[open] Inhibition Experiment with Variable Stimuli Presentations

Comments

• eduard

  April 2016 edited 7:39AM

  Hi,

  The easiest implementation that comes to my mind is based on inline_scripts. In those, you can define the list that you want to present in each round in the beginning of a block, so that in the actual loop you only have to access the right index. The structure of your experiment could then look like this:
  First, you use add a loop-sequence structure to your experiment. In this one, you define an inline_script, in which you set all the lists you need, and another loop-sequence structure (the loop for the trials), in which you put a sketchpad (stimulus presentation), a keyboard_response (response collection) and a logger (write everything to file). How to use the last three items, you probably learned from the tutorials. What to put in the inline_script follows here:

  import random
  
  # put all the image filenames in a list and make sure the files are in the 
  # file pool
  all_pictures = ['pic1.JPG','pic2.JPG',...]
  #set parameters
  no_images = 48
  no_1repeat = 22
  no_2repeat = 15
  
  # a list with 22 repeated images selected for the list created above
  one_rep = random.sample(all_pictures,no_1repeat)
  
  # a list with 15 repeated images selected for the first repetition list
  two_rep = random.sample(one_rep,no_2repeat)
  
  var.all_stim = all_pictures + one_rep + two_rep
  random.shuffle(var.all_stim)
  

  The variable var.all_stim is now a list with 85 randomized images names. In your trial_sequence you can access one image by one image from this list.

  I hope this helps.

  Good luck,

  Eduard

  
• caamitchell11

  April 2016 edited 7:39AM

  Thanks Eduard!

  Your response was incredibly helpful. I will try this approach :-)

  Thanks again.

  Claire