4 4AFC interleaved staircases
Posted: Mon Oct 12, 2015 12:55 pm
Hi all, I am looking into buying Psykinematix Sharp (the edition for use with the Bits# card by CRS). I downloaded the trial version so far and I am impressed by the structure of the software. Not that it's easy, but it's well thought. I want to buy this software for a very specific experiment and want to make sure that I can do it before investing on the Sharp edition. I was unable so far to figure out how to program this experiment.
Long story short, I want to measure sensitivity in 4 different eccentricities (i.e. Top, Bottom, Left and Right). This means that I need 4 different stimuli each one presented on a different location (i.e. T, B, L, R). I want to use a staircase for each stimulus (therefore 4 different staircases) and these to be interleaved. The task for the observer will be to identify the location of the stimulus and therefore the task will be a 4AFC (T, B, L and R), however, each stimulus will only be presented in one location and the staircase should only accept this location as a correct response and all the others as wrong.
For example, the Top stimulus is presented, the subject has four alternatives (T, B, L, R) responds T (correct response) then randomly the Left stimulus is presented, the subject has 4 alternatives, responds R (wrong response), then randomly the Bottom stimulus is presented, the subject responds B (correct response) etc etc.
Any ideas whether this is doable?
Best
Thanasis
Long story short, I want to measure sensitivity in 4 different eccentricities (i.e. Top, Bottom, Left and Right). This means that I need 4 different stimuli each one presented on a different location (i.e. T, B, L, R). I want to use a staircase for each stimulus (therefore 4 different staircases) and these to be interleaved. The task for the observer will be to identify the location of the stimulus and therefore the task will be a 4AFC (T, B, L and R), however, each stimulus will only be presented in one location and the staircase should only accept this location as a correct response and all the others as wrong.
For example, the Top stimulus is presented, the subject has four alternatives (T, B, L, R) responds T (correct response) then randomly the Left stimulus is presented, the subject has 4 alternatives, responds R (wrong response), then randomly the Bottom stimulus is presented, the subject responds B (correct response) etc etc.
Any ideas whether this is doable?
Best
Thanasis