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							PROCESS DISSOCIATION TASK
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 04-14-2015
last updated: 01-21-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 01-21-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script runs the Process Dissociation Procedured published in:

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.

			
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).

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))


											  *Task*
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').


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

(1) Raw data file: 'ProcessDissociation_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) 
/round:							counts the blocks/rounds
/instructiontype:				1 = list1 instructions; 2 = list2 instructions
/size:							1 = small size; 2 = big size
/currentlist:					1 = list1 item; 2 = list2 item; 3 = list3 (new) item
/congruence:					1 = study and test size are the same; 2 = study and test size are not the same
/nextitem:						contains the currently selected stimulus itemnumber
stimulusitem:					the presented stimuli in order of trial presentation
response:						the participant's response
/response:						"Yes" vs. "No"
correct:						correctness of response (1 = correct; 0 = incorrect)
latency: 						the response latency (in ms)

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

/count_new:						count test trials in which a list 3 item (new) is presented
/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)

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)
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)
									(and separate measures for congruent and incongruent items)
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)									
									(and separate measures for congruent and incongruent items)
Recollection: 					probability of recollecting an item: estimated by subtracting the Exclusion measure from the Inclusion measure
									(and separate measures for congruent and incongruent items)
Familiarity:					probability of familiarity of an item: estimated by dividing the Exclusion measure by the probability that item was NOT recollected (= 1-expressions.recollection)
									(and separate measures for congruent and incongruent items)
/FA_new:						False Alarm rate for new items (across instructions)


EXPERIMENTAL SET-UP
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

STIMULI
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'

INSTRUCTIONS
are not original; they are provided by Millisecond Software and can be edited under
section "Editable Instructions"
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

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:

/responsekey_left:						scancode of the left response key
											Note: scancodes under Tools -> Keyboard Scancodes (default: 30)
/responsekey_left_label:				label of the left response key (default: 'A')
/responsekey_right:						scancode of the right response key
											Note: scancodes under Tools -> Keyboard Scancodes (default: 38)
/responsekey_right_label:				label of the right response key (default: 'L')

/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

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