Emotion Dot Probe Task with images for young children

Technical Manual

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

credit: Millisecond thanks Dr. Eva Kimonis for sharing the original images!

Created: April 10, 2026

Last Modified: April 10, 2026 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements an Emotion Dot Probe task with images for preschoolers, based on published studies by E. Kimonis and colleagues (see Kimonis et al, 2016) as well as provided script. Dot Probe Tasks are designed to measure (implicit) attentional bias— the tendency of our attention to be automatically drawn toward (or away from) certain types of stimuli, such as threatening or emotional information.

The Emotion Dot Probe with images task provides facilitation indices for each emotion tested that provide objective measurements of the impact of emotional information on response times (and response accuracy). By default, this script runs image pairs consisting of 'distress and neutral' and 'positive and neutral' pairings (in addition to the baseline/control pairings of 'neutral-neutral' pairings).

The current script is intended to be run with preschool aged children (ages 3-6).

References

Kimonis, E. R., Fanti, K. A., Anastassiou-Hadjicharalambous, X., Mertan, B., Goulter, N., & Katsimicha, E. (2016). Can Callous-Unemotional Traits be Reliably Measured in Preschoolers? Journal of Abnormal Child Psychology, 44(4), 625–638. https://doi.org/10.1007/s10802-015-0075-y

Kimonis, E. R., Frick, P. J., Fazekas, H., & Loney, B. R. (2006). Psychopathy, aggression, and the processing of emotional stimuli in non-referred girls and boys. Behavioral Sciences & the Law, 24(1), 21–37. https://doi.org/10.1002/bsl.668

Kimonis, E. R., Frick, P. J., Munoz, L. C., & Aucoin, K. J. (2007). Can a Laboratory Measure of Emotional Processing Enhance the Statistical Prediction of Aggression and Delinquency in Detained Adolescents with Callous-unemotional Traits? Journal of Abnormal Child Psychology, 35(5), 773–785. https://doi.org/10.1007/s10802-007-9136-1

Kimonis, E. R., Frick, P. J., Munoz, L. C., & Aucoin, K. J. (2008). Callous-unemotional traits and the emotional processing of distress cues in detained boys: Testing the moderating role of aggression, exposure to community violence, and histories of abuse. Development and Psychopathology, 20(2), 569–589. https://doi.org/10.1017/S095457940800028X

Kimonis, E. R., Frick, P. J., Cauffman, E., Goldweber, A., & Skeem, J. (2012). Primary and secondary variants of juvenile psychopathy differ in emotional processing. Development and Psychopathology, 24(3), 1091–1103. https://doi.org/10.1017/S0954579412000557

Duration

4 minutes

Description

Each dot probe trial starts with a fixation stimulus (here: a mouse 'Jerry' image) in the center of the screen, followed by a brief presentation of two (paired) images. One image is presented above the fixation cross and the other is presented below it. Once the image pair is erased, a probe stimulus (here: a picture of a slice of cheese) appears in the position of one of the images and participants are asked to press the T(op) or B(ottom) keys as fast as possible to indicate the position of the dot (aka 'to feed Jerry').

The image pairs come from different categories: 1. neutral-neutral pairings 2. distress-neutral pairings

Procedure

Design
2 stim pair conditions (neutral-neutral; distress-neutral) x 2 target positions (top vs. bottom) x 2 congruence (congruent vs. incongruent)
x 1 repetitions per block x 3 blocks = 24 trials total

(1) Practice
• 1 block of 8 trials ( this script provides 8 unique image pairings for the practice session)
• image pairs are selected randomly

(2) Test
• 3 blocks of 8 trials each; 24 trials total
• each block runs:
- 4 neutral-neutral pairings; 2 present 'target' on top (two of those are followed by probes); image pairs randomly (without replacement) selected from respective image pool
- 4 distress-neutral pairings; 2 present 'target' on top (two of those are followed by probes); image pairs randomly (without replacement) selected from respective image pool
• order of stimuli pairs is randomly determined (a random image pair is selected without replacement from the pool of available test image pairs)

Trial Sequence (Durations Editable)
Fixation (500ms) -> Image Pair (500ms) -> Probe (max. responsetime: 5000ms) -> iti (2000ms)

Stimuli

This script uses the stimuli (pairs) provided by Dr. Eva Kimonis .
• 8 practice image pairs
• 12 neutral-neutral test image pairs
• 12 neutral-emotion test image pairs

The images are listed under section Editable Stimuli

Instructions

The instructions are based on the instructions used by Dr. Kimonis and colleagues.
They are listed - and can be edited- in script 'edp_images_ps_instructions_inc.iqjs'.

Scoring

Facilitationindexdistressacc,Facilitationindexpositiveacc
calculated as: 0.5 * ((propCorrNeutralUp - propCorrectConDistressUp) + (propCorrectNeutralDown - propCorrectConDistressDown))

propCorrectNeutralUp: the proportion correct responses in neutral-neutral trials where the probe appeared above the fixation cross
propCorrectNeutralDown: the proportion correct responses in neutral-neutral trials where the probe appeared below the fixation cross

propCorrectConDistressUp: the proportion correct responses in CONGRUENT distress-neutral trials where the distress target/probe appeared above the fixation cross
propCorrectConDistressDown: the proportion correct responses in CONGRUENT distress-neutral trials where the distress target/probe appeared below the fixation cross

=> This formula controls for potential location effects (participant’s tendency to attend to either the top or bottom location of the screen)
by summing latencies for top and bottom picture locations and taking their average.
=> The higher the facilitationIndex, the more the emotional images 'grabbed' a person's attention

Summary Data

File Name: edp_images_ps_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
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
Trialcounts
con1 Number of congruent neutral-neutral trials (probe sits in dedicated 'target' position), congruence not meaningfule for neutral-neutral trials
incon1 Number of incongruent neutral-neutral trials (probe sits in dedicated 'comp' position), congruence not meaningfule for neutral-neutral trials
validCorrRTCon1 Number of correct congruent neutral-neutral trials with RT >= parameters.minRT
validCorrRTIncon1 Number of correct incongruent neutral-neutral trials with RT >= parameters.minRT
con2 Number of congruent distress-neutral trials (probe sits in 'distress' position)
incon2 Number of incongruent distress-neutral trials (probe sits in 'neutral' position)
validCorrRTCon2 Number of correct congruent distress-neutral trials with RT >= parameters.minRT
validCorrRTIncon2 Number of correct incongruent distress-neutral trials with RT >= parameters.minRT
Accuracy (Acc)
propCorrCon1 Proportion Correct Congruent neutral-neutral trials (probe sits in dedicated 'target' position), congruence not meaningfule for neutral-neutral trials
propCorrIncon1 Proportion Correct Incongruent neutral-neutral trials (probe sits in dedicated 'comp' position), congruence not meaningfule for neutral-neutral trials
propCorrCon2 Proportion Correct Congruent distress-neutral trials (probe sits in 'distress' position)
propCorrIncon2 Proportion Correct Incongruent distress-neutral trials (probe sits in 'neutral' position)
propCorrUp1 Proportion Correct neutral-neutral trials with probe in Top position
propCorrDown1 Proportion Correct neutral-neutral trials with probe in Bottom position
propCorrConUp2 Proportion Correct CONGRUENT distress-neutral trials with distress & probe in Top position
propCorrConDown2 Proportion Correct CONGRUENT distress-neutral trials with distress & probe in Bottom position
facilitationIndexDistressAcc ACC Faciliation Score for Distress images (that are followed by a probe) compared to neutral images (followed by a probe)
=> the higher the score, the more the emotional content of the images 'captured' attention and faciliated correct responding
=> negative scores imply that the emotional images were avoided compared to neutral counterparts
Response Time (Rt): Only Correct Responses With Latencies >= Parameters.Minrt Considered
meanCorrRTCon1 Mean correct response time in Congruent neutral-neutral trials (probe sits in dedicated 'target' position), not meaningfule for neutral-neutral trials
meanCorrRTIncon1 Mean correct response time in Incongruent neutral-neutral trials (probe sits in dedicated 'comp' position), not meaningfule for neutral-neutral trials
meanCorrRTCon2 Mean correct response time in Congruent distress-neutral trials (probe sits in 'distress' position)
meanCorrRTIncon2 Mean correct response time in Incongruent distress-neutral trials (probe sits in 'neutral' position)
meanCorrRTUp1 Mean correct response time in neutral-neutral trials with probe in Top position
meanCorrRTDown1 Mean correct response time in neutral-neutral trials with probe in Bottom position
meanCorrRTConUp2 Mean correct response time in CONGRUENT distress-neutral trials with distress & probe in Top position
meanCorrRTConDown2 Mean correct response time in CONGRUENT distress-neutral trials with distress & probe in Bottom position
facilitationIndexDistressRT RT Faciliation Score for Distress images (that are followed by a probe) compared to neutral images (followed by a probe)
=> the higher the score, the more the emotional content of the images 'captured' attention and faciliated faster responding
=> negative scores imply that the emotional images were avoided compared to neutral counterparts and thus response times were slower

Raw Data

File Name: edp_images_ps_raw*.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
blockcode The name the current block (built-in Inquisit variable)
blocknum The number of the current block (built-in Inquisit variable)
trialcode The name of the currently recorded trial (built-in Inquisit variable)
trialnum The number of the currently recorded trial (built-in Inquisit variable)
trialnum is a built-in Inquisit variable; it counts all trials run
even those that do not store data to the data file.
phase "Practice" vs. "Test"
blockCounter Tracks the number of test blocks run
trialCounterPerBlock Tracks the number of trials run per block (resets for each block)
condition 0 = practice
1 = neutral-neutral (control condition)
2 = distress-neutral
targetLocation The location of the assigned target ( in condition 2, the targets are the emotion images)
0 = top
1 = bottom
probeLocation 0 = top
1 = bottom
congruence 0 = incongruent (probe follows comp - neutral image)
1 = congruent (probe follows target - distress, positive image)
index Image itemnumber
targetImage Stores the currently presented target image
compImage Stores the currently presented comp image
corrResp Stores the currently correct response key (T=top, B=bottom)
response The response of participant (scancode of response button)
responseText The label of the response button
correct Correctness of response (1 = correct, 0 = error)
latency Response latency (in ms); measured from: onset of probe
Debug Variables
picture.target.y Stores the vertical coordinate of the current target image
picture.comp.y Stores the vertical coordinate of the current comp image
picture.probe.y Stores the vertical coordinate of the current probe stim (for congruent trials, this should be the same as the target image)

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
Design
numberTestBlocks Number of test blocks to run
this script provides 12 distress-neutral and 12 neutral-neutral image pairs for the 3 blocks x 8 trialsPerBlock = 24 test trials
If this number is set to a higher blockcount, image pairs will be repeated.
3
Sizing Parameters
fixationHeightPct Relative height (to canvas height) of fixation cross8%
imageHeightPct Relative height (to canvas height) of each image40%
probeHeightPct Relative height (to canvas height) of the probe stim8%
topY Vertical percentage coordinate of the top image ( top=0% to bottom=100%)25%
bottomY Vertical percentage coordinate of the bottom image ( top=0% to bottom=100%)75%
Timing Parameters
fixationDurationMS Duration (in ms) of solitary fixation cross at the beginnin of each trial500
stimDurationMS Duration (in ms) of image pair750
responseTimeoutMS Max. time (in ms) that participants have to respond to the probe stimulus5000
itiMS Intertrial interval (in ms)2000
minRT Minimum response latency (in ms) that is considered 'valid'0
Responsekeys
topResponseKey The dedicated key to indicate TOP probes ( T is located ABOVE B on QWERTY keyboards)"T"
bottomResponseKey The dedicated key to indicate BOTTOM probes ( B is located BELOW T on QWERTY keyboards)"B"