Please enable JavaScript.

Coggle requires JavaScript to display documents.

Attention & Social Attention (Social attention (Friesen and Kingston…

- - - - Fixation (engagement) inhibits movement
      - Alerting - decision to shift attention to a new spatial location
      - Disengage - Move – Engage
      - Three fundamental propositions
        
        The attentional system is separate from the ‘data processing’ system (but interacts with other systems)
        
        Attention is carried out by a network of anatomical areas
        
        These areas carry out different functions that can be specified in cognitive terms
        
        Three major functions
        
        Detecting stimuli (for conscious processing)
        
        Anterior (frontal) Attention system
        
        For focal and conscious processing – (Executive functions
        
        Lateral and medial frontal cortex • Anterior cingulate
        
        Detecting an event leads to disrupted processing of other events E.g. monitoring auditory message impairs orienting to visual cues (separate but interacting systems)
        
        Maintaining a vigilant or alert state
        
        Right Hemisphere (Norepinephrine system)
        
        Right hemisphere anterior cingulate, medial-frontal, dorsolateral frontal system
        
        Orienting to sensory events
        
        Posterior Attention system
        
        Covertly attending to a location improves, detection of events at that location
        
        Posterior parietal lobe – Damage – unilateral neglect
        
        Pulvinar (part thalamus) – Spatial localisation and feature binding – Damage – deficit in detecting threat – Connection with amygdala
        
        Superior colliculus – Role in shifting attention
      - Attentional system: 20 years after Petersen and Posner (2012
        
        Orienting
        
        (i) Dorsal system – shifts of attention (parietal IPS and frontal-eye fields FEF
        
        (ii) Ventral system – respond to external salient events Temporoparietal & ventral frontal regions
        
        Executive Control (Detection)
        
        Two Networks – Frontoparietal – relating to implementing task instructions
        
        Cingulate (ACC) /opercularis – ‘task-set’ change of plan, error monitoring
        
        Alerting / Vigilance
        
        Norepinephrine (NE) system Warning signal – increases activity in locus coeruleus produces NE
        
        Both right and left hemispheres may have a role (tonic / phasic alerting)
  - - - A spotlight with a fixed capacity, but can vary in size
      - Method: Five letter words 1. Categorise (attend to) the central letter 2. Categorise (attend to) the whole word 3. Response to a‘probe’(target) 7 at any spatial position
      - Results
        
        Reaction time (RT) - ‘V’ shaped function in letter task
        
        Flat RT function for whole word task
        
        Attention can be narrowly focused or widely distributed
    - - Target always appeared in cued box (100% valid cue)
      - Neutral - 50:50% cued/uncued
      - Attention cued to large, medium, or small marker boxes
      - A variation on Posner’s cueing experiment
      - RT’s influenced by size of cued area (box size):
      - Small = 285 ms Medium = 301ms Large = 314 ms
      - Small focus of attention - more efficient
- - - - degree of dependence bwteen eye movements and spatial attention ranges from complete to independent with efference theory and functional relation inbetween
  - - - If covert and overt attention are not independent then:
        
        Attending covertly to a location should speed up overt shifts of eye movements to that location
        
        Attending overtly (by preparing eye movement) should facilitate perception at that location
        
        Klein (1980) tested these hypothesis
        
        Oculomotor readiness hypothesis OMRH
        
        Dual task: make a saccade and manual response to detect brightening of target (‘probe trials’)
        
        Dual task performance: • Preparing a saccade reduces saccade RT
        
        Always prepare a saccade to one of 2 targets (left or right)
        
        Preparing a saccade did not influence manual RT
        
        So – covert and overt systems are independent But other evidence supports a link
    - - Covert first then overt eye movement follows
      - A functional relationship between covert and overt attention
        
        Four assumptions of the model:
        
        – At the beginning of a fixation covert attention is allocated at fixation
        
        – After identification, covert attention is then allocated to a new location
        
        – Saccade programming to the new location starts, once covert attention shifts
        
        – Higher level processing can then start at the new location
        
        Covert and Overt attention are ‘yoked’
        
        Covert attention can only be in one place at a time
        
        Only one saccade can be programmed at a time
      - Evidence
        
        Parafoveal processing benefits
        
        During reading: When reading - some information about the next word (word n+1) is obtained during fixation (of word n) e.g. Word skipping behaviour (of high-frequency short words – ‘and’, ‘the’)
        
        Preview effects during object scanning Scanning objects in fixed order – time spent fixating each object is reduced when all four presented together
    - - Shifts of attention are generated by same neural system used to plan and execute actions (e.g. eyes and reaching
      - .A single system produces covert AND overt movements
        
        Two pieces of evidence that support this view: •
        
        ‘Meridian crossing effect’ (in Posner task)
        
        RT’s faster at cued location, slower non-cued
        
        Small ‘valid’ benefit (-6 ms)
        
        Small cost invalid target in same direc%on (+8 ms)
        
        Large cost invalid target in opposite direc%on (+33-48 ms)
        
        = ‘Meridian crossing effect’
        
        Saccade trajectory effects and evidence for the overlap of brain areas involved in both
        
        Brain areas involved in control of eye movements overlap with a"en%onal areas
        
        Corbe"a and Shulman (2002)
        
        Meta-analysis brainimaging studies
        
        Covert orien%ng of a"en%on involves the prepara%on of an eye movement to that loca%on – • – –
        
        Meridian crossing effect reflects the addi%onal cost of a change in direc%on
        
        (cancel leNward eye movement, programme new rightward movement)
        
        So, covert spa%al a"en%on effects reflects underlying programming in the eye movement (saccadic system)
        
        Further evidence- curved saccade trajectories