Line Counting Task

Technical Manual

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

This task has been generously made available to the Millisecond Script Library by Dr. James Bjork.

Created: January 28, 2018

Last Modified: January 03, 2023 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements a line counting task, an attentional bias task with target images.

References

Passamonti, L. et al (2017). Atomoxetine effects on attentional bias to drug-related cues in targetCategory dependent individuals. Psychopharmacology (2017) 234:2289–2297.

Duration

8 minutes

Description

Participants view pictures of targetCategory (here: cocaine) related and neutral images. Each image has 2-5 blue lines drawn on it. Participants are asked to indicate the number of lines by button press.

Procedure

(1) Cravings Rating

(2) practice (with feedback): 30 trials with neutral images
- images are selected randomly from the 30 provided practice images
practice session can be repeated as long as the number of practice sessions is
below parameters.maxPracticeSessions (default: 2, editable parameters)

(3) Test (no feedback): 9 runs of 16 trials: 8 targetCategory and 8 neutral images
(image conditions are presented in blocked format; the starting condition - targetCategory vs. neutral- is selected
based on groupnumber:
groupnumber 1: target category -> neutral (C->N)
groupnumber 2: neutral -> target category (N->C)

- images for each condition are selected randomly (without replacement) from the provided pool
of 72 targetCategory images and 72 neutral images

Response Keys:
z -> 2 stripes
x -> 3 stripes
n -> 4 stripes
m -> 5 stripes


the iti is randomly selected from a normal distribution around parameters.itiMean (default: 1750ms) with SD = parameters.itiStd
(default: 500ms) and with max itis = parameters.itiMax (default: 3100ms) and minimum itis = parameters.itiMin (default: 1100ms)

Stimuli

provided by Dr. James Bjork

Instructions

see section Editable Instructions

Summary Data

File Name: linecountingtask_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
targetCategoryCravingRating The selected rating for the craving of the target substance (1-9)
countPracticeRuns Counts the number of practice sessions run
stimOrder "C->N" vs. "N->C" (the start of the testing blocks)
interferenceMeanRTDerived The interference score in ms: calculate as 'meanRTTargetCategory - meanRTNeutral' (Main DV)
=> positive: it took partipants on average longer to reply to target Category
images than to neutral images (attentional bias)
interferenceMedianRTDerived The interference score in ms: calculate as 'medianRTTargetCategory - medianRTNeutral'
=> positive: it took partipants on average longer to reply to
target Category images than to neutral images (attentional bias)
meanRTTargetCategory Mean response time (in ms) of correct responses to targetCategory related images
medianRTTargetCategory Median response time (in ms) of correct responses to targetCategory related images
meanRTNeutral Mean response time (in ms) of correct responses to neutral images
medianRTNeutral Median response time (in ms) of correct responses to neutral images
propCorrectTargetCategory Proportion correct responses to targetCategory related images
propCorrectNeutral Proportion correct responses to neutral images
propTimeoutTargetCategory Proportion timed-out responses (=no responses) to targetCategory related images
propTimeoutNeutral Proportion timed-out responses (=no responses) to Neutral related images

Raw Data

File Name: linecountingtask_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
stimOrder "C->N" vs. "N->C" (the image sequence per run)
C->N: each run runs 8 targetCategory images and then 8 neutral images
N->C: each run runs 8 neutral images and then 8 targetCategory images
countPracticeRuns Counts the number of practice sessions run
countTestRuns Counts the number of test runs (there should be 9 runs with 16 stims each, 8 targetCategory and 8 neutral)
blockCode Name of the current block
blockNum Number of the current block
trialCode Name of the current trial
trialNum Number of the current trial
stimulusType NEUTRAL vs. targetCategory
stimulusItem Stores the image file presented
numberOfStripesInStimulus Stores the number of stripes
correctResponse Z, X, N, M
response The scancode of the key response (44 = Z, 45 = X, 49 = N, 50 = M)
responseText For test trials: the character key that was pressed -> Z, X, N, M
correct 1 = correct, 0 = error/no response
responseOutcome CORRECT, INCORRECT, NONE
trialOutcome CORRECT, WRONG, NO RESPONSE
responseTime Response time in ms; measured from onset of image up until response button is hit
if no response => values.responseTime = ""
iti The jittered ITI, iti is randomly selected from a normal distribution
around parameters.itiMean with SD = parameters.itiStd (with minimum iti = parameters.itiMin
and maximum iti = parameters.itiMax)
targetCategoryCravingRating The selected rating for the craving of the target substance (1-9)

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
picSize Proportional (to canvas height) sizing of the images 80%
maxPracticeSessions Maximum number of practice sessions that can be run 2
waitDuration The duration (in ms) of the wait-trial 2000ms
picDuration The duration (in ms) of the images
Intertrial Interval (in ms) Sampling
900ms
iTiMean The mean of the normal distribution itis are sampled from 1750ms
itiStd The standard deviation of the normal distribution itis are sampled from 500ms
itiMax The maximum iti 3100ms
itiMin The minimum iti 1100ms