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									SIMPLE REACTION TIME TASK - visual
SCRIPT INFO

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

Copyright © 01-26-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script runs a simple visual reaction time task. 

											  *Task*
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.

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

(1) Raw data file: 'SRTVisual_raw*.iqdat' (a separate file for each participant)

build:								Inquisit build
computer.platform:					the platform the script was run on
date, time, subject, group:			date and time script was run with the current subject/groupnumber 
blockcode, blocknum:				the name and number of the current block
trialcode, trialnum: 				the name and number of the currently recorded trial
										(Note: not all trials that are run might record data; by default data is collected unless /recorddata = false is set for a particular trial/block) 
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)

script.startdate:					date script was run
script.starttime:					time script was started
script.subjectid:					subject id number
script.groupid:						group id number
script.elapsedtime:					time it took to run script (in ms)
computer.platform:					the platform the script was run on
/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


EXPERIMENTAL SET-UP
* 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. 

INSTRUCTIONS
see section Editable Instructions

EDITABLE CODE:
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

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