Choice Reaction Time Test - Touchscreen

Technical Manual

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond

Created: January 17, 2018

Last Modified: January 13, 2025 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements a Choice Reaction Time Task for the touchscreen.

Duration

2 minutes

Description

Choice Reaction Time Task: press a home button that is presented within the half circle of 5 possible response buttons until one of the response buttons turns yellow, then click the yellow response button as fast as possible

The Choice Reaction Time Task tracks the durations participants spent on various subtasks: 1. time spent on homeButton 2. time between onset of target stimulus and lifting finger off homeButton (A) 3. time between lifting finger off homeButton and pressing down on target stimulus (B) 4. time spent on target stimulus (C) 5. time between lifting finger off target stimulus and pressing down on homeButton (D)

The stimuli in this script can be sized absolutely so that distances btw. buttons are the same on each monitor. To do so, go to section Defaults for more information.

By default, this script uses proportional sizing; using 100% of the available screen height and screen width = 4/3 * screen height (width:height: 4:3)

Procedure

1. Intro with a demo: runs 2 demo trials for each participant regardless of performance

2. Practice:
- max. 10 trials
- Pass Criteria: 5 correct trials in a row (correct = finger lifts off home button after square appears and presses down on square within 5000ms)

3. Test: 20 trials (default; each response button runs 4 times)
- 4 isi (see list.isiChoiceRT: 1000ms, 3000, 2000ms, 4000ms), selected randomly

Instructions

provided in script "choicereactiontimetask_touchscreen_instructions_inc.iqjs"

Summary Data

File Name: choicereactiontimetask_touchscreen_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
startDate Date the session was run
startTime Time the session was run
subjectId Participant ID
groupId Group number
sessionId Session number
elapsedTime Session duration in ms
completed 0 = Test was not completed
1 = Test was completed
choiceRTDuration Stores the duration (in ms) of the choice RT task (only test session; excludes demo & practice)
practicePassChoiceRT 0 = participant did not pass practice criteria for choiceRT
1 = participant passed practice criteria for choiceRT
meanRTChoiceRT Mean latency (in ms) of pressing down on stim (latency measured from onset of target to
pressing down on it); only correct responses
accChoiceRT Mean proportion correct (correct = target square was hit as opposed to elsewhere or no response)
totalEarlyResponsesChoiceRT Counts premature lift-offs (off homebutton) across all test trials in the choiceRT task
only for responses with finalAcc = 1
meanDurationA Mean duration (in ms) btw. onset of target button (stimPresentTime) and lifting finger off home button
meanDurationB Mean duration (in ms) btw taking finger off Home Button and pressing down on Stim Button
meanDurationC Mean duration (in ms) finger spent on Stim Button
meanDurationD Mean duration (in ms) btw taking finger off Stim Button and pressing down again on Home Button
meanDurationHomeButton Mean duration (in ms) finger spent on homeButton

Raw Data

File Name: choicereactiontimetask_touchscreenRaw*.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
blockCode Name of the current block
blockNum Number of the current block
trialCode Name of the current trial
trialNum Number of the current trial
list.practiceCorrect.mean Stores the proportion correct of the last 5 responses during the current practice session
practicePass 0 = participant did not pass practice criteria
1 = participant passed practice criteria
trialCount Counts all trials (trial = current trial sequence) in a block
isi Current interstimulus interval in ms
targetPosition Response square 1-5
responseArea Stores the response area clicked
choice Reaction Time Task: 'target button' vs. 'elsewhere' vs. " " (did not respond during response window)
acc 1=correct/right stimulus,
2="elsewhere" i.e. outside the stimulus
3 = no response
finalAcc Stores final correctness of response (1 = correct; 0 = incorrect)
choice Reaction Time Task: correct = target is pressed
rt Response time (in ms) from onset of Stim until the stim is pressed
(rt is empty if the stim is not pressed)
rtDown1 Script.elapsedTime (in ms) of clicking home-button (measured relative to start of script in ms)
! if finger lifts off home button prior to Stim appearance,
rtDown1 resets to the moment the finger returns to the home button
and isi is restarted from that moment.
rtUp1 Script.elapsedTime (in ms) of lifting finger off home-button (measured relative to start of script in ms)
rtUp1 is measured AFTER Stim appearance
rtDown2 Script.elapsedTime (in ms) of clicking stim-button or 'elsewhere' (measured relative to start of script in ms)
rtUp2 Script.elapsedTime (in ms) of lifting finger off stim-button or 'elsewhere' (measured relative to start of script in ms)
rtDown3 Script.elapsedTime (in ms) of clicking home-button after lifting finger off stim-button (measured relative to start of script in ms)
if participants stays on home button until stim appears
rtDown3 is assigned rtDown1 of the next trial
stimPresentTime Timestamp of target square (measured relative to start of script in ms)
the time (in ms) measured from start of script until this target appeared on screen
a Time (in ms) btw. onset of target button (stimPresentTime) and lifting finger off home button (rtUp1)
b Time (in ms) btw taking finger off Home Button and pressing down on Stim Button
c Time (in ms) finger spends on Stim Button (pressing down on stimulus to lifting off stimulus)
d Time (in ms) btw taking finger off Stim Button and pressing down again on Home Button
durationHomeButton Time (in ms) finger spent on homeButton
countEarlyResponses Counts premature lift-offs (off homebutton) during the current trial
totalEarlyResponses Counts premature lift-offs (off homebutton) across all test trials

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
Design Parameters
button1ChoiceRT True (default) = button 1 (left button) is presented; false = button 1 not presentedtrue
button2ChoiceRT True (default) = button 2 is presented; false = button 2 not presentedtrue
button3ChoiceRT True (default) = button 3 (center button) is presented; false = button 3 not presentedtrue
button4ChoiceRT True (default) = button 4 is presented; false = button 4 not presentedtrue
button5ChoiceRT True (default) = button 5 (right button) is presented; false = button 5 not presentedtrue
numberTestTrials The number of test trials run
needs to be divisible by the number of presented responseButtons (responseaquares)
20
presentFinalRTFeedback True (1): participants receive feedback about their average (correct) reaction time
at test termination (default)
false (0): no reaction time feedback is provided at the end
true
Color Parameter
canvasColor Display color of the actively used portion of the screen (the 'canvas')
if set to a color other than the screenColor, you can distinguish the active canvas
from the inactive portion of the screen
lightGray
screenColor Color of the screen not used by the canvas ('inactive screen')lightGray
defaultTextColor Default color of text itemsblack
Sizing Parameters
homeButtonSize The proportional size of the Home Button (relative to canvas) 15%
responseButtonSize The proportional size of the response squares (relative to canvas) 15%
homeButtonChoiceRTY The vertical position of the homeButton in the choice Reaction Time Task in canvas height% 50%
circleProportion Proportion of canvas height used for the circle radius of response buttons in choice Reaction Time Task 0.3
Timing Parameters
feedback Presents feedback 2000
homeButtonRW Home button response window until a reminder is flashed onto the screen
the trial continues until the home button is pressed
6000
stimRW Response window after stim is presented 6000