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									Evaluative Conditioning Task
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Script Author: Sean Draine, Ph.D. (seandr@millisecond.com) for Millisecond Software, LLC
last updated:  12-13-2019 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 12-13-2019 Millisecond Software

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BACKGROUND INFO 	
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This script implements the Evaluative Conditioning Task to facilitate implicit attitude formation using
classical conditioning. The implemented procedure is based on:

Olson, M.A. & Fazio, R.H. (2001). Implicit Attitude Formation through Classical Conditioning.
Psychological Science, 12, pp. 413-417.

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TASK DESCRIPTION	
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Participants view a slideshow of randomly presented words and pictures (or pairs thereof). They are instructed
to press the Spacebar whenever a target is presented (e.g. 'Sprite').
Amongst the presented items are pairings of positive unconditioned stimuli (e.g. positive words)
with a (to be) conditioned stimulus CS+ (e.g. 'coke') as well as pairings of negative unconditioned stimuli
with a (to be) conditioned stimulus CS- (e.g. 'pepsi').

The pairings of UCSs and CSs (here: Coke vs. Pepsi) are counterbalanced by groupnumber.

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DURATION 
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the default set-up of the script takes appr. 12 minutes to complete

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DATA FILE INFORMATION 
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The default data stored in the data files are:

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

build:								The specific Inquisit version used (the 'build') that was run
computer.platform:				the platform the script was run on (win/mac/ios/android)
date, time, 						date and time script was run 
subject, group, 					with the current subject/groupnumber
script.sessionid:					with the current session id

blockcode, blocknum:			the name and number of the current block (built-in Inquisit variable)
trialcode, trialnum: 				the name and number of the currently recorded trial (built-in Inquisit variable)
										Note: trialnum is a built-in Inquisit variable; it counts all trials run; even those
										that do not store data to the data file.
										
currentblock:					the number of the current block
stimulusitem.1:					will be empty (first stim presented as clearscreen)
stimulusitem.2:					second presented stim
stimulusitem.3:					if the second presented stim was paired, this column stores the third presented stim

response:							the participant's response; scancode of keyboard response
										0 = no response, 
										57 = spacebar
										
latency: 							the response latency (in ms); measured from onset of second stim

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

computer.platform:				the platform the script was run on (win/mac/ios/android)
script.startdate:					date script was run
script.starttime:					time script was started
script.subjectid:					assigned subject id number
script.groupid:					assigned group id number
script.sessionid:					assigned session id number
script.elapsedtime:				time it took to run script (in ms); measured from onset to offset of script
script.completed:				0 = script was not completed (prematurely aborted); 
									1 = script was completed (all conditions run)
									
meanRT_targets:					the overall mean latency of correct responses to all targets
percentcorrect_targets:		the overall percent correct rate of target identifications

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EXPERIMENTAL SET-UP 
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* 2 CS-UCS pairings (positive-Coke/negative-Pepsi vs. negative-Coke/positive-Pepsi) are tested between participants.
Assignment is done by groupnumer

odd groupnumbers run block.AABB = pairings of US-A (positive) with CS-A (coke), US-B (negative) with CS-B (pepsi)
even groupnumbers run block.ABBA = pairings of US-A (positive) with CS-B (pepsi), US-B (negative) with CS-A (coke)

* script runs 5 blocks - each block runs a different target (predetermined order)
* each block runs 86 trials: 60 distractors, 18 targets, 4 pairings of positive UCS and CS+, 4 pairings of negative UCS and CS-
order of the trials is randomly determined
* default stimulus/exposure duration: 1500ms 
* optional Intertrial Interval that shows a blank page for 17ms

Note:
	The script uses the following category assignments:
	cs A: Coke
	cs B: Pepsi
	us A: Positive
	us B: negative 
	
	
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STIMULI
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all stimuli can be edited under section Editable Stimuli

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INSTRUCTIONS 
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can be edited under section Editable Instructions

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EDITABLE CODE 
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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.

The parameters you can change are:

	exposureDuration:
		Controls trial duration, i.e., how many ms each stimulus remains on the screen. 
	csPicSize:
		Controls size of conditioned stimulus pictures (coke or pepsi).
	ucPicSize:
		Controls size of unconditioned stimulus pictures (negative or positive).
	ucFontHeight:
		Controls size of unconditioned text (negative or positive).
	defaultFontHeight:
		Specifies the height of distractor words.
	defaultPicSize :
		Controls the size of distractor, target, and blank stimuli. 
	ITI:
		optional Intertrial Interval in ms (default: 17ms)