Lecture 2 - Selective attention

Question 1

What is attention - William James?

Answer 1

• it is the taking possession by the mind, in clear and vivid form, of one of what seem several simultaneously possible objects or trains of thought
• focalization, concentration of consciousness are of its essence
• refers to both input and central processes

Question 2

Is attention a module?

Answer 2

• should think about an ‘attentional network’ of several different modules and processes that interact to guide behaviour

Question 3

Posner and Peterson 3 component model of the attention system?

Answer 3

1. alerting - a system that regulates arousal level to maintain optimal vigilance (central process)
2. orienting - the prioritisation of relevant sensory signals (input module)
3. executive - the conscious control of behaviour (central process)
   - the components can be double dissociated e.g.
   -> hemispatial neglect: neuropsychological condition with orienting problems with no executive or alerting deficit
   -> alien Hand syndrome: deficit of conscious control with no deficit of orienting or alerting
   - components have distinct cortical correlates

Question 4

What is the cocktail party effect - Cherry?

Answer 4

• ability to focus on 1 persons speech in a busy environment

Question 5

How can people attend to 1 person talking while ignoring other conversations?

Answer 5

• Cherry developed the shadowing paradigm (also called dichotic listening)
  -> Different word lists played to left and right ear
  -> Participant must repeat words from one ear
• Participants cannot recall words presented to unattended ear
  -> Fail to detect language changes or backwards words
• Attentional orienting acts like a filter that prevents information in the unattended channel being processed

Question 6

Broadbent’s filter theory?

Answer 6

• First information processing theory of attention
  -> Information about physical properties (e.g. tone, pitch, loudness) of stimuli are processed pre-attentively
  -> This information is used for channel selection: choosing which source of input to process
  -> Attended information is processed and acted on
  -> Information in the unattended channel is lost
• Selection by filtering = a specific kind of selection taken from Broadbent’s (1958) filter theory in which information is chosen from sensory memory on the basis of physical characteristics

Question 7

Evaluation of Broadbent’s filter theory?

Answer 7

• accounts for the findings of Cherry’s shadowing experiments
• but not all unattended information is lost
• there is a breakthrough from the unattended ear when:
  -> a word in the unattended ear makes sense in the context of the message in the attended ear
  -> the person’s name occurs in the unattended ear (Moray 1959)

Question 8

Attenuation theory - Tribesman & Geffen 1967?

Answer 8

• filtering is partial and not all-or-nothing as in Broadbent’s theory
• filter limits the amount of stimulus information that can be processed
• attended stimuli analysed in detail
• processing attenuated in unattended channel but not extinguished
• breakthrough occurs when:
  -> stimuli can be identified using limited information
  -> stimuli is consistent with ongoing tasks
  -> stimuli are very easily identified

Question 9

Spotlight metaphor?

Answer 9

• focuses on how we consciously process specific stimuli, much like a flashlight in a dark room
• explains why we can’t multitask effectively, as our attention shifts between tasks rather than covering them simultaneously

Question 10

What is overt attention?

Answer 10

• a movement of the eyes to fixate the spotlight attention on the location of interest

Question 11

What is covert attention?

Answer 11

orienting spotlight attention to a location that is not being fixated

Question 12

Spatial cueing task - Posner, Snyder & Davidson 1980?

Answer 12

• Fixate the centre of the screen and a cue orients attention to one or other side
• Participant must respond as quickly as possible to the appearance of the target
• 3 types of trial:
  1. Valid: Target appears at cued location
  2. Invalid: Target appears opposite cued location
  3. Neutral: Cue does not indicate any location

Question 13

Exogenous system for orienting spatial attention?

Answer 13

• involuntary, automatic
• stimulus driven
• fast
• inhibitory after effect

Question 14

Endogenous system for orienting spatial attention?

Answer 14

• voluntary
• goal-directed
• slow
• sustained

Question 15

Feature integration theory (FIT) - Tribesman & Gelade?

Answer 15

• integrates attention into information processing model of perception

Question 16

The binding problem?

Answer 16

• Visual processing splits objects into component features
• How does the visual system know which ones belong together?
• Triesman & Gelade (1980) explored this using visual search tasks

Question 17

Visual search tasks?

Answer 17

• have to find a target in a cluttered display
• 2 stages of processing:
  1. pre attentive = when objects are defined by single, salient features
  2. attentive = when features need to be combined
• attention acts like a ‘glue’ that binds features into objects

Question 18

Illusory conjunctions - Tribesman and Schmidt 1982?

Answer 18

• Participants identify numbers then identify shapes in briefly presented displays
• Participants incorrectly report letter/color combinations that are not present
• Triesman argues this shows attention needed to bind features into objects