buffer (this implies the info can linger here)

• One input is allowed through a filter based on its basic
  characteristics, while the other remains on the buffer for
  later processing

• Beyond the filter a mechanism processes the info
  thoroughly (meaning etc.)
              Broadbent’s Theory
• Explained experimental findings well

• Assumed wrongly that the unattended message is always
  rejected.
   – People with practice at shadowing were shown to process up to
     67% of unattended info (Underwood, 1974)


• Did not consider presenting inputs in different modalities.

• Wright, Anderson & Stenman (1975) showed processing for
  unattended words. They conditioned participants to
  associate some words with mild shock.
              Broadbent’s Theory
System is inflexible:

Gray & Wedderburn (1960)
            Treisman’s Findings
• Reported findings that the unattended words were
  sometimes recalled

• Known as ‘breakthrough’

• Occurs when the word in the unattended channel is highly
  relevant to the content of the attended input
               Treisman’s Theory
Stimulus analysis proceeds through a hierarchy beginning with
   physical attributes, and ending with semantic processing.

If there is insufficient processing capacity, then analysis stops
    before reaching the end of the hierarchy.

There is a threshold of consciousness that partially processed
  stimuli can exceed. So unattended words may
  ‘breakthrough’

Deutsch & Deutsch (1963) argue that both inputs are
  processed fully
 Focused Aud. Attention Theories
All theories propose that somewhere there is a bottleneck
   which allows some info through and slows down the rest.

The main difference between these theories is the location of
  the bottleneck.

Broadbent argues that bottleneck occurs early in the system,
Triesman argues that bottleneck occurs mid-way in the system,
Deutsch & Deutsch argue that bottleneck occurs late in the
   system.
         Perceptual Load Theory
Lavie (2000)

• Everyone has limited attentional capacity

• The amount allocated to main task depends on its
  perceptual load (number of units, type of processing)

• Any spare capacity is automatically given to the unattended
  input
         Perceptual Load Theory
Lavie (2000)

• This leads to the conclusion that there will be an early
  bottleneck when perceptual load is high

• And that there will be a late bottleneck when perceptual load
  is low
          Perceptual Load Theory
Lavie (1995): Participants had to detect either ‘x’ or ‘z’

Low load:      ___x_

High load:    artxc

Large distractor letter also appeared. Either a ‘z’ or ‘s’.

The nature of this letter should have a relatively bigger effect
  on reaction time in the low load condition
         Perceptual Load Theory

The exact nature of ‘perceptual load’ is somewhat vague.

Can we measure it?
         Focused Visual Attention
Studied extensively from a cognitive neuropsychological
  perspective.

Disorders of visual attention:

                            Neglect

                            Extinction

                            Balint’s Syndrome
                          Neglect
Results in one half of the visual field being ignored

The ignored side is contra-lateral to the brain insult

The person is capable of seeing things to the neglected side if
  they shift their head position to bring the item to the other
  side of the visual field
                        Neglect
Results from damage to the right parietal lobe
                         Neglect
Results from damage to the right parietal lobe

Neglect patients fail to notice or respond to objects presented
  on the left side
                         Extinction
A single stimulus can be judged normally

When two stimuli are presented, one goes undetected

The one that is undetected is on the side contra-lateral to the
  brain damage.

                     x
                         Extinction
A single stimulus can be judged normally

When two stimuli are presented, one goes undetected

The one that is undetected is on the side contra-lateral to the
  brain damage.

                     x                    x
               Balint’s Syndrome
Results from lesions to posterior parietal lobe, or at the parieto-
  occipital junction

Symptoms:
                     fixed gaze
                     gross mis-reaching for objects
                     simultagnosia (only perceiving one item)
              Attentional Systems
There is often a distinction made between

• Goal directed attention
   – Influenced by expectation, knowledge & current goals




• Stimulus driven attention
   – Unexpected occurrences that grab attention
             Attentional Systems
There is often a distinction made between

• Goal directed attention




• Stimulus driven attention
        Focused Visual Attention
Location Based Attention:

             It is like a spotlight illuminating an area
             This area can be narrowed if the task demands it



Object Based Attention:

             Attention is directed to objects rather than to an
             area
         Location Based Attention
Posner (1980) discussed covert attention. Attention can shift
  in the absence of eye movements.

Participants fixated on central point and had to identify a light to
  the left or right.

Central point could be a neutral cross, or a direction arrow

                             
                             
                             
        Location Based Attention
Posner (1980)
      Valid arrows reduced reaction times from control (cross)

      Deceptive arrows increased reaction times from control

      These happened in the absence of eye movements
        Location Based Attention
St James (1986)
      Participants had to answer about a target stimulus
      who’s location was indicated beforehand

      A distractor caused interference

      The area over which interference effects were found
      was less when the participants had longer forewarning
      of the target stimulus

      Evidence that visual attention zoomed in
Location Based Attention (Limitations)
Evidence that attention can be split between two non-adjacent
  regions of space



Attention can be directed to objects as opposed to areas



Zoomed attention implies little processing of unattended area.
  Evidence that this is not always the case
          Object Based Attention
O’Craven et al. (1999)
      Two objects appeared superimposed onto eachother
  (face & house)
      One moved slightly and participants had to attend to
  either moving or stationary objects
      fMRI scan showed that face area ‘lit up’ when face was
  being attended to and house area ‘lit up’ when house was
  being attended to.

Face area = Fusiform face area
House area = Parahippocampal place area
          Object Based Attention
Marshall & Halligan (1994) Neglect Patient Study
     Ambiguous shape was seen as either
                    black object with white background
     or
                    white object with black background

They could draw the separating line when asked to draw the
  left side of the picture, but not when asked to draw the right
  (neglected) side.

Seen as evidence of object based attention

Other evidence from plant drawings
          Object Based Attention
It is clear that object based attention is present in humans, but
    this view fails to explain the findings that show location
    based attention.

Are the studies ecologically valid???
             Crossmodal Effects
In our everyday negotiation of the world we use cues from one
   sensory modality to direct the attention of the other

  Crossing a road: Our ears are drawn by the sound of a car
                   and this then directs our visual attention

In the laboratory, Driver & Spence (1998) used tactile
   stimulation to improve visual judgement. The tactile cues
   drew covert visual attention as the person’s eyes remained
   fixated on the central cross
            Crossmodal Effects
A more spectacular example!
             Crossmodal Effects




The ventriloquist effect happens when we perceive a sound
  as coming from the most obvious visual source. It is also
  know as visual capture
     Crossmodal Effects
           

                


                        
             Crossmodal Effects
Visual capture usually occurs when there is incongruity
  between vision and audition. We are predominantly visual
  creatures.

This normally has to do with location. (Think of the cinema)

Auditory capture can happen. This normally occurs in relation
  to temporal features.

If a light flashes at one rate and a sound beeps at another, we
    perceive the light to be flashing at the auditory rate
Divided Attention
               Divided Attention
Easy for some things:
            Driving and talking

Hard for other things:
              Patting head and rubbing stomach
Factors effecting dual task performance
Task similarity:
  Easy to do things which are dissimilar (drive & talk).

  We recall unattended pictures when shadowing an auditory
  stream.

  If we have to do different things with items in the same
  modality it is difficult
Factors effecting dual task performance
Practice:
  Spelke et al. (1976) trained people to read and understand
  short passages, while writing down words from dictation.

  The performance of participants improved hugely over 6
  weeks of training

  “People’s ability to develop skills in specialised situations is
  so great that it may never be possible to define general limits
  on cognitive capacity”
Factors effecting dual task performance
Task Difficulty

       Easier to drive and chat, than drive and conduct a job
       interview

       This is obvious, but how do we define task
       difficulty
             Automatic Processing
The practice effects shown in Spelke et al. (1976) prompted
  speculation as to how we can become so good at difficult
  tasks

The common explanation is that some processing becomes
  automatic.
             Automatic Processing
Automatic processes do not tax attention

• They are fast

• They do not reduce capacity for performing other tasks

• They are unavailable to consciousness

• They can be unavoidable
            Automatic Processing
The Stroop Effect
Automatic Processing
             Some relevant research
Ciarán McMahon. PhD Candidate at UCD
“The History of the Modern Psychological Concept of Attention”

Greek notion of Prosoché denoted a spiritual attitude and approach
  to life, to be maintained constantly throughout the waking hours

After fall of Roman empire, prosoché becomes associated with
   reading scripture

Augustine (4th century) uses attentio in an internal sense; part of a
  mental and spiritual presence of mind

Thomas Aquinas (1272) refers to attention in prayer, acknowledging
  that in may be absent from a person’s internal dialogue
             Some relevant research
Around the time of Shakespeare there was established the
  assumption that words used to describe subjective experience can
  be accurately transposed to objective situations (i.e. is my
  'attention' the same as your 'attention'?)

It is later in 17th century that the notion of ‘losing attention’ emerges

Later the notions of attention and consciousness are debated
            Some relevant research
“It is impossible to define the term or describe the concept
    without betraying one’s own social and discursive context,
    except perhaps to report its basic etymology of tension
    between subject and object; none of which should, however,
    detract from its authenticity as a viable topic of psychological
    investigation.”

       ciaran.mac.mathghamhna@gmail.com
                          Reading
Eysenck & Keane: Chapter 5


Article:
Rushworth, M. Paus, T. & Sipila, P. (2001) Attentional Systems and
  the Organization of the Human Parietal Cortex. The Journal of
  Neuroscience, 21 (14); 5262-5271
                          Reading
Article:
Rushworth, M. Paus, T. & Sipila, P. (2001) Attentional Systems and
  the Organization of the Human Parietal Cortex. The Journal of
  Neuroscience, 21 (14); 5262-5271

Presentations should include

• Summary of experimental method
• Major findings
• Usefulness of findings
                            Exam
Course divided into 8 topics:

Memory
Mental Imagery
Attention
Reasoning
Problem Solving
Language
Consciousness
Knowledge

Exam will take the format of 6 questions, choose 3

				
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