How to change the stimuli list presented in a task depending on participant's response

Comments

• eduard

  April 2023 edited April 2023

  Hi Stone,

  when things seem very complicated to implement it is often a good indication that the approach is not ideal. In your specific case, you shouldn't try to dynamically generate a loop table (I don't even think this is possible). Instead you can use Python (inside inline_scripts) to generate lists of task parameters that more or less correspond to the columns in the loop table. For example, your participant chose 20 in the form. Then you can do in an inline_script (run phase) following that form:

  # assume var.n_congruent_trials exists and is set to 20
  # assume var.n_total_trials exists and is set to 24
  var.congruency = var.n_congruent_trials * ['congruent'] + var.n_total_trials * ['incongruent']
  
  

  That you can then also shuffle to make it random

  import random
  random.shuffle(var.congruency)
  

  and finally match it with the other parameters

  avail_words = ['red', 'green', 'blue', 'black']
  avail_colors = ['red':'#00FFFF', 'green':'#FF00FF', 'blue':'#FFFF00', 'black':'#FFFFFF']
  cr_map = ['red':'r', 'green':'g', 'blue':'b', 'black':'f']
  var.words = 6 * avail_words
  random.shuffle(var.words)
  var.colors = []
  var.correct_responses = []
  for trial_idx, word in enumerate(var.words):
      if var.congruency[trial_idx] == 'congruent':
            var.colors.append(avail_colors[word])
            var.correct_responses = cr_map[word]
      else:
           temp_colors = avail_colors.remove(word)
           chosen_word = random.choice(temp_colors)
           var.colors.append(avail_colors[chosen_word])
           var.correct_responses = cr_map[chosen_word]
  

  Now you have four lists that have 24 items. So you can put a loop/sequence after that inline_script, put another inline_script as first item in that sequence, and add there (in the prep phase):

  var.colour = var.colors.pop(0)
  var.word = var.words.pop(0)
  var.incongruency = var.congruency.pop(0)
  var.correct_response = var.correct_responses.pop(0)
  

  And now you're set.

  Does that make sense?

  Eduard

  ps. I have not tested the code, so there might be some errors. But I hope you get the general point.