Anticipatory Response Inhibition Task - ARIT

Technical Manual

Script Author: Hall, A., Weightman, M., Jenkinson, N., & MacDonald, H. J.

Credits:
Millisecond thanks Dr. H. MacDonald for sharing the original Inquisit ARIT script!
The script was updated to Inquisit7 by K. Borchert, Millisecond.
The original Inquisit script (Inquisit6) can be requested from the original authors.

The script was updated to Inquisit7 by K. Borchert, Millisecond.
The original Inquisit script (Inquisit6) can be requested from the original authors.

Last Modified: January 23, 2025 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements the Anticipatory Response Inhibition Task (ARIT, Hall et al 2023); a variant of the Stop Signal Task with an anticipatory response component to measure a person's inhibition ability.

References

Hall, A., Weightman, M., Jenkinson, N., & MacDonald, H. J. (2023). Performance on the balloon analogue risk task and anticipatory response inhibition task is associated with severity of impulse control behaviours in people with Parkinson’s disease. Experimental Brain Research, 241(4), 1159–1172. https://doi.org/10.1007/s00221-023-06584-y

Duration

45 minutes

Description

Participants see two empty bars; one on the left and one on the right. Each trial is started by participants pressing down on a left response key (here: "z") and a right response key (here: "?"). Once both response keys are pressed down, both bars start rising.

The basic GO-task is to lift both fingers once the bars reach a visible target threshold.

In some trials, however, the bars stop rising before they reach the target threshold. In these 'STOP' trials, the potentially initiated go-response (= lifting finger) needs to be stopped. This is hardest when the STOP signal (= bars stop rising) happens very close to the target threshold.

There are four different trial types:

Go Trials: no stop signal (that is the bar never stops growing); participants should lift fingers when bars reach the target threshold stopBoth Trials: both bars stop; participants should NOT lift fingers until the end of the trial (when feedback is provided) stopLeft Trials: only the LEFT bar stops; participants should NOT lift their left finger but should still try to lift the right finger at target threshold. stopRight Trials: only the RIGHT bar stops; participants should NOT lift their right finger but should still try to lift the left finger at target threshold.

In the stopSignal trials, the SSD (stop signal delay) is constantly updated. For correct responses: the SSD increases (which will make the task harder) For error responses: the SSD decreases (which will make the task easier)

Procedure

1. Instruction And Practice Block:
All conditions (go, stopBoth, stopLeft, stopRight) are explained with videos

a. Go Trials: try to lift both fingers when the rising bar hits the target line
=> 20 practice trials

b. StopBoth Trials: Rising bar will stop before it reaches the target line; don't lift your fingers until the end
=> 3 practice trials

c. StopLeft Trials: Rising bar will stop for the LEFT only. Keep left finger on the key for the entire trial BUT try to lift the RIGHT finger when the bar hits the target line.
=> 3 practice trials

d. StopRight Trials: Rising bar will stop for the RIGHT only. Keep right finger on the key for the entire trial BUT try to lift the LEFT finger when the bar hits the target line.
=> 3 practice trials

2. Test
- 10 experimental blocks of 40 trials each
=> across the 10 blocks: 295 go-trials; 35 stopBoth trials; 35 stopLeft trials; 35 stopRight trials
=> the trials are run in a fixed order

Stop Signal Delay (Ssd)
- The SSD in this script is the time that the bar(s) stop(s) rising (=> a stopping bar is the Stop Signal)
=> the closer the rising bar gets to the target line, the more difficult it will be to stop the initiated go
response (aka lifting finger off when the rising bar hits the target line)

- The SSD is adjusted independently for BOTH, LEFT, and RIGHT stop trials

The SSD adjustment algorithm used in this script is as follows:
correct response: SSD gets increased by 25ms (editable parameters) -> MAX SSD in this script: 750ms (see expressions.maxSsd)
error response: SSD gets decreased by 25ms (editable parameters) -> MIN SSD in this script: 50ms (see parameters.minSsd)
(see Definition of 'acc' under raw data column for how responses are classified as correct/error responses in this script)

Stimuli

generated by script

Instructions

provided by original script - can be edited in script arit_instructions_inc.iqjs

Summary Data

File Name: arit_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
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
totalRiseDurationMS Parameter: the time (in ms) it takes for the entire box to fill (also the trialduration)
goGoalRT Stores the theoretical goal GO response time (in ms) that would hit the target perfectly (80% of the totalRiseDuration)
stopBothAccOverall Mean percent correct Responses in stopBoth trials
stopLeftAccOverall Mean percent correct Responses in stopLeft trials
stopRightAccOverall Mean percent correct Responses in stopRight trials
meanGoRT Mean Go response time (in ms) in go Trials
here: calculated as the ('weighted') mean of all left and right response times in go Trials
meanStopBothRT Mean (error) response time (in ms) in stopBoth trials
here: calculated as the ('weighted') mean of all left and right response times in stopBoth Trials
Note that this approach might overestimate the mean response time. It was used to keep it comparable
to meanGoRT.
An alternative approach could be to only look at the FIRST response time in stopBoth trials.
meanSSDStopBoth Mean SSD (in ms) in stopBoth trials
ssrtIntegration The primary DV: the covert stop signal response time (SSRT) in stopBoth trials, calculated using the
Integration Method suggested by Verbruggen et al (2019).
The SSRT is the time required to stop the initiated go-process and is considered a measure of inhibition ability.
Disclaimer: this variable and its calculations were added by Millisecond
they were not part of the original script.
The algorithm summarized in short
- order go RTs from smallest to largest (=> fastest to slowest RT)
replacing all noResponse RTs with the maximum observed GoRT (=values.maxGoRT)
- determine the Go Response Time that corresponds to the probability of responding in stopBoth trials (=values.nthRT)
- calculate SSRT = values.nthRt - meanSSD
pRBoth Probability for responding in stopBoth trials (in %); debugging variables for ssrtIntegration Calculation
nth The index in list of go RTs that corresponds to the probability of responding in stopBoth trials; debugging variables for ssrtIntegration Calculation
nthRT The RT in the ORDERED list of go RTs that corresponds to the probability of responding in stopBoth trials; debugging variables for ssrtIntegration Calculation
maxGoRT The max. RT of actual responding in go trials; debugging variables for ssrtIntegration Calculation
goRTTotal Number of RTs in go trials ; debugging variables for ssrtIntegration Calculation

Raw Data

File Name: arit_raw*.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
blockcode The name the current block (built-in Inquisit variable)
blocknum The number of the current block (built-in Inquisit variable)
trialcode The name of the currently recorded trial (built-in Inquisit variable)
trialnum The number of the currently recorded trial (built-in Inquisit variable)
trialnum is a built-in Inquisit variable; it counts all trials run
even those that do not store data to the data file.
blockCounter Tracks the number of blocks run
trialCounterPerBlock Tracks the number of trials run per block
phase "practice" vs. "experimental"
trialType "na" (go), "both", "left", "right"
ssd The current stop signal delay (ssd)
SSDs for both, left, right trials are tracked independently from each other
totalRiseDurationMS The time (in ms) it takes for the entire box to fill (also the trialduration)
goGoalRT Stores the theoretical goal GO response time (in ms) that would hit the target perfectly (80% of the totalRiseDuration)
leftKeyLiftTime The response time (in ms) for lifting the left finger
rightKeyLiftTime The response time (in ms) for lifting the right finger
success 0 = failure
1 = stop failure (=> finger lift) but target hit (applies to 'left' and 'right' trials only)
successes: considered as correct responses
2 = stop success (=> finger stays put) but target miss (applies to 'left' and 'right' trials only)
3 = complete success
acc 0 = overall the response pattern is considered an error
go trial: one or both fingers were not lifted around target line
stopBoth: at least one finger was lifted before end of trial
stopLeft/stopRight: a) no finger as lifted
b) the left (right) finger was lifted for stopLeft (for stopRight) trials
1 = overall the response pattern is considered correct
go trial: both fingers lifted around target line
stopBoth: no finger was lifted before end of trial
stopLeft/stopRight: the left (right) finger was not lifted; the right (left) finger was lifted before end of trial (target hitting/missing irrelevant for accuracy)
ssdBoth The value of the last adjusted ssdBoth (should be used for next stopBoth trial) - for debugging purposes
ssdLeft The value of the last adjusted ssdLeft (should be used for next stopLeft trial) - for debugging purposes
ssdRight The value of the last adjusted ssdRight (should be used for next stopRight trial) - for debugging purposes

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
Sizing Parameters
barWidthPct The percentage width of the bar (relative to canvasWidth)5%
totalBarHeightPct The percentage height of the bar (relative to canvasHeight)50%
targetLocationPct The target location should be at 80% of the bar height
=> the targetLocation should be reached in totalRiseDurationMS*0.8 => 800ms
80%
Timing Parameters
totalRiseDurationMS Time (in ms) it takes to reach the top of the bar1000
targetToleranceBelowMS Minimum accepted RT (in ms) to have reached target: goGoalRT - targetToleranceBelowMS30
targetToleranceAboveMS Maximum accepted RT (in ms) to have reached target: goGoalRT + targetToleranceAboveMS
goGoalRT (depends on totalRiseDurationMS) = time (in ms) it would take to reach targetLocationPct (80% of 1000ms = 800ms)
40
countdownTimerMS Countdown duration in ms CHANGE!!!20000
feedbackDurationMS Feedback duration in ms2000
Staircase Procedure
initialStopTimeBoth Initial stop duration (in ms) in bothStop trials600
initialStopTimeLeft Initial stop duration (in ms) in leftStop trials600
initialStopTimeRight Initial stop duration (in ms) in rightStop trials600
staircaseIncrement Ms adjustment for staircase changes25
minSsd The minimum Stop Signal Delay (in ms)
see expressions.maxSsd below for calculation of the maxSSd
50
Response Keys
responseKeyLeftDown Scancode for left letter Z44
responseKeyLeftUp Negative scancode for left letter Z-> take finger of Z-44
responseKeyRightDown Scancode for "?"53
responseKeyRightUp Negative scancode for "?"-> take finger of "?"-53
responseKeyLeftLabel The response key labels used in instructions"[ Z ]"
responseKeyRightLabel The response key labels used in instructions
the response keys assume a QWERTY keyboard
changes in responsekeys necessitates changes to the instruction (videos)
"[ ? ]"