Reaction Time Concealed Information Test (RT-CIT)

Background

The Reaction Time Concealed Information Test (RT-CIT) is a computerized response-time test to uncover whether a person tries to hide crucial knowledge such as crime-relevant details. The use of response times to reveal "guilty knowledge" was demonstrated by K. J. Seymour and colleagues in their 2000 study investigating response time measures as possible alternatives to polygraph lie detectors.

In their study, they created mock crimes that their participants committed (and yes, a bit of deception was involved here). Several crucial details of these mock crimes such as "blue coat" were chosen as 'probe' items for a later response time task. After committing the mock crime and an additional number of distractor tasks, participants engaged in a simple categorization task (the main response time task). The categorization task was simple: press one key if the presented word is a 'target' and another if it's not. The words that were chosen for the categorization task consisted of the 'probe' items from the earlier mock crime (e.g. "blue coat") and related items (e.g. "green hat" or "brown shoes"). In a separate learning session, that took place before the actual categorization task, participants had already learned a subset of the similar words (e.g. "green hat") as the 'targets'.

Event Sequence: Crime ('blue coat') -> Target learning ('green hat') -> Categorization Task: "Is this a target?": blue coat (no), green hat (yes), brown shoes (no)

They found that participants were slower to correctly categorize crime-related probe items ("blue coat") as non-targets compared to the control items ("brown shoes") supporting that prior knowledge of information influences response times. The reason for this response time delay is probably a combination of an orienting response towards the 'guilty' knowledge that causes participants to pay extra attention to these items and the paradoxical effect of a primed memory (because they know these items) that prepares the brain to make the (incorrect) affirmative response while the executive system works harder to override this automatically initiated affirmative response to prepare the correct rejection response ('No, it's actually not a target').

Of course, people could try to artificially influence their response times by simply waiting longer to respond to any of the items which would diminish or even erase the response time difference. By forcing a response timeout, however, such 'faking' behavior can be prevented as was demonstrated by Kristina Suchotzki and colleagues in 2021.

The Millisecond RT-CIT task is based on the Suchotzki et al (2021) published procedure. It only focuses on the actual categorization task and does not run the mock crime.

Task Procedure

Participants learn about the categorization that will require them to categorize words as 'NEW' or 'OLD' (aka the targets) by pressing the response keys "A" or "L", respectively, as fast as possible. They then enter the Target Learning Phase that introduces the five targets (e.g. "Eiffel Tower"). Each learning trial presents the five target items for 30s and is followed by a recall screen with five textboxes. Participants are asked to enter all five targets in any order. By default, at least 3 learning trials are run. If participants recall all five items correctly after the last round, they move on to the test phase. Otherwise, additional learning trials are added.

Afterwards, participants work on the Categorization Task. The Categorization Task runs the five target items (OLD), the five probe items selected from the mock crime ('NEW'), and 20 control items ('NEW'). Each of these 30 stimuli is repeated 6 times. Each word is presented for 800ms or until the response is made. If no response is provided within this response window, the message 'To slow' is presented for 1000ms.

What it Measures

The Reaction Time Concealed Information Test (RT-CIT) is a response-time based tool to uncover an individual's 'guilty knowledge'

Psychological domains

• Processing Speed: Ability to quickly perceive a stimulus, process the information, and initiate a response
• Selective Attention: Ability to select information from sensory input by directing attention to a specific location
• Priming: Automatic cognitive memory process that facilitate item/concept recognition of previously encountered items
• Inhibitory Control / Response Inhibition: Ability to override automatic/dominant responses that interfere with one's goals

Main Performance Metrics

• RT-CIT Effect: Difference in average response times to primes and control items; main measure of RT-CIT effect

Psychiatric Conditions

The RT-CIT task is intended for academic research as well as for application in in forensic psychology, criminology, and legal investigations.

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Reaction Time Concealed Information Test (RT-CIT).

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Hu, Xiaoqing, & Rosenfeld, J. Peter. (2012). Combining the P300‐complex trial‐based Concealed Information Test and the reaction time‐based autobiographical Implicit Association Test in concealed memory detection. Psychophysiology, 49(8), 1090-1100.

Nooraven, E, & Verschuere, B. (2013). Predicting the sensitivity of the reaction time-based concealed information test. Applied Cognitive Psychology, 27(3), 328-335.

Hu, Xiaoqing, Evans, Angela, Wu, Haiyan, Lee, Kang, & Fu, Genyue. (2013). An interfering dot-probe task facilitates the detection of mock crime memory in a reaction time (RT)-based concealed information test. Acta Psychologica, 142(2), 278-285.

Suchotzki, Kristina, Kakavand, Aileen, & Gamer, Matthias. (2018). Validity of the Reaction Time Concealed Information Test in a Prison Sample. Frontiers in Psychiatry, 9, 745.

Norman, Danielle G, Gunnell, Daniel A, Mrowiec, Aleksandra J, & Watson, Derrick G. (2020). Seen this scene? Scene recognition in the reaction-time Concealed Information Test. Memory & Cognition, 48(8), 1388-1402.

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.