Red Scientific

Products ISO 17488

Detection response task

A stimulus and response system for measuring the attentional effects of cognitive load with the method of ISO 17488:2016, in the laboratory, the simulator or on the road.

Detection response task timing Four stimuli arrive three to five seconds apart. Each opens a response window from 100 to 2500 milliseconds after onset. Three responses fall inside their windows and count as hits. One stimulus receives no response and counts as a miss. Stimulus Response Hit Hit Miss Hit 0246810121416 Time (s)
Fig. 1 Schematic of ISO 17488 timing. Stimuli arrive 3–5 s apart. A response between 100 and 2500 ms after onset, the shaded window, is a hit. The events shown are illustrative.
3
Stimulus types included
3–5s
Inter-stimulus interval
1ms
Reaction time resolution
2yr
Warranty

Method

While the participant drives and performs the task under study, a stimulus appears every three to five seconds. The participant presses the finger switch as soon as they detect it. ISO 17488 counts a press between 100 and 2500 ms after onset as a hit, and no press in that window as a miss. A stimulus answered in under 100 ms is excluded as premature.

Response time and hit rate are the two measures. As cognitive load rises, responses slow and more stimuli go undetected.

DRT response switch worn on the index finger of a hand on the steering wheel
Fig. 2 The response switch straps to a finger, so the participant can respond without moving a hand from the wheel.

Stimulus types

ISO 17488 describes three stimulus arrangements. The kit includes all of them.

Tactile DRT vibration motor taped near the collarbone

Tactile (TDRT)

A small vibration motor on the shoulder or collarbone. It places no demand on vision, which suits the evaluation of displays and touchscreens.

Head-mounted DRT LED on a headband

Head-mounted (HDRT)

A red LED on a light headband, in the peripheral visual field. It moves with the head, so its visual angle stays constant.

Remote DRT LED mounted on the dashboard

Remote (RDRT)

A fixed LED on the dashboard or A-pillar. Earlier literature calls this arrangement the peripheral detection task.

Specifications

Stimuli Vibration motor, head-mounted LED, remote LED
Inter-stimulus interval 3–5 s between stimulus onsets, randomized. Configurable
Stimulus duration 1000 ms or until the response, by default. Configurable
Reaction time Measured on the device, not the host computer. 1 ms resolution
Wired unit Reports each response about 5 ms late because of a fixed switch debounce. The offset is constant, so it cancels in comparisons between conditions
Wireless unit A hardware interrupt time-stamps the press. No debounce delay
Logged per stimulus Reaction time of the first press, or −1 when there is no press before the next stimulus. You apply the 100–2500 ms hit window of ISO 17488 in analysis
Control USB serial. RSLogger, or start and stop commands from your own software
Output CSV with one row per stimulus: onset time, reaction time and response count
Warranty Two years

Kit contents

  • One controller box
  • Two response buttons
  • Three stimuli: vibration motor, head-mounted LED and remote LED

Software

The DRT runs from RSLogger, which is included. Its DRT module sets the stimulus interval, duration and intensity, plots reaction times and misses during the session, and writes one row per stimulus to CSV. RSLogger stamps each row with the same host clock it uses for cameras, the eye tracker and the occlusion goggles recorded in the same session.

DRT module documentation

RSLogger DRT module showing stimulus state and reaction times
Fig. 3 RSLogger DRT module. The upper trace is stimulus state and the lower plot is reaction time per trial.

References

  1. ISO. (2016). ISO 17488:2016 Road vehicles — Transport information and control systems — Detection-response task (DRT) for assessing attentional effects of cognitive load in driving. International Organization for Standardization.
  2. NHTSA. (2014). Detection Response Task (DRT) Evaluation for Driver Distraction Measurement Application. DOT HS 812 077. National Highway Traffic Safety Administration.
  3. Cooper, J. M., Castro, S. C., & Strayer, D. L. (2016). Extending the detection response task to simultaneously measure cognitive and visual task demands. Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 60(1), 1962–1966.
  4. Engström, J., Markkula, G., Victor, T., & Merat, N. (2017). Effects of cognitive load on driving performance: The cognitive control hypothesis. Human Factors, 59(5), 734–764.

Ordering

Order the DRT kit

The complete kit carries a two-year warranty, and we ship worldwide. Tell us about your protocol and we will reply with a formal quote, usually within one business day.

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