ossa1.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Operation Signs Spatial Associations.

Use arrow keys

"""

from expyriment import design, control, stimuli
from expyriment.misc import constants

PLUS = "plus"
MINUS = "minus"

control.set_develop_mode(False)

########### DESIGN ####################
exp = design.Experiment(name="OSSA1",
                        background_colour = constants.C_GREY,
                        foreground_colour = constants.C_BLACK,
                        text_font = "freesans", text_size=28)

# Design: 2 response mappings x 8 stimuli x 10 repetitions
for response_mapping in ["left_plus", "right_plus"]:
    block = design.Block()
    block.set_factor("mapping", response_mapping)
    #add trials to block
    for sign in [PLUS, MINUS]:
        trial = design.Trial()
        trial.set_factor("sign", sign)
        block.add_trial(trial, copies=24)
    block.shuffle_trials()
    exp.add_block(block)

exp.add_bws_factor('mapping_order', ['left_plus_first', 'right_plus_first'])
#prepare data output
exp.data_variable_names = ["block", "mapping", "trial", "sign", "ISI",
                           "btn", "RT", "error"]

#set further variables
t_fixcross = 500
min_max_ISI = [200, 750] # [min, max] inter_stimulus interval
ITI = 1000
t_error_screen = 2000
no_training_trials = 5

######### INITIALIZE ##############
control.initialize(exp)

# Prepare and preload some stimuli
blankscreen = stimuli.BlankScreen()
blankscreen.preload()
fixcross = stimuli.FixCross()
fixcross.preload()
error_beep = stimuli.Tone(duration=700, frequency=2000)
error_beep.preload()

#define a trial
def run_trial(cnt, trial):
    # present Fixation cross and prepare trial in the meantime
    fixcross.present()
    exp.clock.reset_stopwatch()
    ISI = design.randomize.rand_int(min_max_ISI[0], min_max_ISI[1])
    sign = trial.get_factor("sign")
    target = stimuli.TextLine(text=str(sign), text_size=36)
    target.preload()
    exp.clock.wait(t_fixcross - exp.clock.stopwatch_time)
    #present blankscreen for a random interval
    blankscreen.present()
    exp.clock.wait(ISI)
    # Present target & record button response
    target.present()
    btn, rt = exp.keyboard.wait([constants.K_LEFT, constants.K_RIGHT])
    #Error feedback if required
    if block.get_factor("mapping") == "left_plus":
        error = (sign == MINUS and btn == constants.K_LEFT) or \
                (sign == PLUS  and btn == constants.K_RIGHT)
    else:
        error = (sign == PLUS  and btn == constants.K_LEFT) or \
                (sign == MINUS and btn == constants.K_RIGHT)
    #write data and clean up while inter-trial-interval
    blankscreen.present()
    if error:
        error_beep.present()
        exp.clock.wait(t_error_screen)

    exp.data.add([block.id, block.get_factor("mapping"),
                  cnt, sign, ISI, btn, rt, int(error)])
    exp.data.save()
    target.unload()
    exp.clock.wait(ITI)


######### START ##############
control.start(exp)

# permute block order across subjects
if exp.get_permuted_bws_factor_condition('mapping_order') == "right_plus_first":
    exp.swap_blocks(0, 1)

# Run the actual experiment
for block in exp.blocks:
    # Show instruction screen
    if block.get_factor("mapping") == "left_plus":
        instruction = "Press LEFT arrow key for '{0}'\n".format(PLUS) + \
                            "and RIGHT arrow key for '{0}".format(MINUS)
    else:
        instruction = "Press LEFT arrow key for '{0}'\n".format(MINUS) + \
                            "and RIGHT arrow key for '{0}".format(PLUS)
    stimuli.TextScreen("Word Classification Task", instruction +
                       "\n\nPress space bar to start training.").present()
    exp.keyboard.wait(constants.K_SPACE)
    #training trials
    for cnt in range(0, no_training_trials):
        trial = block.get_random_trial()
        run_trial(-1 * (1 + cnt), trial) #training trails has negative trial numbers
    # Show instruction screen
    stimuli.TextScreen("Attention!", instruction +
                       "\n\nThe experimental block starts now.").present()
    exp.keyboard.wait(constants.K_SPACE)
    # experimental trials
    for cnt, trial in enumerate(block.trials):
        run_trial(cnt, trial)

####### END EXPERIMENT ########
control.end(goodbye_text="Thank you very much for participating in our experiment",
             goodbye_delay=5000)