___________________________________________________________________________________________________________________ MISMATCHED NEGATIVITY ODDBALL PARADIGM ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 02-25-2015 last updated: 02-25-2022 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 02-25-2022 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ 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. ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ 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. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 7 minutes to complete ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ 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 session: 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. stimtype: 1 = standard; 2 = oddball stimulusitem1/stimulusitem.2: the presented stimuli in order of trial presentation 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) inquisit.version: Inquisit version run computer.platform: the platform the script was run on (win/mac/ios/android) startdate: date script was run starttime: time script was started subjectid: assigned subject id number groupid: assigned group id number sessionid: assigned session id number elapsedtime: time it took to run script (in ms); measured from onset to offset of script completed: 0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run) ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ - 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 ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ 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) ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ can changed under section Editable Code -> 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: /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