Mental Arithmetic Task

Technical Manual

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond

Created: January 04, 2018

Last Modified: January 11, 2024 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements a Mental Arithmetic Task based on:

KAHNEMAN D., TURSKY, B., SHAPIRO, D. & CRIDER, A. (1969). PUPILLARY, HEART RATE, AND SKIN RESISTANCE CHANGES DURING A MENTAL TASK. Journal of Experimental Psychology, 79, No. 1, 164-167.

Duration

15 minutes

Description

Participants are presented series of 4 digits and are asked to mentally add* a number (0, 1, 2 or 3) to each digit. The new sequence is reported by entering the new digits in provided textboxes.

The script can be altered to run either addition, subtraction or multiplication sequences as well as test any levels from 0-9.

Procedure

(1) Practice:
• by default the practice session runs 8 trials (2 trials per levels 0, 1, 2, 3); levels randomly selected
(change the number of trials under section Editable Parameters; change the levels tested under section Editable Lists)

(2) Test:
- the test runs random selections of levels 0-3 ( levels can be edited under section Editable Lists)
- once a level reaches criteria (5 correct solutions -> see section Editable Parameters for possible edits),
it is not further selected
- the test ends once all levels reach criteria OR if the maximum allowed test time expires
(default: 1h; see section Editable Parameters for possible edits)

Sequence Selection:
- each digit sequences randomly selects 4 different digits
- the script ensures as much as possible (without noticeably slowing down the selection process)
that each presented digit sequence during the practice and test session is unique.
For a random selection of 4 digits from 10 possible digits (no repeats), there are 5040 possible unique sequences.
The script resets the list of unique sequences after 1000 sequences have been provided (thus repeats are possible after each
block of 1000 trials, but it's unlikely that 1000 sequences are going to be run)

Default Trial Sequence (can be edited under section Editable Parameters):
Get Ready (1000ms) -> blank (4000ms) ->
task instructions (2000ms) -> blank (3000ms) ->
1. digit (1000ms) -> blank (0ms) ->
2. digit (1000ms) -> blank (0ms) ->
3. digit (1000ms) -> blank (0ms) ->
4. digit (1000ms) -> blank (1000ms) ->
presentation of input-textboxes (max. 60000ms) ->
feedback (optional for test):
positive feedback: 200ms
error feedback: until participants decides to continue ->
iti (blank screen for 1000ms)

Stimuli

digits: change size under section Editable Parameters

Instructions

provided by Millisecond - can be edited under section Editable Instructions

Summary Data

File Name: mentalArithmetictask_summary*.iqdat

Data Fields

NameDescription
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
arithmeticProcedure The math task to perform: choose from "add", "subtract", "multiply" (the default one is "add")
levels Stores all the levels run (default setup: 0123)
maxCorrectSolutions The exit criteria: number of problems participants have to get correct at each tested levels
to exit the script (default: 5)
passedTest 0 = test terminated because max. allowed time was up
1 = otherwise (reached criteria for all levels tested)
trialCount Number of test trials run
count0 Counts the number of level 0 test trials
countCorrect0 Counts the number of correct level 0 test trials
count1 Counts the number of level 1 test trials
countCorrect1 Counts the number of correct level 1 test trials
count2 Counts the number of level 2 test trials
countCorrect2 Counts the number of correct level 2 test trials
count3 Counts the number of level 3 test trials
countCorrect3 Counts the number of correct level 3 test trials
The following variables will be empty for the default script set-up and could be removed from the data file
count4 Counts the number of level 4 test trials (default settings: "not run")
countCorrect4 Counts the number of correct level 4 test trials
count5 Counts the number of level 5 test trials
countCorrect5 Counts the number of correct level 5 test trials
count6 Counts the number of level 6 test trials
countCorrect6 Counts the number of correct level 6 test trials
count7 Counts the number of level 7 test trials
countCorrect7 Counts the number of correct level 7 test trials
count8 Counts the number of level 8 test trials
countCorrect8 Counts the number of correct level 8 test trials
count9 Counts the number of level 9 test trials
countCorrect9 Counts the number of correct level 9 test trials

Raw Data

File Name: mentalArithmetictask_raw*.iqdat

Data Fields

NameDescription
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, group, With the current subject/groupnumber
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
arithmeticProcedure The math task to perform: choose from "add", "subtract", "multiply" (the default one is "add")
trialCount Counts the trials in the practice/test block (resets after practice)
level The current level tested (default: 0, 1, 2, 3)
digitSequence The digits in the order presented (e.g. "3456")
corrSolution Contains the correct solution for the current digit sequence
currentResponse Contains the entered digits (in sequence)
textbox.digit1Response.response-
textbox.digit4Response.response Entered digits by textbox
acc 1 = the entered solution is correct (correct digits and order)
0 = otherwise
countCorrDigits Counts the number of correctly entered digits per trial
rt Stores the latency (in ms); measured from onset of textboxes to pressing the submit-button
count0 Counts the number of level 0 test trials
countCorrect0 Counts the number of correct level 0 test trials
count1 Counts the number of level 1 test trials
countCorrect1 Counts the number of correct level 1 test trials
count2 Counts the number of level 2 test trials
countCorrect2 Counts the number of correct level 2 test trials
count3 Counts the number of level 3 test trials
countCorrect3 Counts the number of correct level 3 test trials
The following variables will be empty for the default script set-up and could be removed from the data file
count4 Counts the number of level 4 test trials (default settings: "not run")
countCorrect4 Counts the number of correct level 4 test trials
count5 Counts the number of level 5 test trials
countCorrect5 Counts the number of correct level 5 test trials
count6 Counts the number of level 6 test trials
countCorrect6 Counts the number of correct level 6 test trials
count7 Counts the number of level 7 test trials
countCorrect7 Counts the number of correct level 7 test trials
count8 Counts the number of level 8 test trials
countCorrect8 Counts the number of correct level 8 test trials
count9 Counts the number of level 9 test trials
countCorrect9 Counts the number of correct level 9 test trials

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
maxCorrectSolutions The exit criteria: number of problems participants have to get correct at each level tested
to exit the script (default: 5)
maxTestTime The max duration (in ms) the test is running if exit-criteria is not met 3600000ms = 1h
testFeedback True (1) = performance feedback is provided during the test after each trial (default)
false (0) = performance feedback is not provided during the test
arithmeticProcedure The math task to perform: choose from "add", "subtract", "multiply" (the default one is "add")
digitSize The proportional sizing (to canvas height) of the presented digits 8%
readyDuration The duration (in ms) of the the 'get Ready' trial 1000ms
delayTaskInstructions The delay (in ms) of the task instructions (measured from onset of trial) 5000ms
taskInstructionDuration The duration (in ms) of the task instructions 2000ms
digit1Delay The delay (in ms) of the first digit (measured from onset of trial) 10000ms
digitDuration The duration (in ms) of the digit presentation 1000ms
digit2Delay The delay (in ms) of the second digit (measured from onset of trial) 11000ms
digit3Delay The delay (in ms) of the third digit (measured from onset of trial) 12000ms
digit4Delay The delay (in ms) of the fourth digit (measured from onset of trial) 13000ms
responseTimeout The response timeout (in ms) 60000ms
recallDelay The delay (in ms) of the recall textbox (measured from onset of 'get Ready')
script checks delay settings and aborts if conflicting
15000ms
feedbackDuration Duration (in ms) of positive feedback
errorfeedback is provided until participant is ready to move on
500
iti The intertrial interval in ms 1000