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Task 4 Consciousness :3 !! attention and stuff :3 !! (Phenomena (blindness…

- - - - Posner task
        ---> they fixate of middle of screen,
        ---> cue will appear for a few secs, indication on which side of screen the "actual stimulus "will appear 500ms later (important distinction to exogenous attetnion) (
        --> 75% of time it will appear there but 25%of the time it doesn't (participants don't know this though)
        --> if cue predicts and stimulus actually appears reaction time quicker than neutral condition (no cue given)
        --> if cue predicts one side but then stimulus is shown on other side reaction time much higher than neutral condition and even higher than if cue correctly predicted it
        ---> shows upside and downside of top down processing :3 !!
    - - Posner task
        --> difference is that the cue is followed by the actual stimulus almost immediately after just 100ms !
        --> this guarantees that changes in reaction time is because the cue grabbed and shifted the attention of the viewer automatically
        ------> in the posner task the stimulus follows the cue 500ms later, which guarantees that the participant had enough time to recover from the involuntary attention grab of the cue and only reacts to the actual direction of the cue :3 !! #
        --> cue predicts stimulus 50% of the time (can be 50/50 here cause involuntary attention, if like above dependent on direction the cue is fcing they would ignore the cue if it would be a complete random 50/50 chance because fo rthem they would figure out it woul dpredict nothing :3!!
    - - covert
        --> change in attention without making eyemovemnts
        --> so the change in attention is not observable by looking at your eyes (overt) :3 !!
      - overt
        --> change in attention is accompanied by eye movemnt
        ---> in other words the change in attention is visible / (OBSERVable) because you saw the eyes move :3 !!
    - - Egly’s object attention experiment
        --> Two vertical bars equally far apart
        --> A "Cue" is presented at the top of left vertical bar, (if stimulus follows on same location then = valid)
        ---> now if stimulus follows invalidly on the bottom of the same vertical bar = reaction time = slower
        --> BUT if stimulus follows invalidly on the top of the right vertical bar, the reaction time is even slower then as if presented on the same (left) vertical bar EVEN THOUGH they are equally far appart spaced from the cue stimulus
        --------> this shows there is object attention as reaction time is quicker when "stimulus" is invalidly displayed on the same object (left vertical bar) rather than on another object (right vertical bar) even though they are equally far spaced apart :3 !!
        
        ----> but might it not just be because of different locations ? .. --> check the paper to see if they also checked for the bottom part of the right vertical bar!! (cause thats the same location then as the bottom of the left vertical bar) only then really that can be said to be true cause else it might just be the difference of location on the object (upper part vs lower part) that is causing these results :3 !!
    - - time task
        --> cue was given whether stimulus would appear either 650ms or 1450ms after the cue
        --> finding was if stimulus was presented in a way predicted by the cue (so if cue was like 650ms and then stimulus was displayed actual 650ms later) their reaction time was quicker compared to if the cue did not predict the stimulus (instead of 650 predicted by cue, the stimulus was presented 1450 ms after it)
        ---> this held true for both conditions (whether a long or a short cue was presented),
        ------> if valid following stimulus (so same as predicted) = shorter reaction times ,
        ------> if stimulus following cue was invalid (so not true as predicted) = longer reaction times
        
        ---> reaction time without any cue was 950 ms and acted as baseline / control :3 !!
- - - - Old view: filtering happens as soon as sensory experience received
      - New view: it happens a bit later, as ppl in dichotic listening task first semantically process information before filtering it /thus instead of saying Hello doctor schuman and 973 instead of Hello 7 Schuman (for left ear) and 9 Doctor 3 (for right ear) # #
    - - --> this couldn't explain "lunch line phenomena" where you can always loud and clearly perceive your own name in crowded noisy room even when not paying attention to it
      - ---> lead to change of the "selective filter" into an "attenuation filter" which meant that filtered stimuli not filtered completely, but rather become weakened, so that we dont pay attention to them
  - - - know how of which extracted object features go together spatially (e.g. green color, goes on the square which is actually green) is determined by
        
        ---> “MASTER MAP OF LOCATIONS”
        
        if your attention is focused on this location (e.g. spotlight attention) on the master map (where the object features are combined, it is more likely that this process of combining is correct :3 !! (e.g. that a green square displayed together with read square is actually green and not red :p (which would be illusory conjunction :3!!)
      - combines the extracted object features into actual recognizable objects
- - - - Extinction
        -->they can perceive stimulie on both sides of their visual field, just when more than one stimulus is attenuated too the left or right side affected by neglect will become extinct (as if it wasnt there
      - space based
      - object based
    - - Eye tracking
        --> searching a visual array for a target letter
        --> ppl with neglect might not look at the left or right side as will be obvious in the eye tracker
      - line cancelation test
        --> sheet of paper with lines, they asked to draw a line through each line turning them into a "+" symbol
        --> ppl with neglect will miss lines on either left or right
        
        space based
        
        object based
      - copying objects or scenes
        --> e.g. show picture of a clock they will draw only half of it or really shittily = neglect
      - Two finger test
        --> first finger left side, then finger right side
        ---> patients perceives both !!
        then both at the same time (one righ tside one left side
        --> patient only sees finger on side where there's no neglect !
        ---> called exctinction !!
  - - - Simultanagnosia
        --> is difficulty perceiving the visual field as a whole scene,
        -> comb or spoon highly selective
      - Ocular apraxia
        --> is a deficit in making eye movements (saccades) to scan the visual field, resulting in the inability to guide eye movements voluntarily.
      - Optic ataxia
        ----> a problem in making visually guided hand movements.
        --> deficits in cerebellum, so choppy movements also caused by lack of forward model future calculations of what it will feel like when arm will be in different location in space a few ms from now , which leads to choppy movement cause now has to wait for feedback from arm to adjust movement to be accurate --> produces lag
- - - - priming effect
        --> activity in precuneus and ips in anticipation of cue
        --> these were spatially specific!
      - frontal cortex has mediation effect of attention (see monkey study diagramm page 315)
        --> frontal cortex dmg lead to small ERP responses when focusing attention :3 !!
        --> frontal eyefield stimulation mimicks effect of visual attention
        --> specifically frontal eye fields ( study with monekys :3 !!) performed better if attention was spatially focused on part hat frontal eyyefield would secade over
      - TMS on frontal eyefield
        --> enhaced activity there for both motion task in V5 and gender detection of face
        -
        ---> shows impulses from the FEF actually coded information about the task that is to be performed, indicating that the dorsal system is involved in generating
        --> task-specific, goal-directed attentional control signals #
  - - - If more involuntary attention ventral areas in brain become active
        ---> e.g. Ponser task if cue didnt predict stimulus and stimulus was surprising and thus involuntary grabbed persons attention Temporoparietal junction became active :3 !! #
  - - - supranuclear palsy (PSP)
        dmg to superior colliculie + basal ganglia = trouble shifting their attention + slow to respond to cues
    - - Support:
        --> muscimol / gaba studies in monkeys where deactivated dorsomedial region of pulvinar
        --> dificulties covertly directing attention to contralateral visual field + trouble filtering out distracting info
        --> when gaba antagonist given monkeys suddenly able again to direct attention covertly
        --> pulvinar essentail for cover attention !!
        further support :
        --> ppl with leasion have trouble engaging attention to a cued loation :3 !!
        
        --> contrasts lots with ppl who have dmg in inferior parietal or temperoparietal jungtion ( ventral network)