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											*Dots Task*
										(keyboard version)
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 04-02-2018
last updated:  09-28-2021 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 09-28-2021 Millisecond Software
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BACKGROUND INFO 	
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This script implements the Dots Task. The Dots Task is a spatial incompability task with 
arbitrary shape stimuli similar to the Simon Task. The Dots Task was designed to 
target working memory and inhibition.

Dots Task Reference:

M.C. Davidson, D. Amso, L.C. Anderson, A. Diamond (2006). Development of cognitive control and 
executive functions from 4 to 13 years: Evidence from manipulations of memory, inhibition, 
and task switching. Neuropsychologia 44, 2037–2078

Simon Task Reference:

Simon, J.R. and Wolf, J.D. (1963). Choice reaction times as a function of angular stimulus-response 
correspondence and age. Ergonomics, 6, 99-105.

Bialystok, E., Craik, F. I. M., Klein, R., & Viswanathan, M. (2004). Bilingualism, Aging, 
and Cognitive Control: Evidence From the Simon Task. Psychology and Aging, 19(2), 290-303.

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TASK DESCRIPTION
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Participants are presented trials with either a red circle or a blue circle that appear to the 
left or right of a fixation cross.
If participants see a red circle, they are asked to press the corresponding left or right 
response key (=congruent trials). For example, if the red circle is left to the fixation cross, 
participants are asked to press the left 'A' response key.
If participants see a blue circle, they are asked to press the opposite response key (=incongruent trials).
For example, if the blue circle is left to the fixation cross, participants are asked to 
press the right 'L' response key.

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DURATION 
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the default set-up of the script takes appr. 2 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: 'dotstask_mi_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.practice:					1 = practice block; 
									0 = test
									
values.position:					1 = stimulus is positioned on the left; 
									2 = stimulus is positioned on the right
									
values.congruence:					1 = congruent trial; 
									2 = incongruent trial
									
values.prevCongruence:				the congruence of the previous trial (important for mixed condition only)

values.switch:						1 = switch trial (trial type changed from congruent to incongruent or vice versa);
									2 = nonswitch trial (trial type stayed the same)
									
values.countSwitch:					counts the number of switch trials per block									
									
stimulusitem:						the presented stimuli in order of trial presentation

response:							scancode of the the participant's response key
										30 = A = left
										38 = L = right
										
correct:							accuracy of response: 
										1 = correct response; 
										0 = otherwise
										
Latency: 							the response latency (in ms); measured from: onset of stim

list.ACC_practice.mean:				the proportion correct during the current practice block
values.countPractice:				counts the number of practice blocks run


(2) Summary data file: 'dotstask_mi_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)

Practice Performance:									
									
values.countPractice:				counts the number of practice blocks run
values.practiceACC:					the highest proportion correct in one of the practice blocks (if not run, propCorrect = 0)

values.practicePass:				1 = participant successfully passed the practice session; 
									0 = otherwise
									
Test Performance:									

expressions.propCorrect:			proportion correct across all test trials
expressions.meanRT:					mean latency of correct responses across all test trials
									
expressions.propCorrect_switch:		proportion correct across switch trials
expressions.meanRT_switch:			mean latency of correct responses across switch test trials
									switch trial: switch from congruent to incongruent trial and vice versa

expressions.propCorrect_nonswitch:	proportion correct across nonswitch trials
expressions.meanRT_nonswitch:		mean latency of correct responses across nonswitch test trials									
									
expressions.propCorrect_congruent:	proportion correct across congruent test trials
expressions.meanRT_congruent:		mean latency of correct responses across congruent test trials

expressions.propCorrect_incongruent:proportion correct across incongruent test trials
expressions.meanRT_incongruent:		mean latency of correct responses across incongruent test trials

expressions.SimonEffect	:			ms difference in "[mean corrRT Incongruent] - [mean corrRT Congruent]"
									positive value: participants responded faster when 
									stimulus location and response button location were congruent 
									("stimulus-response compatibility") => Simon Effect
									[negative value: participants responded faster when 
									stimulus location and response button location 
									were incongruent]
									
									

* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions

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EXPERIMENTAL SET-UP 
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1. Practice Block(s): a maximum of 3 (default, can be set under section Editable Parameters) practice blocks of 
8 trials. If participants reach a performance of 75% correct (default, can be set under section Editable Parameters) 
during any of the blocks, the test block is started - otherwise the script is aborted after 3 unsuccessful 
practice blocks. During practice, participants receive positive feedback for 500ms  if they
press the correct response button. For incorrect responses as well as noresponses, participants will get a 
reminder of the rules and have to retry the trial (at this point, only correct responses are accepted to 
move to the next trial).

2. Test: 10 'red circle' trials (5 red circles left, 5 red circles right), 10 'blue circle' trials 
(5 blue circle left, 5 blue circle right)
	=> random order with constraint that max. 3 of the same trials can be run consecutively
	=> number of switch trials will vary (minimum number of switch trials = 6 for 20 trials)
		switch trial: switch from congruent to incongruent trial and vice versa	
	
Note: number of trials per block can be set under section Editable Parameters

Trial Sequence:
stimulus (circle)-> max. 1750ms (editable) -> iti: 1000ms (editable)
(timings can easily be changed under section Editable Parameters)
	
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STIMULI
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provided by Millisecond Software - can be edited under section Editable Stimuli

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INSTRUCTIONS 
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provided by Millisecond Software - can be edited under section Editable Instructions

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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:

/congruentStim:						stores the label used for the congruent stim (default: "RED circle")
/incongruentStim:					stores the label used for the incongruent stim (default: "BLUE circle")
									Note: if the stimuli are changed, picture.congruentStim and picture.incongruentStim need
									to be updated accordingly

/minPracticeACC:					the minimum practice performance (proportion correct) to let participants move from a 
									practice block to a test block (default: 0.75)
								
/maxPracticeRepeats:				number of times a practice blocks can be repeated before the script is aborted (default: 3)
/numberPracticeTrials:				the number of practice trials per practice block (default: 8)

/numberTestTrials:					the number of test trials per test block (default: 20)
									Note: the number of trials should be divisible by 4
									
/readyDuration:						the duration (in ms) of the get-ready-trial
/stimDuration:						the duration (in ms) of the stimulus presentation (= response timeout) (default: 1750)
/iti:								the intertrial interval (in ms) (default: 1000)

/picSize:							the proportional sizing (proportional to canvas height) of the pictures (default: 10%)
/fixationSize:						the proportional sizing (proportional to canvas height) of the fixation cross (default: 15%)
/left_x:							the left x-coordinate in canvas percentage (default: 30%)
/right_x:							the right x-coordinate in canvas percentage (default: 70%)
									Note: left edge of canvas = 0%, right edge of canvas = 100%
									(canvas = portion of the screen dedicated for the script)

Key Assignment: 
/leftKey:							the left response button (default: "A")
/rightKey:							the the right response button (default: "L")