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									   ANTI-SACCADE TASK
										(keyboard version)
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-25-2016
last updated:  03-24-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-24-2020 Millisecond Software

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BACKGROUND INFO 	
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This script runs the AntiSaccade Task, a test of inhibitory control, with keyboard input as described in:

Friedman, N. P., Miyake, A., Young, S. E., DeFries, J. C., Corley, R.
P., & Hewitt, J. K. (2008). Individual differences in executive
functions are almost entirely genetic in origin. Journal of Experimental
Psychology: General, 137, 201–225.

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TASK DESCRIPTION	
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Participants are asked to focus on a fixation cross in the center of the screen.
A brief flash is presented on either to the right or the left side of the fixation cross.
The brief flash is followed by the target stimulus on the opposite side of the flash.
The target is either a left-pointing, a right-pointing, or an up-pointing arrow and 
it disappears quickly.
Participants are asked to press the  '←' key on the keyboard if it's a left-pointing arrow, 
to press the  '→' key on the keyboard if it's a right-pointing arrow, 
and to press the  '↑' key on the keyboard if it's an up-pointing arrow.

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DURATION 
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the default set-up of the script takes appr. 10 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: 'antisaccadetask_keyboard_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.phase:						"practice" vs. "test"
values.fixationDuration:			duration (in ms) of fixationcross
values.targetLocation:				target is located: 'left' vs. 'right' to the fixation cross
values.targetDirection:				target arrow points to: 'left' vs. 'right' vs. 'up'
values.stim:						contains the currently presented arrow image
response:							the participant's response (scancode of response button)
correct:							the correctness of the response (1 = correct; 0 = incorrect)
latency: 							the response latency (in ms); measured from onset of target stim


(2) Summary data file: 'antisaccadetask_keyboard_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.properrors_AS:			error rate for AntiSaccade task
expressions.meanRT_AS:				mean latency (in ms) of correct AntiSaccade responses
expressions.SD_AS: 					standard deviation of latencies (in ms) of correct AntiSaccade responses

* 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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2 (targetLocations: right vs. left) x 3 (targetDirections: right vs. left vs. up) tested within participants (=> 6 different trial types)

- 1 Practice Block: 18* practice trials (change number of trials under section BLOCKS), order of trials randomly determined
Errorfeedback is provided during Practice only

- 1 Test Block: 90 trials, 15 trials per each trial type (change number of trials under section BLOCKS), order of trials randomly determined
Note*: number of trials different from Friedman et al (2008)

	Trial-Sequence:
	(1) Fixation cross: variable duration, randomly sampled (with replacement) btw. 1,500 and 3,500 ms (in 250ms intervals)
	(2) Flash (150ms): a yellow square appears either on the opposite side the target appears on (AntiSaccade)
	(3) Target (175ms): target appears
	(4) Mask (until response): gray mask covers target
	(5) ITI: blank screen for 0ms (editable) before fixation cross returns

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STIMULI
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- stimulus sizes can be edited under section Editable Parameters
- stimulus left/right positions can be edited under section Editable Parameters

target stimuli are left, right and up pointing arrows

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INSTRUCTIONS 
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are provided by Millisecond Software 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:
check under EDITABLE CODE 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:

User Interface (UI) parameters:
/fontsize_fixation:					sets the height of the fixation cross in canvas % (default: 15%)
/ targetsize:						sets the height of the target images in canvas % (default: 5%)
/ flashSize:						sets the height of the flash stimulus in canvas % (default: 15%)
/ maskSize:							sets the height of the mask stimulus in canvas % (default: 15%)

/stimduration:						sets the max. duration of the target presentation in ms (default: 2500ms)
/iti:								intertrial interval in ms (default: 500ms)

/leftPos:							coordinate of the left stimulus location in canvas width percentages (default: 25% -> center is 50%)
/rightPos:							coordinate of the right stimulus location in canvas width percentages (default: 75% -> center is 50%)

/leftKey:							the scancode of the left responsekey (default: 203)
/rightKey:							the scancode of the right responsekey (default: 205)
/upKey:								the scancode of the right responsekey (default: 200)