Holding space bar as key response

Comments

• eduard

  April 2022

  Hi Gio,

  have you seen this (old) discussion? Especially Sebastiaan's code? It might give you a good starting point how to deal with keyrelease responses.

  I would need to register the exact time when the space bar began to be pressed, when it was released, and what was on the screen at the moment

  Perhaps there are other ways, but what comes to my mind is a while loop that has 2 stages. In the first stage it waits for a keydown response, once it registers it, it changes to the second stage and polls for key release responses. All the while, measuring the passing time and adjusting the visual stimulation (independently from the key actions). Something like that:

  key_pressed = False
  start_time = clock.time()
  while True:
      # poll responses
      if not key_pressed: 
             k, t = getDownkey # that isn't a real function, just pseudocode)
             if k is not none:
                  key_pressed = True
       elif key_pressed:
              k, t = getUpkey # also just pseudocode
              break
       # independent of the response, we also measure time and present stimuli
       if clock.time() - start_time > stim_duration: 
             presentNextStimulus() # pseudocode
  
        # if some timeout has been reached, leave the loop
        break
  

  Another thing that might be important is that you seem to use forms. That complicates things, because forms are quite disruptive of the overall experiment. That means, you can't interrupt your form for executing other code (nothing runs in the background of a code, also no releaseKey code). So, there is a fair chance that you need to adapt your code.

  Hope this helps,

  Eduard