[open] Running timers for two stimuli concurrently with inline script

tombrophy

Hello all, I'm quite new to programming and to Open Sesame (thanks for the software and all the feedback you give on here!) so my apologies if this question seems very basic.

I'm currently designing an experiment where I will have two forms of sound stimuli being played to the participants. One form is a metronome that will repeat every 500ms. The second form is a randomly chosen sound that will play back at a randomly chosen time interval. At the moment I have both of these as if statements embedded in a while loop. Each of the pieces of code will work individually but when executed together the metronome plays every 500ms until the randomly chosen sound plays, at which time the metronome completely stops.

Here is the code as it currently is:

time_range = range(3000, 6000)
play_time = random.choice(time_range)   # Choose a time value between 3-6s
print play_time
start_time = self.time()    # Initialise a starting clock value 
deviants = [deviant1, deviant2, deviant3, deviant4, deviant5]
reaction_keys = keyboard(exp, keylist = ['space'], timeout = 2000)
iteration = 0
metronome_timer = self.time()
while iteration < 5:
    deviant_time = self.time() - start_time
    reaction_timer = self.time()
    metro_range = self.time() - metronome_timer
    if metronome_timer + 500 == self.time():
        metronome_timer = self.time()
        print metronome_timer
        metronome.play()
        outlet.push_sample([2]) # LSL Marker
    if deviant_time == play_time:
        deviant_chosen = random.choice(deviants) # Choose sound
        deviant_chosen.play() # Play sound
        outlet.push_sample([1]) # LSL Marker
        if deviant_chosen == deviant1:
            print 'Deviant 1 played'
        if deviant_chosen == deviant2:
            print 'Deviant 2 played'
        if deviant_chosen == deviant3:
            print 'Deviant 3 played'
        if deviant_chosen == deviant4:
            print 'Deviant 4 played'
        if deviant_chosen == deviant5:
            print 'Deviant 5 played'
        response, timestamp = reaction_keys.get_key()
        response_time = self.time() - reaction_timer
        #while response_time < 2000: # This while loop is used for gathering reaction times still doesn't work without it
        #   if response != None:
        #       response_time = self.time() - reaction_timer
        #       print 'Response time is %d' %response_time
        #       break
        #   else:
        #       print 'User did not respond'
        #   response_time = self.time() - reaction_timer
        if deviant_chosen in deviants: 
            deviants.remove(deviant_chosen) # Remove used items from list
        play_time = random.choice(time_range)
        start_time = self.time()
        iteration = iteration + 1
        if iteration == 5:
            standard.stop()




exp.set('response', response)
exp.set('response_time', response_time)

From the reading I've done it seems as though threading may be necessary to execute this but as a novice coder I would appreciate any help pointing me towards the simplest solution.

Thanks!

eduard

Hi Tom,

I don't think threading will be necessary. Probably this can all be fixed by using conditions in a smart way.

One thing that isn't clear to me is how often/how long is this loop supposed to last? Until participants responded, or is there some timeout?

Here a bit of code, that might simplify a few things.

import random

play_time = random.randrange(3000,6000)   # Choose a time value between 3-6s
print play_time

orig_deviants =  [deviant1, deviant2, deviant3, deviant4, deviant5]
deviants = [deviant1, deviant2, deviant3, deviant4, deviant5]
random.shuffle(deviants)

# A timeout of 2000 ms is pretty long. Opensesame can't do anything
# else during a timeout. So, it is better to have a brief timeout, 
# but loop over it
reaction_keys = keyboard(exp, keylist = ['space'], timeout = 20)

deviant = True
iteration = 0
# Initialise a starting clock value. One is enough 
start_time = self.time()    
while iteration < 5:
    if deviant and self.time()-start_time()>play_time:
        deviant_chosen = deviants.pop() # Choose sound
        deviant_chosen.play() # Play sound
        outlet.push_sample([1]) # LSL Marker 
        deviant = False # used to make this if statement to be entered only once
        print 'deviant %s played'%(orig_deviants.index(deviant_chosen)+1)
    # plays every 490-510 ms (use the modulo for that)
    met_time = (self.time-start_time)%500
    if  met_time<10 or met_time > 490:
        print metronome_timer
        metronome.play()
        outlet.push_sample([2]) # LSL Marker

        response, timestamp = reaction_keys.get_key()
        if response != None:
            response_time = self.time() - timestamp
        #else:
        #    print 'User did not respond'
        if deviant_chosen in deviants: 
            iteration = iteration + 1
        play_time = random.choice(time_range)
        start_time = self.time()


# What is this "standard?"
standard.stop()
# note your response will now only be set one to the values of the last response
# if you want to log each response you have to do it in the while loop
exp.set('response', response)
exp.set('response_time', response_time)

I haven't tested the code. It's probably not entirely correct, but I still hope it is useful for you. Let me know, if you need more advice, or if I misunderstood your intentions.

Good luck.

Eduard

tombrophy

Hi Eduard,

Thank you very much! This has been very helpful. I've had to alter your code slightly to get it closer to what I want it to do, and remove a few parts that were giving error messages. The length of the loop is dictated by the deviants; i.e. when all five deviants have been played the loop should finish. To this end I have moved some of the code around. I have also specified that the metronome should play at exactly 500ms. The audio playback now seems to be working well so thank you very much.

I do have a follow up question that I hope you can help me with regarding collecting keyboard responses. What I want is to have two separate keyboard responses with the space bar recording the response time after the deviant stimulus and the shift key recording how early or late the participant's estimation of the metronome time is. You mentioned above that these should be within the while loop but I am unsure of how to code them. Any advice you could offer would be much appreciated. Here's my code as it is currently:

time_range = random.randrange(3000,6000)   # Choose a time value between 3-6s
print time_range


deviants = [deviant1, deviant2, deviant3, deviant4, deviant5]
random.shuffle(deviants)

# A timeout of 2000 ms is pretty long. Opensesame can't do anything
# else during a timeout. So, it is better to have a brief timeout, 
# but loop over it
reaction_keys = keyboard(exp, keylist = ['space'], timeout = 20)


standard.play()


deviant = True
iteration = 0
# Initialise a starting clock value.
start_time_1 = self.time() 
start_time_2 = self.time()
while iteration < 5:
    if deviant and self.time()-start_time_1>time_range:
        deviant_chosen = random.choice(deviants) # Choose sound
        deviant_chosen.play() # Play sound
        outlet.push_sample([1]) # LSL Marker 
        if deviant_chosen in deviants:
            iteration = iteration + 1
            deviants.remove(deviant_chosen)
        #print 'deviant %s played'%(orig_deviants.index(deviant_chosen)+1)
        time_range = random.randrange(3000,6000)
        start_time_1 = self.time()
    # plays every 490-510 ms (use the modulo for that)
    met_time = self.time()-start_time_2
    if  met_time == 500:
        print met_time
        metronome.play()
        outlet.push_sample([2]) # LSL Marker

        response, timestamp = reaction_keys.get_key()
        if response != None:
            response_time = self.time() - timestamp

        #else:
        #    print 'User did not respond'
        start_time_2 = self.time()


standard.stop()

By the way the "standard" within the code is a longer piece of audio that is playing constantly in the background.

Cheers,

Tom

eduard

Hi Tom,

You can have to separate keyboard items that allow either for a shift or a space response. Inside the while loop you would then do keyboard.get_key() twice and save each result in a separate variable.

Does this make sense?

Eduard