___________________________________________________________________________________________________________________ *SYMBOL COUNTER TASK* ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 10-04-2013 last updated: 10-19-2023 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 10-19-2023 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ 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. ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ 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. ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 18 minutes to complete ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'symbolcountertask_raw*.iqdat' (a separate file for each participant) build: The specific Inquisit version used (the 'build') that was run computer.platform: the platform the script was run on (win/mac/ios/android) date, time: date and time script was run subject, group: with the current subject/groupnumber session: with the current session id blockcode, blocknum: the name and number of the current block (built-in Inquisit variable) trialcode, trialnum: the name and number of the currently recorded trial (built-in Inquisit variable) Note: trialnum is a built-in Inquisit variable; it counts all trials run; even those that do not store data to the data file such as feedback trials. Thus, trialnum may not reflect the number of main trials run per block. 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) (2) Summary data file: 'symbolcountertask_summary*.iqdat' (a separate file for each participant) inquisit.version: Inquisit version run computer.platform: the platform the script was run on (win/mac/ios/android) startDate: date script was run startTime: time script was started subjectid: assigned subject id number groupid: assigned group id number sessionid: assigned session id number elapsedTime: time it took to run script (in ms); measured from onset to offset of script completed: 0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run) totalcorrect: number of times participants was correct on both counts perc_totalcorrect: percentage of times participant was correct on both counts ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ 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 <selects number of squares/switchfrequency> -> <utility trials that assemble list.switchpositions> -> 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 ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ 2 types of black squares: small vs big presented in form of pictures that can be easily substituted by others ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ Instructions are not original to the task. They are provided by Millisecond Software 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). ___________________________________________________________________________________________________________________ EDITABLE CODE ___________________________________________________________________________________________________________________ check below for (relatively) easily editable parameters, stimuli, instructions etc. Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment. The parameters you can change are: /symbol1_label: the label of symbol1 (here: SMALL Square) /symbol2_label: the label of symbol2 (here: BIG Square) Note: if you use different symbols, change the labels below /pictureheight: the height of the symbol picture (default: 50%) Duration Parameters: /fixationcrosspresentation: fixation cross duration (default: 100ms) /cardpresentationduration: duration of card presentation (default: 1500ms) /responseduration: time participants have to select countnumbers (default: 12000ms) /feedbackduration: time feedback (here: correct counts) is presented (default: 1000ms) /restduration_regular: time of the resting trial (default: 15000ms) between trial sequence /restduration_long: time of rest in between the first 9 trials and the second 9 trials (default: 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