Clock Test
System Requirements
Minimum: 1024×768
Recommended: 1280×800
May be challenging for colorblind participants
Description
PEBL Clock Test. An implementation of the Mackworth Clock Test. A sustained visual attention task--Watch for a clock to skip a beat.
About This Test
A sustained visual attention vigilance task. Participants watch a red target move around a circular clock face like a second hand, advancing one position every second. Occasionally (with probability pskip, default 40%), the clock 'skips a beat' by advancing two positions instead of one. Participants must press the spacebar when they detect a skip. The task measures vigilance and sustained attention by tracking hits (correct detections), false alarms (responses to normal ticks), and response times over an extended period (default 60 trials).
Test Details
clocktestclocktest.pbl🚀 Try Without Registration
Run this test immediately without creating an account. Data stays in your browser.
Researcher Access Required
To save configurations, upload data, use translations, track completion, and manage studies, please log in or register for an account.
Scientific Background
Original Task References:
These references describe the original task that this PEBL implementation is based on.
- Mackworth, N. H. (1948). Mackworth Clock Test. The Quarterly Journal of Experimental Psychology.
- Shackel, B. (1999). How I broke the Mackworth clock test (and what I learned). In Hanson, M., Lovesey, E. J., and Robertson, S. A. Contemporary Ergonomics 1999. Taylor & Francis. (pp. 193-197)
- Lichstein, K. L., Riedel, B. W., & Richman, S. L. (2000). The Mackworth clock test: A computerized version (statistical data included). The Journal of Psychology. http://www.encyclopedia.com/doc/1G1-62024427.html Gets x,y coordinates based on 1:60 minutes.
Data Output
Creates two data files: (1) clock-<subnum>.csv with trial-by-trial data containing columns: subnum (participant code), trial (trial number: 1 to number of trials), ticker (cumulative tick count incremented by 1 for normal tick or 2 for skip), sec (current position on clock face: 1-60), skip (whether clock skipped on this trial: 1=skip/target, 0=normal tick), resp (whether participant responded with spacebar: 1=responded, 0=no response), corr (response accuracy: 1=correct, 0=incorrect; correct means responding to skips and not responding to normal ticks), starttime (absolute response time in ms), rt (response time from trial start in ms), curtime (absolute time at trial end in ms); (2) clock-report-<subnum>.txt containing text summary with total trials, number of targets (skips), correct responses, correct target detections (hits), false alarms, and mean correct RT.
About This Test
PEBL Clock Test. An implementation of the Mackworth Clock Test. A sustained visual attention task--Watch for a clock to skip a beat.
Category: Visuospatial
Estimated Duration: 2 minutes
Available Translations: 1 language
Documentation Sources:
Test description file, Test implementation, PEBL wiki archive, Parameter schema
Documentation Status: Complete