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				AUDITORY STROOP FOR ACOUSTIC DIMENSIONS (Pitch, Loudness, Duration)
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-23-2014
last updated: 08-15-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Script Copyright © 08-15-2016 Millisecond Software


BACKGROUND INFO

										*Purpose*
This script runs the auditory Stroop (pitch, loudness, duration) described by:

Morgan, A.A.R. & Brandt, J.F. (1989). An Auditory Stroop Effect for Pitch, Loudness, and Time.
BRAIN AND LANGUAGE 36, 592-603.

										 *Task*
Participants hear Stroop and Non-Stroop words of 3 different acoustic dimensions (pitch, loudness, duration).
Stroop Words: words that are related to the acoustic dimension (e.g. pitch: low)
Non-Stroop Words: words that are neutral in relation to the acoustic dimensions (e.g. cat)
Depending on the acoustic dimension tested, they have to make categorical judgments and sort the word
into one of 2 categories as fast as possible.
Example: they hear 'cat' in a low-pitched voice and are asked to either press the response key dedicated to 
'low' or press the response key dedicated to 'high'.


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

(1) Raw data file: 'AuditoryStroop_AcousticDimensions_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 
/session_nr:					number of current session
/Earcondition:					1 = right ear is tested; 2 = left ear is tested

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) 
/dimension:						1 = pitch; 2 = loudness; 3 = duration; 4 = control_pitch; 5 = control_loudness; 6 = control_duration
/level:							1 = high/loud/long; 2 = low/SOFT/short; 3 = neutral
/congruence:					0 = neutral/control; 1 = congruent; 2 = incongruent
/volume:						stores the current word volume
/selecteditemnumber:			stores the actual itemnumber of the current stimulus (e.g. item 5 of level HIGH -> itemnumber: 11 of item.pitchwords)
stimulusitem:					the presented stimuli in order of trial presentation
response:						the participant's response (scancode of response key)
/response:						"high" vs. "low", "loud" vs. "SOFT", "long" vs. "short"
correct:						the correctness of the response (1 = correct; 0 = incorrect)
									Note: by design accuracy of response of "neutral stimuli" (level3 stimuli) is always set to 1 in this script
latency: 						the response latency (in ms)


block.practice.sdlatency:		stores the calculated standard deviation of the response latencies of the current practice block trial-by-trial
block.practice.meanlatency:		stores the calculated mean response latency of the current practice block trial-by-trial

(2) Summary data file: 'AuditoryStroop_AcousticDimensions_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)
/session_nr:					number of current session
/Earcondition:					1 = right ear is tested; 2 = left ear is tested; 3 = dual channels
/propcorr_C_P:					proportion correct congruent pitch trials
/propcorr_IC_P:					proportion correct incongruent pitch trials
/meanRT_C_P:					mean RT (in ms) of correct congruent pitch trials
/meanRT_IC_P:					mean RT (in ms) of correct incongruent pitch trials
/meanRT_N_P:					mean RT (in ms) of neutral pitch trials
(same for loudness (L)  and duration (D))

/propcorr_ctrlP:				proportion correct comparison control pitch trials
/meanRT_C_ctrlP:				mean RT (in ms) of correct comparison control pitch trials
									!NOTE: comparison control trials = level 1 and level 2 (excluding the neutral stimuli)
/meanRT_N_ctrlP:				mean RT (in ms) of neutral (level3) control pitch trials
							(same for control loudness and control duration)



EXPERIMENTAL SET-UP
2 ears (left, right): tested within-subject, blocked design (different sessions -> parameters.session_nr can be set under Editable Values)
6 acoustic dimensions (pitch/pitchcontrol, loudness/loudnesscontrol, duration/durationcontrol): tested within-subject, mixed design
	!!!NOTE: if the acoustic dimensions (pitch/loudness/duration) should be tested in a blocked-design, go to 
	section EXPERIMENT and follow instructions
3 levels per acoustic dimension (e.g. pitch: low, high, neutral): tested within-subject, mixed design
6 stimuli per acoustic dimension
3 repetitions per stimuli
Stimulus Onset Asynchrony: 5s => soundfiles are presented 5s apart (Editable Parameters)

=> 2 sessions x 6 acoustic dimensions x 3 levels x 6 stimuli x 3 repetitions = 2 x 324 trials

Ear condition: parameters.Earcondition (Editable Parameters) sets whether the stimuli are presented through one ear (left or right)
as done by Morgan & Brandt (1989) or both ears at the same time.

Response key assignments to left or right: by default the left and right response keys are the 'A' and 'L' keys (change under Editable Parameters)
Assignment of low-high, soft-loud, short-long response keys to the left and right response key (2 possible orders) is counterbalanced 
by odd vs. even groupnumber (See section EXPERIMENT for more info)

Blocks:
Training
(1) Stabilization: participants are asked to respond randomly with the left and right response keys to various beeps (108 trials)
(2) Familiarization: participants are presented all experimental stimuli but no response is required. The presentation
stream can be paused in this script and the last stimuli repeated.
!!!Note: parameters.run_stabilization/parameters.run_familiarization (Editable values) control if these blocks are run.
If parameters.session_nr > 1, these values are automatically set to false (and these training blocks are skipped)

(3) Practice: participants are asked to respond to a block of 12 randomly selected experimental stimuli by pushing the response button that 
corresponds to the instructions (e.g. LEFT/RIGHT) on the screen. LEFT/RIGHT instructions are randomly selected without replacement.
Participants have to hit a certain criterium to move from practice otherwise another block of 12 trials is started.

Criterium to quit practice: 
If the standard deviation of the response latencies of those 12 trials < 50% of the mean latency of those 12 trials (Morgan & Brandt, 1989, p.597)

Experimental Block:
(4) 324 trials: runs all 54 possible trials of each acoustic dimension (6 acoustic dimensions)
(54 => 3 levels x 6 stimuli per level x 3 repetitions per stimuli)

!Note: the semi-random order of the 324 trials is generated before each session by 
included helper script 'stimordergeneration.iqx' with the following constraints:
the same dimension (pitch, loudness, duration, control) cannot be run consecutively
(this includes not running a pitched control word after a pitched stroop word etc.)

STIMULI
The provided sound files are not original to Morgan & Brandt (1989). They are provided by Millisecond Software.
All recordings by a male native speaker of American English.
Pitch & Duration were manipulated in Audacity.
Volume is manipulated by script itself
(neutral volume is set to be at -1000 for all conditions; loud is set to be at 0; and soft is set to be at -2000 - editable values)

Stimuli can be exchanged under section Editable Stimuli

INSTRUCTIONS
The provided instructions are not original to Morgan & Brandt (1989). They are provided by Millisecond Software.
The instructions are presented in the form of html pages. To change the instructions, edit the corresponding
html files.

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:

/responsekeyleft:						scancode of the left response key
											Note: scancodes under Tools -> Keyboard Scancodes (default: 30)
/responsekeyleft_label:					label of the left response key (default: "A", A has scancode 30)
/responsekeyright:						scancode of the right response key (default: 38)
/responsekeyright_label:				label of the right response key (default: "L", L has scancode 38)

/session_nr:							number of current session
/Earcondition:							1 = right ear is tested; 2 = left ear is tested; 3 = dual channels

/familiarization_duration:				duration of the stimuli presentations during familiarization trials (default: 2000ms)


/run_Stabilization:						true: runs the stabilization procedure 
										false: does not run the stabilization procedure => might have to update default instructions

/run_familiarization:					true: runs the familiarization procedure
										false: does not run the familiarization procedure => might have to update default instructions
										Note: if parameters.session_nr = 2; parameters.run_Stabilization and parameters.run_familiarization are set to fault automatically

/soa:									stimulus onset asynchrony: time between onset of one stimulus and the onset of the next
										in ms (default: 5000) -> every 5 s a new word is spoken.

Volume Adjustment:
/loudvolume:							volume setting for the loud volume (default: 0)
											Note: a setting of 0 plays the sound file at the recorded volume (0 is the max setting)
/neutralvolume:							volume setting for all neutral sound files (default: -1000)
											Note: a slight volume reduction
/softvolume:							volume setting for all soft sound files (default: -2000)

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