Reaction Time Concealed Information Test - RT-CIT

Technical Manual

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

Created: January 24, 2021

Last Modified: January 11, 2025 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements a 'Reaction Time Concealed Information Test' (RT-CIT), a procedure to detect information a person tries to conceal (Suchotzki et al, 2021).

The RT-CIT compares 'no' reaction time responses to probe and control items. The RT-CIT effect describes that people who deceptively deny recognizing information (the probes, e.g. crime relevant information) respond slower to the probe items than to control items (crime irrelevant information), particularly if a response timeout is built into the task which seems to reduce faking abilities (Suchotzki et al, 2021).

References

Suchotzki, K., Verschuere, B., & Gamer, M. (2021) How Vulnerable is the Reaction Time Concealed Information Test to Faking?, Journal of Applied Research in Memory and Cognition, https://doi.org/10.1016/j.jarmac.2020.10.003.

Duration

8 minutes

Description

The task involves responding to target, probe, and control items as soon as possible. The target items are the items to which participant should respond "Yes, I know them". The probe and control items are words to which participant should respond "No, I don't know them".

The 5 target ('Yes') items are learned at the beginning of the test. Probe items are items that are relevant to the task (e.g. crime-relevant information). Control items are items that task irrelevant.

The order of the items during the reaction time portion of the test are presented in random order.

Procedure

(1) Learning Phase: (see section Editable Parameters for 'Learning Phase' parameter settings)
By default, at least 3 learning rounds are run. If participants have recalled all five items
correctly after the last round, they move on to the test phase. Otherwise, another learning
round is added (up to 10, see section Editable Parameters).

- Learning screen: all 5 items are presented on screen for 30s
- Recall screen: 5 textboxes to enter the five items (in any order)

The computer compares the recalled items to the target items and counts the
number of correctly recalled items.
the algorithm implemented converts all items to lower case letter and removes empty spaces
commas and periods. However, spelling errors will still be identified as 'errors'.

(2) Test Phase:
- 5 target items repeated 6 times (30 trials)
- 5 probe items repeated 6 times (30 trials)
- 20 control items repeated 6 times (120 trials)
=> total of 180 trials, order is randomized (after 90 trials, a break trial is presented)

Trial Sequence:

word (Max: 800ms or until response)* -> variable iti (randomly selected from 500ms-1000ms in 100ms increments)
• if no response was made within 800ms: a 'too slow' message was presented for 1000ms before the iti.

Stimuli

provided by Millisecond as template stimuli only - can be edited under section Editable Stimuli

Instructions

provided by Millisecond - can be edited under section Editable Instructions

Summary Data

File Name: reactiontimeconcealedinformationtest_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
learningBlockCounter Tracks the number of learning rounds run
countCorrectRecall The number of correctly recalled items after the last learning round
learningPass 1 = the learning criterium was reached; 0 = otherwise
Note: No Response Time 'Cleaning' Was Done For The Following Summary Statistics
propCorrectTargets Proportion correctly categorized targets (as YES)
nrTargets The number of No responses to target items within the allotted response timeout
meanHitRTTargets Mean response time (in ms) of correctly categorizing targets
propCorrectProbes Proportion correctly categorized probes (as NO)
nrProbes The number of No responses to probe items within the allotted response timeout
meanCRRTProbes Mean response time (in ms) of correctly categorizing probes
propCorrectControls Proportion correctly categorized controls (as NO)
nrControls The number of No responses to control items within the allotted response timeout
meanCRRTControls Mean response time (in ms) of correctly categorizing controls
sdCRRTControls Standard deviation of response times of correctly categorizing controls (in ms)
rtdiff The response time difference of ('mean response time (in ms) of correctly categorizing probes' - 'mean response time (in ms) of correctly categorizing controls')
rtCITEffect 1: participant was on average slower to categorize probe items compared to control items
0: everything else

Raw Data

File Name: reactiontimeconcealedinformationtest_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.
trialCounter Tracks the number of trials run during the test
word Stores the currently presented word
itemNumber Stores the currently presented itemnumber of the word
response The participant's response (scancode of response buttons)
30 = A
38 = L
57 = space
responseText The label of the pressed response key ( it appears empty for space)
correct Accuracy of response: 1 = correct response; 0 = otherwise
latency The response latency (in ms); measured from: onset of word
Learning Phase
recall1 The 1. recalled item (in 'cleaned' format)
recall2 The 2. recalled item (in 'cleaned' format)
recall3 The 3. recalled item (in 'cleaned' format)
recall4 The 4. recalled item (in 'cleaned' format)
recall5 The 5. recalled item (in 'cleaned' format)
targetStorage Stores all the target words (in 'cleaned' format)
countCorrectRecall Tracks the number of correctly recalled items

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
Design
minLearningBlocks The minimum number of times block.targetLearning has to run 3
maxLearningBlocks The maximum number of times block.targetLearning has to run 10
learningCriteriumAcc The percent correct recall of the 5 target words after the last learning block100%
prematureAbortLearningFail True = the script prematurely ends if the learning criterium has not been reached after all learning blocks have run
false = the script moves from learning to test even if the learning criterium has not been reached
false
Sizing Parameters
stimSize The proportional height (to canvas height) of the presented stims5%
Timing Parameters
targetLearningDuration The duration (in ms) that all five target words are presented during the learning phase30000
getReadyDuration The duration (in ms) of the get-ready sign before the start of the test5000
maxStimDuration The maximum duration (in ms) that the words are on screen
this is also the response timeout (default: 800ms)
800
feedbackDuration The duration (in ms) of the 'too slow' feedback message 1000
Response Key Assignment
leftKey The assigned left key (on a QWERY keyboard)"A"
rightKey The assigned right key (on a QWERY keyboard)"L"
yesKey The assignment of left/right key to be the 'yes' keyparameters.leftKey
noKey The assignment of left/right key to be the 'no' keyparameters.rightKey