___________________________________________________________________________________________________________________ Mackworth Clock Vigilance Test ___________________________________________________________________________________________________________________ Script Author: Jeffrey Q. Ouyang (firstname.lastname@example.org) Date: 08-08-2011 last updated: 02-24-2022 by K. Borchert (email@example.com) for Millisecond Software, LLC Script Copyright © 02-24-2022 Millisecond Software ___________________________________________________________________________________________________________________ BACKGROUND INFO ___________________________________________________________________________________________________________________ This script implements the Mackworth Clock Vigilance TestT; a go/nogo test to measure a persons's ability to sustain attention in the face of monotonous stimulation. The implemented procedure is based on: -Ann M.W. et al. 2001. Developing measures of fatigue using an alcohol comparison to validate the effects of fatigue on performance. Accident Analysis and Prevention 33, 313-326. -Mats G. et al. 1994. Relations Between Perfromance and Subjective Ratings of Sleepiness During a Night Awake. Sleep 17, American Sleep Disorders Association and Sleep Research Society, 236-241. -Kenneth L.L. et al. 2000. The Macworth Clock Test: A Computerized Version, The Journal of Psychology, 134:2, 153-161 ___________________________________________________________________________________________________________________ TASK DESCRIPTION ___________________________________________________________________________________________________________________ Participants watch a red dot jump from one circle position to next position (24) in a clockwise fashion at constant speed. Occasionally, the red dot skips a position. Participants are asked to press the Spacebar whenever they notice such a skipped event (go event). ___________________________________________________________________________________________________________________ DURATION ___________________________________________________________________________________________________________________ the default set-up of the script takes appr. 1.5 minutes to complete ___________________________________________________________________________________________________________________ DATA FILE INFORMATION ___________________________________________________________________________________________________________________ The default data stored in the data files are: (1) Raw data file: 'mackworthclock_raw*.iqdat' (a separate file for each participant) build: The specific Inquisit version used (the 'build') that was run computer.platform: the platform the script was run on (win/mac/ios/android) date, time: date and time script was run subject, group, with the current subject/groupnumber session: with the current session id blockcode, blocknum: the name and number of the current block (built-in Inquisit variable) trialcode, trialnum: the name and number of the currently recorded trial (built-in Inquisit variable) Note: trialnum is a built-in Inquisit variable; it counts all trials run; even those that do not store data to the data file such as feedback trials. Thus, trialnum may not reflect the number of main trials run per block. responseWindow: 1 = the response Window is active AT THE BEGINNING of the trial 0 = the response Window is inactive AT THE BEGINNING of the trial hit: 1 = hit (spacebar pressed after skipped event within allowed timeframe); 0 = no hit miss: 1 = miss (spacebar not pressed after skipped event within allowed timeframe); 0 = no miss false_alarm: 1 = False Alarm (spacebar pressed after a non-skipped event); 0 = no FA total_hits: counts all hits during test total_misses: counts all misses during test total_falsealarms: counts all false alarms during test skip_count: counts the number of skipped events during test (2) Summary data file: 'mackworthclock_summary*.iqdat' (a separate file for each participant) inquisit.version: Inquisit version run computer.platform: the platform the script was run on (win/mac/ios/android) startdate: date script was run starttime: time script was started subjectid: assigned subject id number groupid: assigned group id number sessionid: assigned session id number elapsedtime: time it took to run script (in ms); measured from onset to offset of script completed: 0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run) total_hits: counts all hits during test total_misses: counts all misses during test total_falsealarms: counts all false alarms during test skip_count: counts the number of skipped events during test response_window_duration: parameter: the max time in ms that a participant can respond after a signal (skip) event Mean_HitRT: stores the mean Hit latency (in ms) across test blocks STD_HitRT: stores the standard deviation of all Hit latencies (in ms) across test blocks Median_HitRT: stores the median Hit latency (in ms) across test blocks _______________________________________________________________________________________________________________ EXPERIMENTAL SET-UP ___________________________________________________________________________________________________________________ Test Procedures: 1. A circle, with 24 equally spaced "slots" (as represented by the empty space between two "+" marks), is presented on the computer screen. 2. A red dot starts from the 12'o clock position and flashes in turn in each "slot". 2a.The dot stays visible for 0.65 sec and so there is an interval of 0.65 sec between each flash. 3. The signal event is when the dot skips a position. 3a.Total number of signal events is user-definable. 3b.The signal events are "spread out" evenly around the average event intervals with pseudorandom components added in (rand(-10,10)). 3c.The subject identifies this event by hitting the space bar (or other user-definable key). 4. The entire test lasts up to a pre-defined amount of time. Note: the current script is programmed in such a way that the sequence (pretest->maintest) can be run multiple times if more than one round should be run. Go to section EXPERIMENT and update the block section of the expt-element if you wish to run multiple rounds. ___________________________________________________________________________________________________________________ INSTRUCTIONS ___________________________________________________________________________________________________________________ check under section Editable Instructions ___________________________________________________________________________________________________________________ EDITABLE CODE ___________________________________________________________________________________________________________________ check below for (relatively) easily editable parameters, stimuli, instructions etc. Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment. The parameters you can change are: User-definable Macworth clock test parameters: total_skip_events: Total number of signal (skip) events. total_runtime: Total amount of time in ms the Macworth clock test will run. norm_interval: Interval between regular dot "flashes". (in ms, recommended: 500ms - 800ms, default: 650ms) skip_interval: Flash Interval when there's a skip event. (in ms, recommended: 500ms - 800ms, default: 650ms) response_window_duration: the max time in ms that a participant can respond after a signal (skip) event *Note: If possible, skip events will be randomly distributed such that the duration before the next event is at least as long as the specified response window. This may not be possible, however, if relative large number of events are specified for a relative short task time, or if the response window is too long.