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Measuring reaction time (Studies (Sternberg letter recall / memory search…

- - - - assumptions
        
        there are successive / serial stages but:
        --> not known how many
        --> not known what they do
        
        does not assume pure insertion
        --> doesn't assume that if we omit one stage the processing of the others doesn't change
        
        Rather:
        
        If two different manipulations affect at least one of the same stages (can modify same and a different one), then they interact,
        --> increase in RT = not guaranteed if they only affect same one :3 !!
        --> slopes will not be the same / run parallel but intersect if extended, (starting point = same)
        --> effect on slope angle only :3 !!
        
        if two different manipulation affect two different stages , then they are additive and the reaction time increases :3 !!
        --> slope will be the same / run parallel but starting point(intercept) = will be higher / lower
        --> effect on intercept (beginning) only
        
        increase in reaction time are because
        --> increase in RT = means increase in time spend in one OR MORE STAGES(quality of output of each stage=same)
        --> eg. number 3 and number 3 harder to read, ----> encoding of harder to read might take slightly longer but processing thereafter is the same across the board :3 !! #
        
        --> eg. number 3 and number 3 harder to read, --> encoding of harder to read might take slightly longer but processing thereafter is the same across the board :3 !! (I believe processing happens much much quicker subconscious, there are no stages everything is fluid and parallel and everything can make up for anything else :3 !!
        
        increase in RT = means increase in time spend in one OR MORE STAGES
        ------> BUT!!!! quality produced by each = stays the same :3!!
        
        because quality produced by one stage as output = same it doesn't affect processing time of other stages
        
        other stages can't make up for increased time use by stages before them, hence why reaction time increases :3 !!
      - strength
        --> less assumptions than donders model #
        --> doesn't assume processes in advance :) !!
      - limitations:
        --> only works if serial processing
        --> if the stages are parallel then not possible to disentangle stages so whole modle doesn't work :D!! so basically it doesn't work lol #
        -----> eg. hommel expriment: location (left right) and shape of stimulus interacted cause RT quicker on same side (stimulus present on right side, RT quicker with right hand)
        --> Majority of brain works in parrallel
        --> we need high statistical power to reject H0: there is interaction
      - mechanisms
        
        interaction effects:
        --> if two factors interact they must affect the same stage (slopes interact)
        --> eg. how well visible a stimulus is and the size of the letter string both interact to influence encoding :3 !!
        
        additive effects (favored by science):
        --> effect of one stage, effects another stage (slopes parallel)
        --> eg. bad visibility --> affects encoding --> makes comparing time longer cause harder to process letter string :P
      - additive you start with a 2*2 factorial design
        
        you take reaction time in each of the combinations and see fi they are parallel, if they are parallel, that means that the process actually has two independent stages :) !!
        --> thats how the stages are not assumed but rather disentangled , its like a double disassociation :3 !!
        
        if there is an interaction, that means one of the factors influences one of the stages inside the model, so of the 2 stages its really just 1 stage, cause the one isnt independent but rather just the same stage of processing , thus modulating it :3 !!
    - - pre-processing
      - response selection
      - motor adjustment
    - - reaction time = minimum time required to give correct response in a given task
      - can be mediated by instructng to respond the fastest they can or normal or take time to choose right
        --> basically by adjusting time they have to react :3 !!
      - if using any of the methods above where mean Reaction Time is the outcome:
        
        it also has to be considered how many errors the people made
        ---> because people have individual differences in what they perceive their "fastest or medium" way of answering is, they will take more or less time (deviate from theoretical proposed faster vs more accurate instruction) than other people BUT have higher accuracy
        -----> differences in Reaction time in one condition could thus be, not because of processing but taking more time and making more accurate decisions
        
        to fix that have them run the test at different instruction levels and take the average the (e.g. fastest, equally important, accuracy important :3!!)
        --> however that is unpractical :p !!
        
        Good bridge to second task, where its about ROC curves and criterions, where we want to know how sensitive someone is to a stimulus / that they perceive the stimulus equally well, we adjust how fast they respond / response with hit, false positive etc by adjusting the instructions :3 !!!
    - - assumptions
        
        stages are successive / serial
        
        assuming we actually know what the stages are or happens during the stages / how do they work ..
        
        assumes pure insertion
        --> if we omit / add one stage the processing of the others doesnt change
        
        --> if we change one part of the task (doesnt influence the rest of the task / nothing else changes about the task, eg the effort of the motor response will stay exatly the same if e.g discrimination is added... meh
        
        If this assumption violated (which it is lol) then actual change of omission/add changes time in other processes, but it would be wrongly attributed to the aded / omitted one
        
        Violation shown in ERP studies
        --> A and C = same motor ERP (But doesn't say anything cause ERP not accurate)
        --> B AND C = differences in ERP --> insertion lead to alteration of motor ERP!!
      - How it works
        
        Task A (single RT)
        --> 1 stimulus, 1 possible response
        --> sensory time + motor time
        
        Task B (2 choice RT)
        --> 2 stimulus, each different response
        --> sensory time+ discrimination time+ response selection time + motor time
        
        Task C (disjunctive RT / go/nogo)
        --> 2 stimulus, 1 response (really its 2 responses either pressing the button or no so meh)
        --> sensory time + discrimination time + motor time
        
        Response selection = B - C
        
        stimulus discrimination = C - A
      - limitations
        
        inconsistent results in labs
        --> depends on subjects experience
        
        his substraction lead to negative reaction times..
        --> cause he used the minimum reaction times
        
        nowadays we use mean reaction time
- - - - short wait
      - one letter shown
        
        press button if previously present in letter string
        
        measure reaction time how quickly you pressed
      - some letters shown (letter set)
    - - In this task Serial search and exhaustive
        ---> EXCEPTWHEN the random letter string forms a word :D!! cause then its parallel processing !!!**
    - - exhaustive (favored by science)
        --> search doesnt stop when item found
        --> favoured by science atm :p
        dont believe though #
        
        slope RT of letter there (positive) and letter not there (negative) = parallel
      - self terminating
        --> search stops when letter found :3 !! # #
        --> self terminating doesnt mean sequential :3 ?
        
        slope of RT of letter there (positive) is way smaller < than letter not there (negative)
        --> slope of letter there (positive) = half as big as for negative :3 !!
        
        --> because we only search the letter string until we would find the letter and then stop and react! VS the letter is not there so we search the entire letter string until we react/ not react, so it takes longer :3 !!
  - - - proves parallel processing cause not sequentially searching along the letter string and self terminating each (instead of exhaustive :3 !!)
        
        --> the knowledge of how word is constructed gives hint where the letter is inside the word so its found super quickly
        
        --> sooo its teh same as self terminating because oyu find the letter in teh word way quicker and then stop searchign teh rest of the word if the letter string is an actual word. While you keep on using exhaustive search when the letter is in a random letter string, because no such hint is given :p !!