Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 04, 2013
Last Modified: January 19, 2023 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements the Symbol Counter Task to study allocation of attentional resources within working memory.
The implemented procedure is based on:
Garavan, H., Ross, T.J., Li, S.J., & Stein, E.A. (2000). A parametric manipulation of central executive functioning. Cereb Cortex, 10, 585-92.
18 minutes
Participants are presented 18 sequences of small and big squares and have to keep a separate count for each of the two squaretypes. Afterwards, participants are asked to select the count for each squaretype out of 20 possible options and receive feedback.
6 number of sequential squares x 3 types of switchFrequencies (high, medium, low) = 18 trial sequences
• Number of Squares: 11, 12, 13, 14, 15, 16
• Switch Frequencies: number of times the sequence switches from one symbol to the other
high -> floor(number of squares /2); e.g. floor(15/2) = 7
medium -> floor (number of squares/4); e.g. e.g. floor(15/4) = 3
low -> 1
TRIAL SEQUENCE:
trial.start
trial.presentSquares (loops until all squares are presented)
-> surveyPage.symbolCount
-> trial.feedback
-> trial.rest
•observed trial sequence (default):
repeat for as many squares as need to be shown (trial.presentSquares)
• fixation cross for 100ms
• square for 1500ms
Then:
• select correct counts out of 20 possible options (0-20); maximum time to accomplish this is
12s (surveyPage.symbolCount)
• receive feedback in the form of correct counts for 1000ms (trial.feedback)
• rest for a predetermined amount of time before next trial starts (a clock presents number of seconds)
(trial.rest)
=> 18 trials divided into 2 parts by a longer rest
2 types of black squares: small vs big
presented in form of pictures that can be easily substituted by others
Instructions are not original to the task. They are provided by Millisecond
as htm/html pages and can be edited by changing the provided htm/html files.
To edit htm/html-files: open the respective documents in simple Text Editors such as TextEdit (Mac)
or Notepad (Windows).
File Name: symbolCountertask_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 |
| totalCorrect | Number of times participants was correct on both counts |
| pctTotalCorrect | Percentage of times participant was correct on both counts |
File Name: symbolCountertask_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 |
| squareNumber | The current length (number of squares presented) |
| switchIntensity | The currently selected switchIntensity (1 = low; 2 = medium; 3 = high) |
| switchFrequency | The calculated switch frequency (based on squareNumber and switchIntensity) |
| switchPositions | A string variable that stores all switchPositions in order from lowest to highest |
| symbolOrder | String variable that stores the order of the presented symbols (1 = small; 2 = big ) |
| countSymbol1 | Counts the number of symbol1 (small squares) cards that have been presented |
| countSymbol2, | Counts the number of symbol2 (big squares) cards that have been presented |
| dropdown.countSymbol1.response | The participant's count of symbol 1 (small squares) cards |
| dropdown.countSymbol2.response | The participant's count of symbol 2 (big squares) cards |
| correctCount1 | 1 = participant counted symbol1 cards correctly 0 = participant did not count symbol1 cards correctly |
| correctCount2 | 1 = participant counted symbol2 cards correctly 0 = participant did not count symbol2 cards correctly |
| correct | 1 = both of participant's count are correct 0 = otherwise |
| rt | Latency of response in ms (selecting the two counts) |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| symbol1Label | The label of symbol1 (here: SMALL Square) | |
| symbol2Label | The label of symbol2 (here: BIG Square) if you use different symbols, change the labels below | |
| pictureHeight | The height of the symbol picture Duration Parameters | 50% |
| fixationCrossPresentation | Fixation cross duration | 100ms |
| cardPresentationDuration | Duration of card presentation | 1500ms |
| responseDuration | Time participants have to select countnumbers | 12000ms |
| feedbackDuration | Time feedback (here: correct counts) is presented | 1000ms |
| restDurationRegular | Time of the resting trial between trial sequence | 15000ms |
| restDurationLong | Time of rest in between the first 9 trials and the second 9 trials | 120000ms |
| showCorrectCounts | Debug element if set to true: correctCounts are presented in red during the count selection trial false = counts are not presented (default). | |
| skipPractice | False = a practice sequence is run (default); true = no practice is given |