Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 28, 2018
Last Modified: January 09, 2026 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements an short arrow version of the Flanker Test, an inhibition test to assess the ability to suppress inappropriate dominant responses evoked by task irrelevant information. The script was written for use on tablets (e.g. ipads). A version for smartphone use (e.g. remote testing) is also available through the Millisecond library.
The implemented version is generously shared by the ABCD Consortium.
3 minutes
Participants see 5 arrows in the middle of the screen inside a box. They have to decide whether the central arrow points right or left. The surrounding arrows (=flankers) either point in the same direction (congruent trials) or in the opposite direction (incongruent trials).
2 flanker congruence (congruent vs. incongruent), tested within
1-3 Practice Blocks: each block runs 4 trials with errorfeedback (number of trials can be edited under section Editable Parameters)
- participants have to get 75% correct to move on to the test block (proportion correct editable under section Editable Parameters)
- after 3 failed practice runs, all participants move on to the test
- trial order is fixed; fixation star duration = 1250ms for each trial
1 Test Block: runs 20 trials in fixed sequence
Trial Sequence:
homeBase (waits for finger to press homeBase)
-> presents fixation star for values.fixationDuration (1000, 1250, 1500ms)
-> presents 'middle' text reminder (default: 100ms)
-> presents flankers (default: 100ms)
-> adds the target and waits for response
the selected response button is highlighted for 100ms
-> homeBase for 800ms (whether pressed or not)
stimuli: 5 arrows pointing right or left (flanker, flanker, target, flanker, flanker)
Arrows can be edited under section Editable Stimuli
Instructions are similar to the NIH toolbox Arrow Flanker Test.
Instruction text can be edited under section Editable Instructions
File Name: abcdshortarrowflankertest_touchscreen_summary*.iqdat
| Name | Description |
|---|---|
| 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 |
| blockCounter | Number of test blocks run |
| countPracticeBlocks | Counts the number of practice runs |
| list.accPractice.mean | The proportion correct at the end of the last practice run |
| practicePass | 1 = participant passed practice 0 = participant did not pass practice |
| trialCounter | Overall trial count |
| propCorrect | Overall proportion correct (test trials only) |
| meanRT | Overall mean latency (in ms) of correct responses (test trials only) |
| medianrt | Overall median latency (in ms) of correct responses (test trials only) |
| trialCounterCongruent | Congruent trial count |
| propCorrectCongruent | Proportion correct for all congruent trials |
| meanrtCongruent | Mean latency (ms) of correct responses to congruent targets |
| medianrtCongruent | Median latency (ms) of correct responses to congruent targets |
| trialCounterIncongruent | Incongruent trial count |
| propCorrectIncongruent | Proportion correct for all incongruent trials |
| meanrtIncongruent | Mean latency (ms) of correct responses to incongruent targets |
| medianrtIncongruent | Median latency (ms) of correct responses to incongruent targets |
File Name: abcdarrowflankertest_touchscreen_raw*.iqdat
| Name | Description |
|---|---|
| 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. |
| practice | 0 = test block; 1 = practice block |
| blockCounter | Counts the test blocks run |
| countPracticeBlocks | Counts the number of practice runs |
| trialCounter | Counts all trials per block |
| congruence | Determines the state of the flankers 1 = congruent (target and flanker point in the same direction), 2 = incongruent (target points in opposite direction) |
| selectTarget | Itemnumber of the current target (center) stimulus 1 = target points to right 2 = target points to left |
| selectFlanker | Itemnumber of the current flanker stimuli |
| response | The participant's response (leftResponseButton, rightResponseButton) |
| correct | The correctness of the response (0 = error or no response; 1 = correct) |
| latency | The response latency (in ms); measured from onset of target to response (or trial timeout) |
| homeButtonRT | The response time to press the homeButton during trial.homeBase |
| list.accPractice.mean | The current proportion correct at this point in practice |
| practicePass | 1 = participant passed practice 0 = participant did not pass practice |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
Design |
||
| minPracticeAcc | The minimum proportion correct during a practice run that moves participant to the test | 0.75 |
| numberPracticeTrials | The number of practice trials per practice run needs to be divisible by 4 | 4 |
| maxPracticeRuns | The maximum number of practice runs | 3 |
| numberTestTrials | The number of test trials run needs to be divisible by 4 | 20 |
Timing Parameters |
||
| targetDelay | The delay (in ms) of the target relative to onset of flankers | 100 |
| cueDuration | The duration (in ms) of the cue 'middle' reminder | 1000 |
| homeBaseReminder | The delay (in ms) of the home base reminder if finger is not returned to home base | 2000 |
| iti | The intertrial interval (in ms) | 800 |
| errorFeedbackDuration | The duration (in ms) of error feedback during practice | 5000 |
| correctFeedbackDuration | The duration (in ms) of correct feedback during practice | 2000 |