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									   VISUAL STATISTICAL LEARNING I
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
last updated:  03-12-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-12-2020 Millisecond Software

Millisecond Software LLC thanks Turk-Browne et al (2005) for providing the 12 original shapes used in this study!

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BACKGROUND INFO 	
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The script "Visual Statistical Learning I"  adapts the procedure used by Fiser & Aslin (2002) to study 
the unprompted statistical learning of temporal relationships inherent in a visual presentation of moving shapes:

Reference:

Fiser, J. & Aslin, R.N. (2002). Statistical Learning of Higher-Order Temporal Structure from Visual Shape Sequences. 
Journal of  Experimental Psychology: Learning, Memory, and Cognition, 28, 458-467.

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TASK DESCRIPTION	
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Participants are presented with a 5-6min "movie", in which 12 basic shapes moved one after the other 
across the monitor from, seemingly "changing" from one shape into another when they cross a black bar 
in the center of the screen.  The "change", however, is not random as the 12 shapes were grouped into 4 triplets 
with strict rules regarding to which shape can follow another, e.g. triplets have to stay together and have to be 
presented always in the same order (A->B->C). To test whether participants have learned the inherent temporal shape 
relationships, the movie-triplets (=familiar) are pinned against "novel" triplets in a balanced  forced-choice task, 
in which participants are asked to decide which of the two triplet pairs are more familiar to them.									  

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DURATION 
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the default set-up of the script takes appr. 10 minutes to complete
(if no task duration is provided, please contact Millisecond Software
(katjab@millisecond.com)

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

(1) Raw data file: 'vsl_fiser_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. 
																				
list.tripletsequence.currentindex:			the index of the selected tripletsequence (e.g. the third sequence in the list)
values.selectedletter:						the letter presented in the shape presentation sequence
values.inde:								the letter position in the shape presentation sequence										
values.A-values.L:							the indices of the shapes (from the item list shapes) that are assigned to shapes A-L
values.novel11-values.novel43:				the indices of the shapes (from the item list shapes) that are assigned to novel triplets
values.pairing:								determines which familiar and which novel triplets were compared and in which order
											(e.g. 15 -> triplet pair ABC against novel triplet 1, familiar first)
											15 = old ABC triplet, novel1 triplet
											51 = novel1 triplet, old ABC triplet
											...
											48 = old JKL triplet, novel4 triplet
											84 = novel4 triplet, old JKL triplet									
									
values.shape1-values.shape6:			the shapes presented during the forced-choice trials with shape 1 being the first

response:								the SCANCODE of the key-response of the participant
										2 (scancode) => number '1' (first sequence more familiar)
										3 (scancode) => number '2' (second sequence more familiar)
										
responsetext:							the character code of the key pressed										

correct:								whether this is a correct response (1= correct; 0 = error)
latency:								how long the participant took to make response (in ms); measured from onset of task question


(2) Summary data file: 'vsl_fiser_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)

expressions.prop_correct:			proportion correct familiar triplet identifications
expressions.meanRT_correct:			mean latency (in ms) of correct familiar triplet identifications
expressions.SD_correct:				standard deviation (in ms) of correct familiar triplet identification latencies

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EXPERIMENTAL SET-UP 
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PART I: Shape Sequence "Movie":
This script implements a simple imitation of the original movie used by Fiser & Aslin (2002). 
In Fiser and Aslin's study, participants watched a shape appear from under a black bar that was positioned 
in the middle of the screen. The shape then moved to the left  of the screen,  changed direction and  moved back 
towards the bar, behind which it disappeared once more. When it "reappeared", the shape had "morphed" 
into the next shape, which stayed on the same trajectory and moved to the right side of the screen, 
changed direction and  moved back towards and behind the bar again (and so on). Each shape was presented for 1s.

The underlying shape sequence in this script meets the same criteria used by Fiser & Aslin (2002):
 	(1) 12 shapes divided into 4 triplets
	(2) Triplets stay together
	(3) Each triplet is presented 24 times (=288 shape presentations)
	(4) No immediate repeats of triplets (e.g. ABCABC)
	(5) No repeat of triplet pairs (e.g. ABCDEFABCDEF)
	(6) Each triplet appears the same number of times in each third of the sequence (8times)

In addition, this script offers the opportunity to randomly
	(1) select from a pool of 10 possible sequences that all meet these criteria. (=> vary sequence across participants)
	(2) assign the 12 shapes to the 4 triplet pairs (=> triplet pairs are not constant across participants)

PART II: Forced-Choice
In the Forced-Choice part of the experiment, the script pins the 4 familiar triplet pairs 
(ABC, DEF, GHI, JKL - from the sequence) against  4  novel triplets (AEI, DHL, GKC, JBF)*. 
These novel triplets are made up of shapes that had never directly followed each other during the 
sequence presentation - changes to these triplets can be made under trial.assignments (e.g. change triplets to 
partial triplets as used in Fiser & Aslin (2002), Experiment2).

Participants get to view 2 sequences of 3 shapes. Each shape is presented for default=500ms** 
with a break of 1s (s. Fiser & Aslin).
Shapes appear in a left- right-left sequence (s. Fiser & Aslin). Participants are asked to decide 
which one is more familiar.
(default TASK: press "1" for first, press "2" for second -> change keys to press under values).
Each of the 16 triplet-pairings is presented twice, once with the familiar sequence being presented 
first and once with the familiar sequence being presented second. The resulting 32 possible 
forced-choice tasks are selected at random.

*Fiser & Aslin (2002) do not specify the novel triplet combinations used. 
The triplet combinations used in this script are taked from  Turk-Browne et al (2005). 
The automaticity of visual statistical learning. Journal of Experimental Psychology: General, 134, 552-564.

**Fiser & Aslin (2002) do not specify the screen duration of the individual shapes in the forced-choice task.

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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 simple page elements and can be edited either by changing
the provided htm/html files or directly under Editable Instructions.
To edit htm/html-files: open the respective documents in simple Text Editors such as TextEdit (Mac)
or Notepad (Windows).

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STIMULI
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Millisecond Software LLC thanks Turk-Browne et al (2005) for providing the 12 original shapes used in this study!
See section Editable Stimuli

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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:

waitforcedchoice:		determines the pretrialpause before the first shape triplets are shown in the forced-
						choice task (default is 1s)
						
leftkey:				the left key used to respond if the first sequence is more familiar
						(default = "1")
						
rightkey:				the right key used to respond if the second sequence is more familiar
						(default = "2")