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										Unconscious Reward Task
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 08-13-2018
last updated: 08-21-2018 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Script Copyright © 08-21-2018 Millisecond Software

Millisecond Software thanks Dr. Eric Bijleveld for generously sharing his original script!


BACKGROUND INFO 

											*Purpose*
This script implements the Unconscious Reward Task as described in:

Bijleveld, Custers, E.R. & Aarts, H. (2010). Unconscious reward cues increase invested effort, 
but do not change speed–accuracy tradeoffs,Cognition, 115, 330-335,


											  *Task*
Participants work on simple addition equations (3 + 2 + 6 = 13) and have to decide whether the suggested solution is correct
or incorrect. For correct evaluations, they can earn two types of rewards, either a low reward (max. 1cent) or 
a high reward (max. 50cents) with the caveat that rewards get smaller the longer is takes to respond. 
The take-home reward further depends on the overall accuracy of the participants' responses: the extra money can
only be earned if 90% or more of all responses were correct.
Half the trials present the reward cues subliminally (at 17ms duration); half the trials present the reward cues 
supraliminally (at 300ms).

Task Duration: 15-20 minutes


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

(1) Raw data file: 'unconsciousrewardtask_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 - nevertheless they will be counted in trialnum; 
									by default data is collected unless /recorddata = false is set for a particular trial/block) 

/countTrials:					counts the number of trials run																		
/cueStim:						1 = selects the reward coin with itemnumber 1 (here: 1 cent)
								2 = selects the reward coin with itemnumber 2 (here: 50 cents)
/rewardValue:					stores the value of the reward (here: 1 vs. 50)	
/cueDuration:					stores the duration (in ms) of the reward cue (here: 17ms vs. 300ms)
/mathProblem:					contains the assembled math problem
/corrSolution:					the correct solution to the math problem
/providedSolution:				the computer suggested solution to the math problem
/corrResponse:					1 = the suggested solution is correct; 0 = the suggested solution is incorrect
response:						the participant's response: scancode of response key
									18 = E ('correct')
									23 = I ('incorrect')
/resp:							1 = the suggested solution is accepted as correct; 
								0 = the suggested solution is not accepted as correct									
correct:						accuracy of response: 1 = correct response (participant selected correct response key); 0 = otherwise
latency: 						the response latency (in ms); measured from: onset of math problem until response
/rewardAmount:					the calculated earned reward amount for the current trial
/totalRewardAmount:				the cumulative reward amounts
/takeHomeReward:				the take home reward (depends on performance (90% correct or higher) and totalRewardAmount)

(2) Summary data file: 'unconsciousrewardtask_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 responses across all 56 trials
/totalRewardAmount:					the cumulative reward amounts
/takeHomeReward:					the take home reward (depends on performance (90% correct or higher) and totalRewardAmount)

/propCorrect_reward1duration1:		proportion correct responses for reward 1 (here: 1cent) presented for the short duration (here: 17ms)
/meanRT_reward1duration1:			mean response time (in ms) of correct responses for reward 1 (here: 1cent) presented for the short duration (here: 17ms)
									that were < 7000ms (at 7000ms and above no reward can be earned)
									
/propCorrect_reward1duration2:		proportion correct responses for reward 1 (here: 1cent) presented for the long duration (here: 300ms)
/meanRT_reward1duration2:			mean response time (in ms) of correct responses for reward 1 (here: 1cent) presented for the long duration (here: 300ms)
									that were < 7000ms (at 7000ms and above no reward can be earned)

/propCorrect_reward2duration1:		proportion correct responses for reward 2 (here: 50cents) presented for the short duration (here: 17ms)
/meanRT_reward2duration1:			mean response time (in ms) of correct responses for reward 2 (here: 50cents) presented for the short duration (here: 17ms)
									that were < 7000ms (at 7000ms and above no reward can be earned)
									
/propCorrect_reward2duration2:		proportion correct responses for reward 2 (here: 50cents) presented for the long duration (here: 300ms)
/meanRT_reward2duration2:			mean response time (in ms) of correct responses for reward 2 (here: 50cents) presented for the long duration (here: 300ms)
									that were < 7000ms (at 7000ms and above no reward can be earned)

* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions


EXPERIMENTAL SET-UP

Test: 56 trials
- 28 trials with reward 1 (14 presented at 17ms (7 correct), 14 presented at 300ms (7 correct)); 
28 trials with reward 2 (14 presented at 14 ms (7 correct), 14 presented at 300ms (7 correct))
- trial order is random
- the math problem is randomly (without replacement) selected from the pool of pre-generated 56 problems

Trial Sequence:
-> precue fixation (3000ms)
-> precue mask (400ms)
-> cue (17ms vs. 300ms)
-> postcue mask (583ms vs. 300ms)
-> postcue fixation (1500ms)
-> generic equation cue (1500ms): 'x+x+x=xx'
-> math equation (until response): actual problem presented
-> performance feedback (3000ms): participants learn whether a) they were correct or incorrect and b) how much they earned
-> cumulative earnings feedback (2000ms): participants learn their accumulated earnings
-> iti
(one break after 28 trials)


Reward Calculations: the promised reward decreases by ~14% per s responding
- the rewards per trial (for correct responses) are calculated using the following formula:
actual reward = max. rewardvalue - (max. rewardValue * response time in ms/7000)
=> responses given after 7000ms earn an actual reward value of 0 (same as incorrect responses)


STIMULI
* 56 addition problems generously provided by Dr. Eric Bijleveld (see section Editable Stimuli)
- each problem contains 3 digits (1-9) (repeated digits ok)
- no two of the digits add up to 10

* coins and mask generously provided by Dr. Eric Bijleveld (see section Editable Stimuli)

INSTRUCTIONS
generously provided by Dr. Eric Bijleveld and translated to English by Millisecond Software
(see section Editable Instructions)

DURATION
15-20 minutes

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.

The parameters you can change are:

/pauseTrial:					a rest trial is presented after 28 (default) trials

Duration Parameters:

/readyDuration:					the duration (in ms) of the 'get-ready' trial (default: 3000ms)
/precue_fixationDuration:		the duration (in ms) of the precue fixation cross (default: 3000ms)
/premaskDuration:				the duration (in ms) of the precue mask (default: 400ms)
/shortcueDuration:				the duration (in ms) of the short reward cue  (default: 17ms)
/longcueDuration:				the duration (in ms) of the long reward cue  (default: 300ms)
/combinedCueMaskDuration:		the duration (in ms) of the combined cue and postcue mask (default: 600ms)
									Note: the post-cue mask will be longer for the short cue duration
/postcue_fixationDuration:		the duration (in ms) of the postcue fixation cross (default: 1500ms)
/genericEquationCueDuration:	the duration (in ms) of the (X+X+X=XX) stimulus before actual math problem is presented (default: 1500ms)
/performanceFeedbackDuration:	the duration (in ms) of the performance feedback (default: 3000ms)
/earningFeedbackDuration:		the duration (in ms) of the total earnings feedback (default: 2000ms)
/iti:							the duration (in ms) of the intertrial interval (default: 3000ms)
/pauseDuration:					the duration (in ms) of the rest/pause trial (default: 10000ms)

Stimulus Sizing Parameters:

/cueSize:						the proportional (to canvas) size of the reward cue (default: 30%)
/fixationSize:					the proportional (to canvas) size of the fixation cross (default: 8%)
/problemSize:					the proportional (to canvas) size of the math problem (default: 5%)


Response Key Assignment:

/correctResponseKey:			the scancode of the 'correct' response key (here: 18)
									see Tools-> Keyboard Scancodes for potential scancodes
/correctResponseKeyLabel:		the label attached to the correct response key label (here: E)
/incorrectResponseKey:			the scancode of the 'incorrect' response key (here: 23)
/incorrectResponseKeyLabel:		the label attached to the correct response key label (here: I)


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