Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 02, 2018
Last Modified: January 12, 2025 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements the Dots Task. The Dots Task is a spatial incompability task with arbitrary shape stimuli similar to the Simon Task. The Dots Task was designed to target working memory and inhibition.
Dots Task Reference:
M.C. Davidson, D. Amso, L.C. Anderson, A. Diamond (2006). Development of cognitive control and executive functions from 4 to 13 years: Evidence from manipulations of memory, inhibition, and task switching. Neuropsychologia 44, 2037–2078
Simon Task Reference:
Simon, J.R. and Wolf, J.D. (1963). Choice reaction times as a function of angular stimulus-response correspondence and age. Ergonomics, 6, 99-105.
Bialystok, E., Craik, F. I. M., Klein, R., & Viswanathan, M. (2004). Bilingualism, Aging, and Cognitive Control: Evidence From the Simon Task. Psychology and Aging, 19(2), 290-303.
2 minutes
Participants are presented trials with either a red circle or a blue circle that appear to the left or right of a fixation cross. If participants see a red circle, they are asked to press the corresponding left or right response button (=congruent trials). For example, if the red circle is left to the fixation cross, participants are asked to press the left response button. If participants see a blue circle, they are asked to press the opposite response button (=incongruent trials). For example, if the blue circle is left to the fixation cross, participants are asked to press the right response button.
1. Practice Block(s): a maximum of 3 (default, can be set under section Editable Parameters) practice blocks of
8 trials. If participants reach a performance of 75% correct (default, can be set under section Editable Parameters)
during any of the blocks, the test block is started - otherwise the script is aborted after 3 unsuccessful
practice blocks. During practice, participants receive positive feedback for 500ms if they
press the correct response button. For incorrect responses as well as noresponses, participants will get a
reminder of the rules and have to retry the trial (at this point, only correct responses are accepted to
move to the next trial).
2. Test: 10 'red circle' trials (5 red circles left, 5 red circles right), 10 'blue circle' trials
(5 blue circle left, 5 blue circle right)
=> random order with constraint that max. 3 of the same trials can be run consecutively
=> number of switch trials will vary (minimum number of switch trials = 6 for 20 trials)
switch trial: switch from congruent to incongruent trial and vice versa
number of trials per block can be set under section Editable Parameters
Trial Sequence:
stimulus (circle)-> max. 1750ms (editable) -> iti: 1000ms (editable)
(timings can easily be changed under section Editable Parameters)
provided by Millisecond - can be edited under section Editable Stimuli
provided by Millisecond - can be edited can be edited
in script "dotstask_touchscreen_instructions_inc.iqjs"
File Name: dotstask_touchscreen_summary*.iqdat
| Name | Description |
|---|---|
| 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 |
Practice Performance |
|
| countPractice | Counts the number of practice blocks run |
| practiceAcc | The highest proportion correct in one of the practice blocks (if not run, propCorrect = 0) |
| practicePass | 1 = participant successfully passed the practice session 0 = otherwise |
Test Performance |
|
| propCorrect | Proportion correct across all test trials |
| meanRT | Mean latency of correct responses across all test trials |
| propCorrectSwitch | Proportion correct across switch trials |
| meanRTSwitch | Mean latency of correct responses across switch test trials witch trial: switch from congruent to incongruent trial and vice versa |
| propCorrectNonSwitch | Proportion correct across nonswitch trials |
| meanRTNonSwitch | Mean latency of correct responses across nonswitch test trials |
| propCorrectCongruent | Proportion correct across congruent test trials |
| meanRTCongruent | Mean latency of correct responses across congruent test trials |
| propCorrectIncongruent | Proportion correct across incongruent test trials |
| meanRTIncongruent | Mean latency of correct responses across incongruent test trials |
| simonEffec | Ms difference in "[mean corrRT Incongruent] - [mean corrRT Congruent]" positive value: participants responded faster when stimulus location and response button location were congruent ("stimulus-response compatibility") => Simon Effect [negative value: participants responded faster when stimulus location and response button location were incongruent] |
File Name: dotstask_touchscreen_raw*.iqdat
| Name | Description |
|---|---|
| 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 |
| practice | 1 = practice block 0 = test |
| position | 1 = stimulus is positioned on the left 2 = stimulus is positioned on the right |
| congruence | 1 = congruent trial 2 = incongruent trial |
| prevCongruence | The congruence of the previous trial (important for mixed condition only) |
| switch | 1 = switch trial (trial type changed from congruent to incongruent or vice versa) 2 = nonswitch trial (trial type stayed the same) |
| countSwitch | Counts the number of switch trials per block |
| stimulusItem | The presented stimuli in order of trial presentation |
| response | The participant's response leftResponseButton rightResponseButton |
| correct | Accuracy of response 1 = correct response 0 = otherwise |
| latency | The response latency (in ms); measured from: onset of stim |
| list.accPractice.mean | The proportion correct during the current practice block |
| countPractice | Counts the number of practice blocks run |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| minPracticeAcc | The minimum practice performance (proportion correct) to let participants move from a practice block to a test block (default: 0.75) | |
| maxPracticeRepeats | Number of times a practice blocks can be repeated before the script is aborted | 3 |
| numberPracticeTrials | The number of practice trials per practice block | 8 |
| numberTestTrials | The number of test trials per test block the number of trials should be divisible by 4 | 20 |
| stimDuration | The duration (in ms) of the stimulus presentation (= response timeout) | 1750 |
| iti | The intertrial interval (in ms) | 1000 |
| picSize | The proportional sizing (proportional to canvas height) of the pictures | 10% |
| fixationSize | The proportional sizing (proportional to canvas height) of the fixation cross | 15% |
| leftX | The left x-coordinate in canvas percentage | 30% |
| rightX | The right x-coordinate in canvas percentage left edge of canvas = 0%, right edge of canvas = 100% (canvas = portion of the screen dedicated for the script) | 70% |