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							Food Stroop Task -- Blocked Version
							(with keyboard input)
SCRIPT INFO

last updated: 02-04-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC
Copyright © 02-04-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements a blocked Food Stroop created by Millisecond Software.
It is based on the FoodStroop.iqx that uses voice recording instead of keyboard input.


											  *Task*
Participants get words of 6 different conditions (e.g. unhealthy and healthy foods, animal names, and color words)
in 4 different colors and are asked to press one of 4 keyboard keys as fast as possible.
											  
DATA FILE INFORMATION: 
The default data stored in the data files are:

(1) Raw data file: 'FoodStroop_keyboardinput_raw*.iqdat' (a separate file for each participant)

build:							Inquisit build
computer.platform:				the platform the script was run on
date, time, subject, group:		date and time script was run with the current subject/groupnumber 
blockcode, blocknum:			the name and number of the current block
trialcode, trialnum: 			the name and number of the currently recorded trial
									(Note: not all trials that are run might record data; by default data is collected unless /recorddata = false is set for a particular trial/block) 
response:						the participant's response (scancode of response button)
correct:						the correctness of the response (1 = correct; 0 = incorrect)
latency: 						the response latency (in ms)
'values.stimword':				contains the current stim word
values.stimworditemnumber: 		stores the itemnumber of the current stimword
'values.stimcolor':				contains a numeric representation of the current word's display color: 1=black, 2=blue, 3=green, 4=red, 5=yellow
'values.condition': 			contains a numeric representation of the current condition: 1=congruent, 2=incongruent, 3=HPF, 4=NTF, 5=HPFA, 6=NTFA

(2) Summary data file: 'FoodStroop_keyboardinput_summary*.iqdat' (a separate file for each participant)

script.startdate:				date script was run
script.starttime:				time script was started
script.subjectid:				subject id number
script.groupid:					group id number
script.elapsedtime:				time it took to run script (in ms)
computer.platform:				the platform the script was run on
/completed:						0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run)
/propcorrect:					overall proportion correct of test trials
/meanRT:						overall mean correct latencies of test trials (in ms)
+ separate measures for each of the 6 experimental conditions


EXPERIMENTAL SET-UP

1 Practice Block: 4 trials with "GREEN", "RED", "CAT", "BANANA"

6 Test Blocks: 6 x 12 trials tested in blocked* design by default
1) Congruent Color Words: presents 12 color words (red, blue, green, yellow) in the congruent color (3 repetitions of each color word with constraint that the same color cannot presented consecutively)
2) Incongruent Color Words: presents 12 color words (red, blue, green, yellow) in incongruent colors (3 repetitions of each color word; each time it is presented in a different incongruent color with constraint that the same color cannot presented consecutively)
3) unhealthy food choices: presents 12 unhealthy food choices in 4 colors (colors randomly selected with constraint that the same color cannot presented consecutively )
4) healthy food choices: presents 12 healthy food choices in 4 colors (colors randomly selected with constraint that the same color cannot presented consecutively )
5) animals (control for unhealthy food choices): presents 12 animals in 4 colors (colors randomly selected with constraint that the same color cannot presented consecutively)
6) animals (control for healthy food choices): presents 12 animals in 4 colors (colors randomly selected with constraint that the same color cannot presented consecutively)
- order of blocks is randomly selected

*blocked: the set-up of this script also allows to run the condition in a mixed design (without the constraint of repeated color selections)

Trial Sequence:
Fixation Cross for 200ms -> Stim word until verbal response (recorded but not evaluated)

STIMULI
see section Editable Stimuli

INSTRUCTIONS
see section Editable Instructions

EDITABLE CODE:
check below for (relatively) easily editable parameters, stimuli, instructions etc. 
Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment.

Responsekeys/Labels:
/keyred/redlabel:							scancode/label for the red response button (default: 32 -> d)
/keygreen/greenlabel:						scancode/label for the green response button (default: 33 -> f)
/keyblue/bluelabel:							scancode/label for the blue response button (default: 36 -> j)
/keyyellow/yellowlabel:						scancode/label for the yellow response button (default: 37 -> k)

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