Return to the Simple Auditory Reaction Time Task (Keyboad Input) page
___________________________________________________________________________________________________________________	

							*Simple Auditory Reaction Time Task (Keyboad Input)*
___________________________________________________________________________________________________________________

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 06-04-2018
last updated:  03-11-2020 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 03-11-2020 Millisecond Software

___________________________________________________________________________________________________________________
BACKGROUND INFO 	
___________________________________________________________________________________________________________________	
This script implements a Simple Auditory Reaction Time Task loosely based on:

Fry, D.B. (1975). Simple Reaction-Times to Speech and Non-Speech Stimuli.
Cortex, 11, 355-360.

Note: the original study was conducted with tape recorders. This script
adapts the original procedure to the computer. Voice responses are
omitted in this script.

___________________________________________________________________________________________________________________
TASK DESCRIPTION	
___________________________________________________________________________________________________________________	

Participants hear two different sounds and are asked to respond to the sounds by pressing the spacebar

By default, the sounds are tested in a mixed design (can be changed to a blocked design under
section Editable Parameters)

___________________________________________________________________________________________________________________	
DURATION 
___________________________________________________________________________________________________________________	
the default set-up of the script takes appr. 5 minutes to complete

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

(1) Raw data file: 'simpleauditoryreactiontimetask_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.countTestBlocks:				counts the number of test blocks run									
values.blocktrialcount:				custom variable to count the trials run in a given block
values.countValidBlockResponses:	counts the number of valid responses per block (valid = response started after onset of stim)
values.phase:							"practice" vs. "pretest" (the first 5 trials in each test block) vs. "test"
									
values.sound:						1 = sound1 (here: 'a'); 
									2 = sound2 (here: telephone ring)
									
values.delay:						stores the randomly selected sound delay (in ms) - relative to onset of trial								
																		
response:							the participant's response (57 = spacebar press)
correct:							accuracy of response (1 = correct; 0 = otherwise)
latency: 							the response latency (in ms); measured from: onset of trial (NOT onset of sound), see 'Sound RT' below

values.trialTimestamp:				the script elapsedtime (in ms; measured from script start) of the current trial onset
sound.tone.timestamp:				the script elapsedtime (in ms; measured from script start) of the last presented sound onset
										Note: if the tone has not been played yet, the variable contains a randomly selected number

values.RT_timestamp:				the elapsedtime of the current response relative to start of script (in ms)
										Note: calculated as timestamp of trial onset + latency; timestamp of trial is measured from start 
										of script, latency is measured from start of trial
										
values.RT_stimonset:				the elapsed time of the current response relative to onset of sound stim (= RESPONSE TIME TO SOUND; in ms)
										(when the sound stim timestamp is still the same as the one from the previous trial at time of response, 
										Sound RT = "Early Response" as no new sound has been played yet)
										Note: calculated as the difference from 'values.RT_timestamp - timestamp of sound onset' (both are measured from onset of script)

										
(2) Summary data file: 'simpleauditoryreactiontimetask_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)

expressions.testtrials_total: 			total number of test trials run (across blocks)
expressions.countEarlyResponses_total: 	total number of early responses (across blocks)
expressions.propEarlyResponses_total: 	proportion early responses across all test trials

Note: 
early responses are excluded from mean/standard deviation calculations.
Only responses that were recorded AFTER the onset of the sound stimulus are considered for mean and standard deviation calculations

expressions.testtrials_sound1: 			calculates number of test trials run in Sound1  condition
expressions.meanRT_sound1:				mean response latency (in ms) to the sound stimulus in Sound1 condition (here: space bar press to 'a')
expressions.SD_sound1:					standard deviation of response latencies (in ms) in Sound1 condition
values.countEarlyResp_sound1:			counts all "early responses" (responses BEFORE sound onset) in sound1  condition
expressions.propEarlyResponses_sound1: 	proportion early responses of all test trials run in Sound1 condition (here: space bar press to 'a')

expressions.testtrials_sound2: 			calculates number of test trials run in Sound2  condition
expressions.meanRT_sound2:				mean response latency (in ms) to the sound stimulus in Sound2 condition (here: space bar press to 'telephone ring')
expressions.SD_sound2:					standard deviation of response latencies (in ms) in Sound2 condition
values.countEarlyResp_sound2:			counts all "early responses" (responses BEFORE sound onset) in Sound2  condition
expressions.propEarlyResponses_sound2: 	proportion early responses of all test trials run in Sound2 condition (here: space bar press to 'telephone ring')


* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions

___________________________________________________________________________________________________________________	
EXPERIMENTAL SET-UP 
___________________________________________________________________________________________________________________	
Default Design: 2 different sounds are tested in a within participant,mixed design:
(can be changed to a blocked design; see section Editable Parameters)

Mixed Design Option:
10+ Practice Trials:
- minimum of 5 practice trials per sound
- sound order is randomly determined

50 + Test Trials
- minimum of 25 test trials per sound (If parameters.repeatEarlyResponseTrials is set to 'true' then the 'early response' 
trials get repeated at the end of the block and thus there will be 25 valid test trials per sound at script conclusion)
- sound order is randomly determined

Blocked Design Option:

Per block:
10+ Practice Trials:
- minimum of 10 practice trials (no repeats of incorrect practice trials)

25 + Test Trials
- minimum of 25 test trials (If parameters.repeatEarlyResponseTrials is set to 'true' then the 'early response' 
trials get repeated at the end of the block and thus there will be 25 valid test trials per sound at script conclusion)

Sound Delays:
at the beginning of each sound trial, a sound delay is randomly sampled (with replacement) from list.delay
Delays: 2400ms-3700ms with increments of 100ms (change delays under section Editable Lists)

___________________________________________________________________________________________________________________	
STIMULI
___________________________________________________________________________________________________________________	
sound file for the letter 'a' from: http://soundbible.com/2009-A-Z-Vocalized.html#A-Z%20Vocalized%20Sound
sound file for telephone ring from: http://free-mobi.org/ringtones/sound-effects/telephone-ring

both sound files were cut to 450ms and their peak amplitude set at 1.0dB by Millisecond Software
in Audacity.
___________________________________________________________________________________________________________________	
INSTRUCTIONS 
___________________________________________________________________________________________________________________	
provided by Millisecond Software
all text stimuli 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:

/readyDuration:						the default duration (in ms) of the get-ready trial (default: 2000ms)
/earlyResponseFeedback:				the duration (in ms) of the "Early Response" Feedback (default: 1000ms)

/repeatEarlyResponseTrials:			true (1) = early response trials get immediately repeated (default)
										=> at conclusion of script, there are 30 valid response measures in all 4 blocks
										false (0) = early response trials do not get repeated
									
/showRTfeedback:					true (1) = response time feedback is provided for valid responses (default)
										false (0) = no response time feedback is provided 
									
/RTfeedbackDuration:				duration (in ms) of response time feedback (default: 500ms)
										Note: the response time feedback adds additional 500ms to the task for each trial
																	
/mixedDesign:						true (default)= the 2 sound stimuli are presented within the same block
									false = the 2 sound stimuli are tested within a blocked design