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									*PROCESS DISSOCIATION TASK*
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 04-14-2015
last updated:  03-10-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-10-2020 Millisecond Software

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BACKGROUND INFO 	
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This script runs the Process Dissociation Procedure by Yonelinas et al (1995).
The Process Dissociation Procedure is a procedure to help separate the contributions of automatic
(here: familiarity) and intentional (here: recollection) processes on cognitive tasks (here: recognition memory).

Reference:
Yonelinas, A.P. & Jacoby, L.L. (1995). The relation between remembering and knowing as bases for recognition:
Effects of size congruency. Journal of Memory and Language, 34, 622-643.

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TASK DESCRIPTION
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Participants study 2 lists of geometrical shapes. The shapes are presented in 2 different sizes. 
The geometrical shapes of both lists as well as an equal number of new shapes are used for a later recognition test 
(Half of the shapes of list 1 and list 2 are presented in their original sizes; half of them change size.
Participants are instructed that the size doesn't matter only the shape itself is of importance).

2 types of instructions are used for the recognition tests:

1) Was presented shape part of list 1? Say 'Yes' if it was or if it looks familiar but you don't recall whether
it's from list 1 or list 2. Say 'No' if you know the item is new or you know it is a shape from list 2.

2) Was presented shape part of list 2? Say 'Yes' if it was or if it looks familiar but you don't recall whether
it's from list 1 or list 2. Say 'No' if you know the item is new or you know it is a shape from list 1.

Participants work through 4 study-test blocks: 2 blocks with instruction 1 ('list1 instructions') 
and 2 blocks with instruction 2 ('list2 instructions').

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DURATION 
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the default set-up of the script takes appr. 25 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: 'processdissociation_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.round:						counts the blocks/rounds

values.instructiontype:				1 = list1 instructions; 
									2 = list2 instructions
																		
values.currentlist:					1 = list1 item; 
									2 = list2 item; 
									3 = list3 (new) item
									
values.size:						1 = small size; 
									2 = big size									
									
values.congruence:					1 = study and test size are the same; 
									2 = study and test size are not the same
									
values.nextitem:					contains the currently selected stimulus itemnumber
stimulusitem:						the presented stimuli in order of trial presentation

response:							the scancode of the response button
										30 - A (left)
										38 - L (right)
										
values.responseCategory:			"Yes" vs. "No"
correct:							correctness of response (1 = correct; 0 = incorrect)
latency: 							the response latency (in ms); measured from onset of stim

congruent items (c):
values.count_11_c:					counts test trials in which a list 1 items is presented under list1 instructions
values.count_12_c:					counts test trials in which a list 1 items is presented under list2 instructions
values.count_21_c:					counts test trials in which a list 2 items is presented under list1 instructions
values.count_22_c:					counts test trials in which a list 2 items is presented under list2 instructions
values.countyes_11_c:				counts how often participant says 'yes' to list1 items under list1 instructions => item1 familiar and recollected
values.countyes_12_c:				counts how often participant says 'yes' to list1 items under list2 instructions => item1 familiar but not recollected
values.countyes_21_c:				counts how often participant says 'yes' to list2 items under list1 instructions => item2 familiar but not recollected
values.countyes_22_c:				counts how often participant says 'yes' to list2 items under list2 instructions => item2 familiar and recollected
values.countno_11_c:				counts how often participant says 'no' to list1 items under list1 instructions => failed recollection; failed familiarity
values.countno_12_c:				counts how often participant says 'no' to list1 items under list2 instructions => correct recollection
values.countno_21_c:				counts how often participant says 'no' to list2 items under list1 instructions => correct recollection
values.countno_22_c:				counts how often participant says 'no' to list2 items under list2 instructions => failed recollection; failed familiarity
(same for incongruent items)

values.values.count_new:			count test trials in which a list 3 item (new) is presented
values.countyes_new:				counts test trials in which a list 3 item (new) is presented and participant replies 'yes' (instead of no) -> False Alarms for new items


(2) Summary data file: 'processdissociation_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)

In this task: p(R ecollection) and p(F amiliarity) are estimated using
Inclusion Measure = p(accepting a target list item = 'yes') = p(Recollection) + p(Familiarity) - p(R&F)
Exclusion Measure= p(accepting a non-target list item = 'yes') = p(Familiarity) - p(R&F)

=> Recollection Estimate = p(R) = Inclusion Measure - Exclusion Measure
=> Familiarity Estimate = Exclusion Measure/p(no recollection) = Exclusion Measure/(1-p(R))

expressions.inclusion: 				probability of saying 'yes' to items from the targetlist 
									('yes' to list1 items under list1 instructions as well as 'yes' to list2 items under list2 instructions)
										(+ separate measures for congruent and incongruent items: expressions.inclusion_c, expressions.inclusion_ic)
										
expressions.exclusion: 				probability of saying 'yes' to items not from the targetlist 
									('yes' to list2 items under list1 instructions as well as 'yes' to list1 items under list2 instructions)									
										(+ separate measures for congruent and incongruent items: expressions.exclusion_c, expressions.exclusion_ic)
										
expressions.recollection: 			probability of recollecting an item: 
									estimated by subtracting the Exclusion measure from the Inclusion measure
										(+ separate measures for congruent and incongruent items: expressions.recollection_c, expressions.recollection_ic)
										
expressions.familiarity:			probability of familiarity of an item: estimated by dividing the Exclusion measure by the probability that item was NOT recollected (= 1-expressions.recollection)
										(+ separate measures for congruent and incongruent items: expressions.familiarity_c, expressions.familiarity_ic)
										
expressions.FA_new:					Commission Errorrate for new items (across instructions)
										(Commission = classifying a new item as an old one)

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EXPERIMENTAL SET-UP 
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2 congruence (congruent, incongruent study-test shape sizes) x 2 types of instructions (list 1 instructions; list 2 instructions)
tested within subjects.

Blocks:
4 Study (list1 -> list2) - Recognition Test Blocks:
-> 2 with instructions 1 (see above)
-> 2 with instructions 2 (see above)
=> order of blocks randomly determined for each participant 

Study Trials:
* 1 between-list trial: 5s (automatically starts list 2)
* 20 trials each: 
-> list shapes are randomly presented for 5s (default; editable parameter) each
-> half the shapes are presented big (by default: image is sized to be 80% of the screen height); 
the other half small (by default: image is sized to be 20% of the screen height)

Test Trials:
* 1 instruction trial: 5s (automatically starts the list)
* 60 trials each: 20 list1 shapes; 20 list2 shapes; 20 new shapes ('list3')
-> half the shapes of each list are presented big (by default: image is sized to be 80% of the screen height); 
the other half small (by default: image is sized to be 20% of the screen height)
-> for list1/list2 shapes: half of the shapes are presented in the same size as during the study phase (congruent); the
other half is presented in the opposite size (incongruent)

NOTE: 
a) before each study-test phase, 20 shapes are randomly assigned to each of the 3 lists.
The shapes are randomly drawn from the pool of 240 shapes (initially) without replacement
=> all 240 shapes will be used over the course of this experiment
=> the assignments will be different for each participant
b) Response key (yes/no) assignment to left and right response keys is counterbalanced by groupnumber

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STIMULI
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provided/generated by Millisecond Software.
240 (20 shapes per list x 3 number of lists/block x 4 blocks) geometric shapes were computer generated by 
randomly selecting 5 points out of 100 possible ones and connecting them.
The size of the 'big' and 'small' shapes can be set under section 'Editable Values'

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INSTRUCTIONS 
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Instructions are not original to the task. They are provided by Millisecond Software
as htm/html pages and can be edited by changing the provided htm/html files.
To edit htm/html-files: open the respective documents in simple Text Editors such as TextEdit (Mac)
or Notepad (Windows).

Note: once the study phase starts, the process (including instructions) are started automatically.
Timing can be controlled via editable parameters (see section "Editable Values")S
	
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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 Assignments: 
/responsekey_left:						the left response key (default: "A")
/responsekey_right:						the right response key (default: "L")

/getReadyDuration:						the duration (in ms) of the get-ready-trial
/liststimduration:							duration in ms of the stim presentation during study (default: 5000ms)
/studybreak:								duration in ms of the break between list1 and list2 (default: 5000ms)				
/testinstructionduration:				duration in ms of the instructions for the recognition test (default: 20s)

/bigstimsize:								size of image size of big stims in % of canvas height (default: 80%)

/smallstimsize:							size of image size of small stims in % of canvas height (default: 20%)
											=> B/S = 4