Return to the Symbol Counter Task page
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										*SYMBOL COUNTER TASK*
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-04-2013
last updated:  11-05-2019 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 11-05-2019 Millisecond Software
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BACKGROUND INFO 	
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This script implements the Symbol Counter Task to study allocation of attentional resources 
within working memory.

The implemented procedure is based on:

Garavan, H., Ross, T.J., Li, S.J., & Stein, E.A. (2000). A parametric manipulation of central executive 
functioning. Cereb Cortex, 10, 585-92.

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TASK DESCRIPTION	
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Participants are presented 18 sequences of small and big squares and have to keep a separate count for each
of the two squaretypes. Afterwards, participants are asked to select the count for each squaretype out of 
20 possible options and receive feedback.

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DURATION 
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the default set-up of the script takes appr. 18 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: 'symbolcountertask_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.squarenumber:						the current length (number of squares presented)
values.switchintensity:						the currently selected switchintensity (1 = low; 2 = medium; 3 = high)
values.switchfrequency:					the calculated switch frequency (based on squarenumber and switchintensity)
values.switchpositions:					a string variable that stores all switchpositions in order from lowest to highest
values.symbolorder:						string variable that stores the order of the presented symbols (1 = small; 2 = big )
values.countsymbol1:						counts the number of symbol1 (small squares) cards that have been presented
values.countsymbol2,:						counts the number of symbol2 (big squares) cards that have been presented

dropdown.countsymbol1.response:			the participant's count of symbol 1 (small squares) cards
dropdown.countsymbol2.response: 			the participant's count of symbol 2 (big squares) cards

values.correctcount1:					1 = participant counted symbol1 cards correctly; 
									0 = participant did not count symbol1 cards correctly
									
values.correctcount2:					1 = participant counted symbol2 cards correctly; 
									0 = participant did not count symbol2 cards correctly
									
correct:								1 = both of participant's count are correct; 
									0 = otherwise
									
values.rt:							latency of response (selecting the two counts)



(2) Summary data file: 'symbolcountertask_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)

values.totalcorrect:					number of times participants was correct on both counts
expressions.perc_totalcorrect:			percentage of times participant was correct on both counts

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EXPERIMENTAL SET-UP 
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6 number of sequential squares x 3 types of switchfrequencies (high, medium, low) = 18 trial sequences

* Number of Squares: 	11, 12, 13, 14, 15, 16
* Switch Frequencies: 	number of times the sequence switches from one symbol to the other

						high -> floor(number of squares /2); e.g. floor(15/2) = 7
						medium -> floor (number of squares/4); e.g. e.g. floor(15/4) = 3
						low -> 1

TRIAL SEQUENCE:

trial.start  -> 
 -> 
trial.presentSquares (loops until all squares are presented) 
-> surveypage.symbolcount 
-> trial.feedback 
-> trial.rest

*observed trial sequence (default):
	repeat for as many squares as need to be shown (trial.presentSquares)
	* fixation cross for 100ms
	* square for 1500ms

	Then:
	* select correct counts out of 20 possible options (0-20); maximum time to accomplish this is 
	12s (surveypage.symbolcount)
	* receive feedback in the form of correct counts for 1000ms (trial.feedback)
	* rest for a predetermined amount of time before next trial starts (a clock presents number of seconds) 
	(trial.rest)
		=> 18 trials divided into 2 parts by a longer rest

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STIMULI
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2 types of black squares: small vs big
presented in form of pictures that can be easily substituted by others

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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.

The parameters you can change are:

/symbol1_label:					the label of symbol1 (here: SMALL Square)
/symbol2_label:					the label of symbol2 (here: BIG Square)
								Note: if you use different symbols, change the labels below

/pictureheight:					the height of the symbol picture (default: 50%)

Duration Parameters:			
/fixationcrosspresentation:			fixation cross duration (default: 100ms)
/cardpresentationduration:			duration of card presentation (default: 1500ms)
/responseduration:				time participants have to select countnumbers (default: 12000ms)
/feedbackduration:				time feedback (here: correct counts) is presented  (default: 1000ms)
/restduration_regular:				time of the resting trial (default: 15000ms) between trial sequence
/restduration_long:				time of rest in between the first 9 trials and the second 9 trials (default: 120000ms)
/showcorrectcounts:				debug element: 
								if set to true: correctcounts are presented in red during the count selection trial
								false = counts are not presented (default).
/skippractice:						false = a practice sequence is run (default); true = no practice is given