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									SIMPLE REACTION TIME TASK - visual
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
last updated: 01-26-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

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 runs a simple visual reaction time task. 

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TASK DESCRIPTION	
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The participant gets presented a fixation cross that is followed after variable time intervals 
by a visual target stimulus (here: circle). The participant's task is to press the spacebar as soon as the 
target stimulus appears on the screen. Latency, mean latency, and latency standard deviation 
are recorded in the data file.

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DURATION 
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the default set-up of the script takes appr. 4 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: 'srtvisual_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. 
										
stimulusitem:						the first presented stimulus (=fixation cross)
parameters.focusx:					the x-coordinate of the fixation cross
parameters.focusy:					the y-coordinate of the fixation cross
parameters.focuscolor:				the color of the fixation cross
parameters.focussize:				the size of the fixation cross
stimulusitem:						the second presented stimulus (=target)
parameters.targetcolor:				the current color of the target circle
parameters.targetsize:				the current color of the target circle
parameters.targetx:					the x-coordinate of the target circle
parameters.targety:					the y-coordinate of the target circle
parameters.fixed:					0= fixed position of target; 1 = random position of target
parameters.maxtrialnumber:			the number of trials in a block
trials.SRTT.count	:				counts the SRTT trials run in a given block
values.stiminterval:				the current stimulus interval
latency:							the latency of the response (in ms)
trial.SRTT.meanlatency:				the mean latency in the current block (in ms)
trial.SRTT.medianlatency:			the median latency in the current block (in ms)
trial.SRTT.minlatency:				the fastest response in the current block (in ms)
trial.SRTT.maxlatency:				the slowest response in the current block (in ms)
trial.SRTT.sdlatency:				the standard deviation of the latency responses in the current block
trial.SRTT.varlatency:				the variance of the latency responses in the current block
trial.SRTT.totalmeanlatency:		the mean latency across all trials.SRTT (in ms)
trial.SRTT.totalmedianlatency:		the median latency across all trials.SRTT (in ms)
trial.SRTT.totalminlatency:			the fastest response across all trials SRTT (in ms)
trial.SRTT.totalmaxlatency:			the slowest response across all trials SRTT (in ms)
trial.SRTT.totalsdlatency:			the the standard deviation of the latency responses across all trials SRTT
trial.SRTT.totalvarlatency:			the variance of the latency responses across all trials SRTT


(2) Summary data file: 'srtvisual_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)
									
trial.SRTT.totalmeanlatency:		the mean latency across all trials.SRTT (in ms)
trial.SRTT.totalmedianlatency:		the median latency across all trials.SRTT (in ms)
trial.SRTT.totalminlatency:			the fastest response across all trials SRTT (in ms)
trial.SRTT.totalmaxlatency:			the slowest response across all trials SRTT (in ms)
trial.SRTT.totalsdlatency:			the the standard deviation of the latency responses across all trials SRTT
trial.SRTT.totalvarlatency:			the variance of the latency responses across all trials SRTT


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EXPERIMENTAL SET-UP 
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* By default, the script runs 2 blocks of 20 trials each
* By default, the fixation cross as well as the target stimuli appear in the center of the screen. Changes can be made under 
section Editable Parameter, including changing the script so that the target stimuli appear randomly in one of 9 screen positions.
* By default, the time intervals are randomly chosen  from 2000ms, 3000ms, 4000ms, 5000ms, 6000ms, 7000ms, 8000ms
* By default, the fixation cross is black. 
* By default, the color of the circle is red.
* By default, the color of the screen background is white. 

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INSTRUCTIONS 
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see 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:

targetcolor:							sets the color of the circle; the default is red
targetsize:								sets the size of the circle; the default is 10% of the vertical screen
targetx:								sets the x-coordinate of  the target circle ; the default is the center (50%)
targety:								sets the y-coordinate of the target circle , the default is the center (50%)
focusx:									sets the x-coordinate of the focus stimulus; the default is the center (50%)
focusy:									sets the y-coordinate of the focus stimulus; the default is the center (50%) 
focuscolor:								sets the color of the focus stimulus; the default is black
focussize:								sets the size of the focus stimulus
maxtrialnumber:							sets the number of trials that should be run in a block; the default is 20
screencolor:							sets the background color of the screen
fixed:									determines whether to use the fixed coordinates for the target stimulus (= 0) or to select
										randomly from 9 different screen positions (=1) ;  default is 0