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								*EVENT-BASED PROSPECTIVE MEMORY TASK*
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 09-06-2016
last updated:  03-11-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-11-2020 Millisecond Software

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BACKGROUND INFO 	
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This script implements a computerized Event-based Prospective Memory (PM) Task based on
Smith & Bayen (2006).
Prospective Memory (event based) = Remembering to do something in the case a certain event happens.

Reference:

Smith, R.E, & Ute J. Bayen, U.J. (2006). The Source of Adult Age Differences in Event-Based Prospective Memory: 
A Multinomial Modeling Approach. Journal of Experimental Psychology: Learning, Memory, and Cognition , 32, 623–635.

for stimuli selection:
Smith, R. E., & Bayen, U. J. (2004). A multinomial model of event-based prospective memory. 
Journal of Experimental Psychology: Learning, Memory, and Cognition, 30, 756–777.

Battig, W. F., & Montague, W. E. (1969). Category norms of verbal items in 56 categories: 
A replication and extension of the Connecticut category norms. 
Journal of Experimental Psychology, 80, 1–46.

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TASK DESCRIPTION
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Participants run a color-matching task. During a baseline phase they see a sequence of 4 colored squares followed by
a word probe that either repeats one of the square colors (then press 'y') or doesn't (then press 'n'). 
During the prospective memory task phase, the basic task stays the same but every 10th word is a target
word (previously introduced and studied) that requires a different (or additional) response: press key
'z'.

!Note: due to the nature of the task, the task is not supported on touchscreen devices
(the touchscreen devices would present a z-responsekey throughout the baseline/PM task, thus potentially 
serving as an additional PM reminder)

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DURATION 
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the default set-up of the script takes appr. 25 minutes to complete.
Test Duration: ~15 min
Break: 10min
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DATA FILE INFORMATION 
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The default data stored in the data files are:

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

PM = Prospective Memory

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.order:						order of stim lists used for baseline-PM (Prospective Memory) task: "AB" vs. "BA"
values.phase:						"task practice", "PM training", "baseline", "PM task"
values.trialcount_Phase:			counts the number of trials run in each phase 
values.list:						stim list currently used: "A" vs. "B"
values.trialtype:					"target-match", "target-nomatch", "filler-match", "filler-nomatch"
values.targettype:					"target" vs. "filler"
values.matchtype:					"match" vs. "nomatch"
values.stim:						stores the currently presented probe stimulus
response:							the participant's response for the currently recorded trial

values.response_task:				stores the scancode of the response button hit after stim was presented: 
											21 = yes; 
											49 = no
											
values.correct_task:				accuracy of color-matching task response: 1 = task response was correct; 0 = otherwise
		
values.rt_task:						lateny (in ms) of color-matching task response
									- it's either measured from onset of stim or
									- from positive PM response	(during PM phase only)
										
values.PMresponse:					1 = PM (prospective memory) response was made; 
									0 = no PM response was made (if applicable during PM phase)
									
values.rt_PM:						latency (in ms) of PM response (if applicable during PM phase)
									- it's either measured from onset of stim or
									- from task response
										
values.responseSequence:			"task only", "PM only", "task-PM", "PM-task"
values.color:						stores the color of the probe
values.color1:						stores the color of the first square
values.color2:						stores the color of the second square
values.color3:						stores the color of the third square
values.color4:						stores the color of the fourth square

values.targetRecall:				stores all recalled targets during the recall training

values.recall:						1 = all targets correctly recalled
									0 = otherwise
										
						
(2) Summary data file: 'prospectivememorytask_colormatchingmask_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)
									
/propCorrect_filler1:				proportion correct filler trials during baseline
/meanRT_filler1:					mean latency (in ms) of correct filler trials during baseline
/propCorrect_filler2:				proportion correct filler trials during PM-task phase (based only on trials when task response precedes PM response or task response is only response)
/meanRT_filler2:					mean latency (in ms) of correct filler trials during PM-task phase (based only on trials when task response precedes PM response or task response is only response)

/propCorrect_PMresponses:			proportion correct target trials (=hits) during phase 'PM task'
/propFalseAlarms:					proportion of False Alarms (=positive PM response) during filler trials during phase 'PM task'
/nr_hits:							number of correct PM responses during PM task phase
/nr_FA:								number of False Alarms during PM task phase


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EXPERIMENTAL SET-UP 
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Phase 'Task Practice':
- 6 trials running filler match and filler nomatch trials in random order
(if block A is run first, the stimuli are selected randomly from list A, otherwise from list B)
- errorfeedback is presented for 500ms

Phase 'Baseline':
- samples stimuli from list A (targetsA, fillerA) or list B (targetsB, fillerB) => order of A/B is counterbalanced by groupnumber 
(odd groupnumbers run:AB; even groupnumbers run:BA)
- 62 test trials (6 target trials: 3 match/3 nomatch; 56 filler trials: 28 match/28 nomatch)
- target trials: 10th, 20th, 30th, 40th, 50th, 60th trial 
(!!!BUT: targets are indistinguishable from fillers and don't require any specific response)
	- it is randomly determined which of the 6 targets to present
	- it is randomly determined whether the trial is a match or a nomatch trial
- the order of the remaining 56 filler trials (match vs. nomatch) is randomly determined as are the presented stimuli

Trial Sequence:
square1(500ms)->blank(250ms)->square2(500ms)->blank(250ms)->square3(500ms)->blank(250ms)->square5(500ms)->blank(250ms)
->Probe until response -> ITI: 1000ms (Note; during phase 'PM task' filler and target trials collect possible additional responses
during the intertrial interval also)


Phase 'PM training': 
- all 6 targets presented on screen for study (self-paced)
- recall test: 6 textboxes (targets need to be entered in any order - will get converted to lowercase letters automatically)
- recall is repeated as long as it takes for all 6 targets to be recalled correctly
- a break follows the 'PM training' phase

Phase 'PM task':
- samples stimuli from the list not run during baseline
- 62 test trials (6 target trials: 3 match/3 nomatch; 56 filler trials: 28 match/28 nomatch)
- target trials: 10th, 20th, 30th, 40th, 50th, 60th trial (!target trials require a PM response)
	- it is randomly determined which of the 6 targets to present
	- it is randomly determined whether the trial is a match or a nomatch trial
- the order of the remaining 56 filler trials (match vs. nomatch) is randomly determined as are the presented stimuli

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STIMULI
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2 lists: A vs. B with 62 stimuli each (6 targets and 56 fillers)
- Each target comes from from a different category (= 6 target categories per list)
- Filler items come from the same target categories as the targets from their respective lists.

Millisecond Software attempted to recreate the original lists using the procedure outlined in Smith & Bayen (2006), p. 626.
More info under section Editable Stimuli. The selected words can easily be exchanged for others. 

colors: 
- blue, green, red, yellow, white
- probe color is selected randomly without replacement for each trial with the constraint that:
	- each of the 5 colors is used equally often in match trials (65 = 62 test trials + 3 task practice trials)
	and nomatch trials (65 = 62 test trials + 3 task practice trials)
- color of squares is randomly determined with the constraint that no color is repeated within the same trial
(=> in match trials: one color has to be the probe color but its position is randomly determined)
- all stimuli are presented on a black background

size:
- size can be edited under section "Editable Parameters"

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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).
	
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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.

/ squareDuration:				duration (in ms) of square presentation (default: 500ms)
/ ISI:							duration (in ms) of black interstimulus interval following each square (default: 250ms)
/ ITI:							intertrial interval (in ms) after each response (default: 1000ms)
/ breakDuration:				duration of the break (in ms) before the Prospective Memory task phase (default: 600000ms = 10min)

/ probeSize:					the size of the probes in % of canvas height (default: 3%)
/ squareSize:					the size of the squares in % of canvas height (default: 30%)

/ yesResponsekey:				the yes responsekey (default: "Y")
/ noResponsekey:				the no responsekey (default: "N")
/ PM_Responsekey:				the prospective memory (PM) task key (default: "Z")