___________________________________________________________________________________________________________________ *SERIAL SUBTRACTION TASK* ___________________________________________________________________________________________________________________ Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC Date: 06-20-2016 last updated: 02-28-2022 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC Script Copyright © 02-28-2022 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements a Serial Subtraction Task akin to the Serial7/Serial3 task. The Serial Subtraction Task is a working memory performance task of the 'updating' category. The implemented procedure is based on: Kennedy, D.O. & · Andrew B. Scholey, A.B. (2000). Glucose administration, heart rate and cognitive performance: effects of increasing mental effort. Psychopharmacology (2000) 149:63–71. Note: in this script, the Serial Subtraction task uses written input instead of oral input ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Participants are given a randomly generated 3 digit number between 900-999 and are asked to subtract 7 (default) as often as they can within a 2 minute time frame (adjustable). Participants enter their solution by selecting digit buttons 0-9 with the mouse. Responses can be corrected before submit. Correct solutions are based on the last entered number (whether or not that response was correct). ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 2 minutes to complete (duration can be edited under section Editable Parameters) ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'serialsubtractiontask_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. currentNumber: contains the current start Number to be presented (parameter) targetDiff: contains the target difference between numbers (here: 3) correctSolution: stores the current correct solution Note: the current correct solution number is generated based on the last proposed solution. Thus if the last proposed solution was incorrect, the new correct solution is based on the incorrect proposed solution proposedSolution: stores the entered proposed solution for the current subtraction correct: the correctness of the response (1 = correct; 0 = incorrect) latency: the response latency (in ms); measured from onset of response dial countResponses: counts the number of given responses countErrors: counts the number of errors made (2) Summary data file: 'serialsubtractiontask_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) (parameter) targetDiff: contains the target difference between numbers (here: 7) RoundCount: counts the number of rounds run (default: 1 round with difference = 7) countResponses: counts the number of given responses countErrors: counts the number of errors made * separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section "DATA" and follow further instructions ___________________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ This Inquisit script provides a template for a Serial Subtraction Task. The target Difference can be set under Editable Parameters. By default, participants are asked to perform a Serial7 task. Participants are given a target number and are asked to start subtracting 7 from it in their heads. They enter their solution to each new subtraction via a response dial. The response is evaluated in regard to the previously entered solution (whether or not that was a correct solution). The task is over after 2 minutes (default) ___________________________________________________________________________________________________________________ STIMULI ___________________________________________________________________________________________________________________ randomly generated 3 digit start numbers (generated without replacement across blocks) between 900-999 ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ Instructions are not original to the task. They are provided by Millisecond Software as htm/html pages and simple page elements and can be edited either by changing the provided htm/html files or directly under Editable Instructions. 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: /TargetDiff: the target difference btw. numbers (here: 7) /taskDuration: task duration in ms (default: 120000ms = 2 min) /circleproportion: proportion of canvas height used for the circle radius of response buttons (default: 0.3)