[solved] collecting free responses and response time

Dorgar

Hi!

First of all I'm completely new to OpenSesame so my question may be a noob question. I'm trying to create a simple procedure - show stimuli for period of time (say 60s) and collect every keypress (to be exact 4 keys) that subject makes, along with time interval between each keypress (to know for how long thet percive some givan state) Is it possible to do so?

Thanks in advance!

sebastiaan

Hi Dorgar,

That's possible, but you'll need to use some inline code to do so. The script below shows how to loop through a number of responses, reducing the timeout with each response so that the total timeout is 60s. This should hopefully get you started.

For more info, see:

• http://osdoc.cogsci.nl/python-inline-code/keyboard-functions

from openexp.keyboard import keyboard

# Uncomment for 0.25 and before
# exp = self.experiment

# Nr of responses
n_resp = 4

 # 60s total timeout
total_timeout = 60000

# Get the onset of the sketchpad change 'my_sketchpad'
# to the name of the preceding sketchpad.
start_time = self.get('time_my_sketchpad')

# Create a keyboard object
my_keyboard = keyboard(exp)

# Initially set all responses to some default value, so
# they aren't empty if a timeout occurs
for i in range(n_resp):
    exp.set('response_%d' % i, 'timeout')
    exp.set('response_time_%d' % i, 'timeout')

# Collect multiple responses using a loop
for i in range(n_resp):

    # The timeout for this response
    timeout = total_timeout - self.time() + start_time
    resp, resp_time = my_keyboard.get_key(timeout=timeout)

    # Timeout occurred!
    if resp == None:
        break

    # Log the response and response time
    exp.set('response_%d' % i, my_keyboard.to_chr(resp))
    exp.set('response_time_%d' % i, resp_time - start_time)

Cheers!
Sebastiaan