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									REDUNDANT SIGNAL TASK (RST)
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-02-2013
last updated: 01-25-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 01-25-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements the Redundant Signal Task as described in:

Mark T. Fillmore, M.T. (2010). Processing Bimodal Stimulus Information Under Alcohol: Is There a Risk to Being Redundant?
Experimental and Clinical Psychopharmacology, 18, 429–435.

											  *Task*
Participants perform a simple categorization task on 2 letters and/or 2 tones. The letters and/or tones
are presented at three random time intervals after a fixation cross disappears from the screen. Participants are 
asked to press one key for letter1/tone1 (here: O and high tone) and another key for letter2/tone2 (here: X and low tone).
There are 3 blocks: one block presents only the letters, one block presents only the tones, and one
block presents letters and tones simultaneously ("redundant" condition).


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

(1) Raw data file: 'RedundantSignalTask_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) 
/practice:						0 = test trials; 1 = practice trials;
/SOA:							current SOA
/target:						1 = 0 and/or high tone; 2 = X and/or low tone
response:						the participant's response (scancode) (Note: 0 means trial timed out without a response)
correct:						the correctness of the response
latency: 						the response latency (in ms)
/valid:							1 = valid (latencies in acceptable range); 0 = invalid (latencies outside acceptable range)
/countinvalidtrials:			sums up the number of invalid trials
/countvalid_visualonly-
/countvalid_redundant:			count the number of valid trials in each condition
/countcorrect_visualonly-
/countcorrect_redundant:		count the number correct responses (for valid trials only) in each condition
/sumrt_visualonly -
/sumrt_redundant:				sums up the latencies for correct responses (for valid trials only) in each condition

(2) Summary data file: 'RedundantSignalTask_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)
/meanrt_visualonly -
/meanrt_redundant:				mean latency of correct responses (valid trials only) for the different condition (in ms)

/correctprop_visual -
/correctprop_redundant:			proportion of correct responses (valid trials only) for the different conditions

/percentinvalid:				percent invalid trials (latencies outside specified boundaries)



EXPERIMENTAL SET-UP:
type of stimuli presented (visual only vs. audio only vs. both) tested within subjects in a blocked design

* Experimental Blocks:
- 3 blocks, order counterbalanced (latin square) by groupnumber 1-3
- 90 trials per block
- targets (e.g. O vs. X) randomly determined (=> 1/2 the trials with 0)

* Trial Sequence:
- Fixation cross (250ms) -> white screen (random SOA duration) -> target (response terminated of maximum presentation of 1000ms)-> ITI (2000ms)
- SOA is randomly determined. By default in this script: frequency of SOAs fixed at 1/3 for each of the 3 SOAs (=> see list.soas)
- pairings of letter and sound the same for all: O and high tone vs. X and low tone

* Practice:
- 3 practice blocks of 20 trials each (order always: visual -> audio -> redundant)
- errorfeedback

STIMULI
* visual: X vs. O
* audio: low tone (125Hz) vs. high tone (1000Hz); provided sound files were generated in Audacity, length: 5s, Amplitude: 0.8
see section Editable Stimuli

INSTRUCTIONS
Instructions are not original can be edited under 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:

Appearance of visual target:
/fontheight:								size of font (percentage of screen height) (default: 15%)

Appearance of audio target:
/volume_hightone:							volume adjustment for the high tone (default: -2000)
/volume_lowtone:							volume adjustment for the low tone (default: 0)


Durations:
/fixationcrossduration:						duration of fixation cross in ms (default: 250ms)
/maxtargetduration:							max duration that target is on screen in ms (default: 1000ms)
											Note: if no response is given, trial expires after presenting the target for parameters.maxtargetduration
/iti:										intertrialinterval in ms (default: 2000ms)

Responsekeys
/responsekey1:								scancode of responsekey 1 (default: 30)
/responsekey1_label:						label of responsekey 1 (default: "A")
/responsekey2:								scancode of responsekey 2 (default: 38)
/responsekey2_label = "L"					label of responsekey 2 (default: "L")
											Note: scancodes can be obtained via Tools->Keyboard Scancodes


/minRT:										minimum acceptable response latency in ms (default: 100ms)
/maxRT:										maximum acceptable response latency in ms (default: 1000ms)
											Note: outside these boundaries, the responses are counted as invalid trials

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