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									  TRANSITIVE INFERENCE TASK
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 04-18-2014
last updated:  03-12-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-12-2020 Millisecond Software

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BACKGROUND INFO 	
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This script implements a nonverbal Transitive Inference Task similarly to the one described in:

Frank, M.J., Seeberger, L.C. & O’Reilly. R.C. (2004). By Carrot or by Stick: Cognitive
Reinforcement Learning in Parkinsonism. Science, 306, 1940-1943

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TASK DESCRIPTION	
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Participants work through a learning and a test phase. 
During the learning phase participants get presented 4 overlapping pairs of symbols (AB, BC, CD, DE)
and have to learn to pick the winning symbol of each pair (A > B > C > D > E).
Throughout the learning phase participant are given positive and negative feedback.
During the test phase, two novel pairs (AE and BD) are presented amongst the training pairs.
No feedback is given during the testing phase.

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DURATION 
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the default set-up of the script takes appr. 8 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: 'transitiveinterferencetask_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 such as feedback trials. Thus, trialnum 
										may not reflect the number of main trials run per block. 
										
values.phase:						1 = learning; 2 = test									
values.pair:						current pair of symbols (e.g. "AB")
stimulusitem.1-stimulusitem.2:		the presented stimuli in order of trial presentation
									Note: does not need to correspond to spatial presentation of stimuli

response:							the participant's response (scancode of response button)
										30 = A
										38 = L
										
values.selectedletter:				the selected letter
values.winletter:					contains the winning letter during learning
correct:							the correctness of the response (1 = correct; 0 = error)
latency: 							the response latency in ms; measured from onset of stims


(2) Summary data file: 'transitiveinterferencetask_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)
									
block.learningphase.totalcount:	how many learning phases participants went through

values.percA_AB_training -
values.percD_DE_training:			percent correct for the different pairings during the last training session

values.percA_AB_test-
values.percD_DE_test:				percent correct for the known pairings during test

expressions.percA_AE -
expressions.percB_BD:				percent correct for the novel pairings during test

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EXPERIMENTAL SET-UP 
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Letter-Symbol-Assignment: each of the provided 5 symbols gets randomly assigned to 'play the role' of letters A, B, C, D, E

Learning Phase: 
* each learning block runs for 80 trials (20 per symbol pair -> can be edited via parameters.trialnumber_learning)
* it can be controlled via editable parameters whether certain learning criteria have to be met before
moving on to the test phase.
=> if learning criteria are set in place, the learning block will be repeated if not all criteria are met
within the current learning block and the learning cycle starts afresh.

Test Phase:
* the test block runs for 120 trials (20 per symbol pair -> can be edited via parameters.trialnumber_test)

Trial Set-up:
The left-right position of the symbol pairs is counterbalanced across each block
-> symbol A appears on the left side in 50% of the trials 

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STIMULI
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The stimuli are 5 Hiragana characters presented in Frank et al (2004).
Their size and location can be easily controlled via section Editable Parameters.

To use a different set of images, simply replace the stimuli under
section Editable Stimuli -> item.symbols

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INSTRUCTIONS 
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The instructions are not the originals. They can easily 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:

/responsekey_left:						the response key for symbol on the left (default: "A")
/responsekey_right:						the response key for symbol on the right (default: "L")

/x_right:								horizontal coordinate of the right symbol in screen percentages (default: 65%)
/x_left:								horizontal coordinate of the left symbol in screen percentages (default: 35%)
/symbolheight:							the height of the symbol image in screen height percentages (default: 40%)

/trialnumber_learning:					the number of trials in a learning session (default: 80 -> 20 per symbol pair)
/minA_AB-
/minD_DE:								minimum proportion of winning symbol-selections in all 4 learning pairs that have to be met in the current learning block (default: 0.6 for all)
											Note: to remove a criterion, set the corresponding value to 0. In that case, any selection or none
											of the corresponding letter (A, B, C, D) fulfills the criterion. If all values are set to 0, the learning phase
											will be as long as specified under parameters.trialnumber_learning.
																
/trialnumber_test:						the number of trials in the test session (default: 120 -> 60 per symbol pair)

/feedbackduration:						the duration of the feedback stimuli in ms (default: 1000ms)