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							MISMATCHED NEGATIVITY ODDBALL PARADIGM
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 02-25-2015
last updated:  03-10-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-10-2020 Millisecond Software

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BACKGROUND INFO 	
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This script implements the Mismatched Negativity Oddball Paradigm as published in

Bramon,E., Croft, R.J, McDonald, C., Virdi, G.K., Gruzelier, J.G., Torsten Baldeweg, T., Sham, P.C.,
Frangou, S. & Murray, R.M. (2004). Mismatch negativity in schizophrenia: a family study. 
Schizophrenia Research, 67, 1– 10.

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TASK DESCRIPTION	
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Participants sit in comfortable chairs while the script plays a series of tones (mix of Standard and Oddballs) 
to them over headphones. Participants are instructed to keep their eyes open and to disregard the sounds.
Different portsignals are sent for Standard and Oddball sounds.

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DURATION 
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the default set-up of the script takes appr. 7 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: 'mismatchednegativityoddball_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.stimtype: 					1 = standard; 2 = oddball
stimulusitem1/stimulusitem.2:		the presented stimuli in order of trial presentation
script.elapsedtime:					time it took to run script (in ms); measured from onset to offset of script


(2) Summary data file: 'mismatchednegativityoddball_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)

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EXPERIMENTAL SET-UP 
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- script runs 3 blocks block.MNO of 400 trials each
- each block.MN0 randomly selects the order of 340 standard (85%) and 60 oddball sounds (15%)
- standard sounds play for 25ms and oddball sounds play for 50ms
- an interstimulus interval (isi) of 300ms (editable parameter) is added to each sound
- port signals that coincide with the onset of stimuli are sent along with type of tone

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STIMULI
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Tones created in Audacity by Millisecond Software LLC

standard: 1000hz, 25ms duration, 5-ms rise/fall time
oddball: 1000hz, 50ms duration, 5-ms rise/fall time
(both should be played at 80db)

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INSTRUCTIONS 
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can changed under section Editable Code -> 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:

/isi:					interstimulus interval (isi) in ms (default: 300ms)
						(isi: time between offset of one stimulus and onset of another)

/standardduration:		duration of the standard tone in ms (default: 25)

/oddballduration:		duration of the oddball tone in ms (default: 50)
						Note: if these durations are changed, the corresponding soundfiles also need to change