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									DIGIT SYMBOL SUBSTITUTION TASK - mouse input
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
(reusing some matrix code from the Inquisit Information Sampling Script by David Nitz)
Date: 09-27-2012
last updated: 01-08-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 01-08-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script is based on the computerized Inquisit version of the WISC Coding Task (DigitSymbolSubstitutionTask.iqx) developed by
Amy Finn (Ph.D), John Gabrieli (Ph.D.) and Julia Leonard.
Symbols provided by Millisecond Software.

This script version uses mouse (touch) input instead of keyboard input.

											  *Task*
Participant are presented with a 18 (columns) x 16 (rows) matrix. Odd rows contain symols,
even rows contain empty answer boxes (18x8 = 144).
The task is to translate the symbols into digits with the help of a provided key within a 2 min time frame. 
Participants are asked to select the correct digit from digit buttons placed below the matrix.


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

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

build:							Inquisit build
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) 
expressions.box					ordinal number of the box within the grid for the current symbol
trialcode:						type of current response trial
response:						scan code of key pressed for current symbol (distinguishes responses with number pad vs standard numeric keys)
values.response:				digit value of key pressed for current symbol
correct:						1 if response is correct, 0 if response is incorrect
expressions.correctanswer:		the correct digit for the current symbol
latency:						time in milliseconds for the current response
values.correctcount:			total count of correct responses
values.errorcount: 				total count of erroroneous responses
expressions.totalseconds:		maximum time in seconds allowed for the task
expressions.secondspercorrect:	average number of seconds required for each correct response

(2) Summary data file: 'DigitSymbolSubstitutionTaskMI_summary.iqdat' (Inquisit Lab: a separate file per 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)
/completed:						0 = script was not completed; 1 = script was completed (all conditions run)

expressions.totalseconds:		maximum time in seconds allowed for the task
values.correctcount:			total count of correct responses
values.errorcount: 				total count of erroroneous responses
expressions.secondspercorrect:	average number of seconds required for each correct response


EXPERIMENTAL SET-UP:

(A) PRACTICE:
* 9 practice boxes that appear in gray (practice grid boxes are presented separately from the complete grid)
* 3 of these are already filled in with digits 1-9
* 6 need to be filled in by participant
* the box that needs to be filled in next is highlighted in a different color
* if the answer is correct, the answer is filled in the box and the next practice box is highlighted
* if the answer is incorrect, a text stimulus (in red) appears that reminds participant to correct
the answer. In addition, the box (with the incorrect answer choice) turns red.
* once all practice boxes are filled in correctly, participants press the space bar to continue
* after a final instruction screen comes up, participants press the space bar to start the test
* the complete grid appears and the timed portion of the test starts

(B) TIMED TEST:
* the first presented coding matrix/grid contains 135 test boxes (135 = 144 - 9 practice boxes)
(if another coding matrix is necessary, it will contain 144 test boxes)
* there is no feedback
* the next box that needs to be filled in is highlighted in a different color
(highlighted boxes move from row to row, left to right)
* participant cannot correct their answers nor jump ahead.
* after two minutes the test ends.

(C) ORDER OF SYMBOLS:
the order of the symbols can be edited under section EDITABLE LISTS
Follow instructions.

(D) CANVASSIZE:
In order to provide roughly the same size set-up on different monitors, a specific pixel resolution can be
set under DEFAULTS (for example: 1024px,768px). To change the pixelsize, go to DEFAULTS and change /canvassize.

!!!However, there is no absolute relationship between a pixel and any "real", 
physical measurement unit (mm, cm, inches, etc.). It's different on each monitor.
If the same size is REQUIRED, you can use script MonitorCalibration.iqx to calibrate your monitor.
Transfer the data stored for values.canvassize (in MonitorCalibration.iqx) into
/canvassize = under the DEFAULTS section in this script.


INSTRUCTIONS:
All instruction stimuli are presented under INSTRUCTIONS. Instructions are either 
pages, text stimuli, or instruction images. If instructions need to be changed on images,
new images need to be created (e.g. in PowerPoint) and saved under the current file names.

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:

/timelimit:							default duration (120000ms =>2min) for the timed portion of the test in ms

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