Deary-Liewald Reaction Time Task (DL)

Background

The Deary-Liewald Reaction Time Tasks are simple measures of processing and decision-making speed to visual stimuli. The battery contains two tasks:

1. The Deary-Liewald Simple Reaction Time Task (DLS): This task estimates pure processing speed by measuring keyboard responses to a simple 'X' stimulus that appears in a white box at the center of the screen at random intervals.
2. The Deary-Liewald Choice Reaction Time Task (DLC): This task adds another level of complexity to the response decision by providing four different screen locations that the target X can appear in, all linked to a different response key. This task measures decision-making beyond simple stimulus processing time.

Ian Deary and David Liewald, together with Jack Nissan, published the design of this response time battery in 2011 to provide standard, streamlined, publicly accessible and easy to use response time measures to make comparisons across studies more meaningful as well as to provide simple, standard measures for predictor or outcome variables. The authors also provided means and response variability measures across several age groups. However, they caution against using them as actual 'norms' as they envision slight between-study differences in overall levels of reaction times, based on hardware differences.

Task Procedure

Both reaction time tasks use a streamlined user interface. In both tasks, the target stimulus is the letter 'X' which can appear in a white box that is visible on the screen throughout the task. Both Millisecond implementations run an (optional) external keyboard check at the beginning of the script to ensure that all participants work on external keyboards. Both tests collect age information to calculate 'norms' based on the published data by Deary et al (2011) as simple comparison variables for interested researchers.

The Deary-Liewald Simple Reaction Time Task (DLS)

By default settings, the DLS runs 8 practice trials before running 1 test block of 20 trials. Each trial presents a white box in the center of the screen. The target 'X' appears with randomly selected delays between 1000-3000ms. The target stays on screen until participants press key 'B'. Early responses as well slow responses (> 5000ms) are ignored but tracked and not counted towards summary statistics.

The Deary-Liewald Choice Reaction Time Task (DLC)

By default settings, the DLC runs 8 practice trials with error feedback before running 1 test block of 40 trials. Each trial presents four white boxes located on the horizontal center line of the screen. The target 'X' appears with randomly selected delays between 1000-3000ms in a randomly selected box. The target stays on screen until participants press the corresponding response key ("CVNM", located in a line from left to right on QWERTY keyboards). Early responses as well slow responses (> 5000ms) are ignored but tracked and not counted towards summary statistics. Response times to correct and incorrect responses are tracked separately.

What it Measures

The Deary-Liewald Reaction Time Tasks are measures of processing and decision-making speed to visual stimuli

Psychological domains

• Processing Speed: Ability to quickly perceive a stimulus, process the information, and initiate a response
• Decision Making: Choosing the correct response from multiple alternatives.
• Selective Attention: Ability to discriminate between different stimuli locations and select the correct response key
• Sustained Attention: Ability to maintain focus and quickly adapt one's behavior to current demands

Main Performance Metrics

• Response Times: correct response times (in ms) to stimulus presentation; measures of processing speed/decision making speed
• Response Times Variability: response time variability of correct responses

Psychiatric Conditions

The DLS/DLC response time battery has been used to assess the following clinical populations:

• Alzheimer’s Disease & Dementia
• Schizophrenia
• Stroke
• Brain Tumor patients

Test Variations

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Deary-Liewald Reaction Time Task (DL).

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Deary, I. J., Liewald, D., & Nissan, J. (2011). A free, easy-to-use, computer-based simple and four-choice reaction time programme: The Deary-Liewald reaction time task. Behavior Research Methods, 43(1), 258–268. https://doi.org/10.3758/s13428-010-0024-1

Dua, S., Singh, P., & Saha, S. (2020). A Study to Assess and Correlate Serum Lipid Profile with Reaction Time in Healthy Individuals. Indian Journal of Clinical Biochemistry, 35(4), 482–487. https://doi.org/10.1007/s12291-019-00850-z

Ferreira, S., Raimundo, A., del Pozo-Cruz, J., & Marmeleira, J. (2021). Psychometric properties of a computerized and hand-reaction time tests in older adults using long-term facilities with and without mild cognitive impairment. Experimental Gerontology, 147, Article 111271. https://doi.org/10.1016/j.exger.2021.111271

JOSHI, S., & PRANITA GANJAVE, D. (2024). Comparative Study Of Simple And Choice Visual Reaction Time In Elite And Novice Table Tennis Players. International Journal of Research and Analytical Reviews, 11(3). https://doi.org/10.56975/ijrar.v11i3.296308