Currently available for both all smart devices, DRUID is an application that has been designed to measure cognitive and behavior impairment following ingestion of drugs such as alcohol or marijuana. DRUID includes four Tasks to measure performance. The tasks are based on research on driving impairment and take about 5 minutes to complete. Assessing which psychomotor tasks are most effective in screening for driving impairment, calibrated with consumption of alcohol, Jongen et al. (2014) found the largest effect sizes with eyes-open balance, reaction time with divided attention, and the psychomotor vigilance task. Moskowitz (1985) found impaired hand-eye coordination (HEC) following marijuana consumption, and HEC has been used successfully to differentiate safe and unsafe older drivers (Bieri et al. 2014). Based on this research foundation, DRUID incorporates tasks that measure reaction time, decision making, Divided Attention Tasks (DATs), hand-eye coordination, and balance.
Here’s how it works
Reaction Time / Decision Making
Shapes flash on the screen for ½ second, either a square or a circle, one shape being the Target-shape and the other being the Control-shape. When the Target shape appears, the user is instructed to touch the screen where it appeared. If the Control-shape appears, the user is instructed to touch the oval button at the top of the screen. Users are thus required to do two things: make a decision about what type of shape appeared (square or circle) and take the required action (where to touch the screen). DRUID measures reaction time in touching the screen, and errors in choosing the correct action based on each stimulus shape and errors of distance where the user touches the screen.
DRUID produces measures of reaction time, errors in decision making, motor tracking, time estimation and balance, and an algorithm integrates these measures into an overall measure of impairment. When you do a TEST run, DRUID will tell you how your performance on the above measures compares with your baseline, e.g., “Your reaction time is 20% slower than BASELINE”, and DRUID also gives you your total impairment score, compared to your BASELINE, and gives you our current best estimate of your impairment score’s equivalent Blood Alcohol Concentration.
The Need For DRUID:
While there is as established level of blood alcohol associated with impaired driving, there is no comparable assessment for marijuana. THC levels in urine can persist long after marijuana intoxication has passed, and the National Highway Traffic Safety Administration states, “It is difficult to establish a relationship between a person’s THC blood or plasma concentration and performance impairing effects. Concentrations of parent drug and metabolite are very dependent on pattern of use as well as dose.” (NHTSA, 2016).
Benefits & Risks
“Start Your Day with DRUID”
Research has documented that playing video games enhances individuals’ reaction times without loss of accuracy (Ballesteros et al., 2014; Mack & Ilg, 2014; Toril, Reales & Ballesteros, 2014; Stroud & Whitbourne, 2015). The tasks in DRUID have elements of video games (hand-eye coordination, decision-making, concentration, operating with distractions). The development and validation of DRUID will likely provide a tool for improving general driving skills, particularly among aging adults (Ballesteros et al., 2014; Toril, Reales & Ballesteros, 2014).
As is the case for most neuro-psych assessment tools, there is minimal risk from the use of DRUID that participants would experience any discomfort or distress. The tasks in DRUID resemble video games, so if a participant gets disoriented from watching moving or flashing stimuli on a computer screen, they might experience some discomfort. If participants have a balance problem and have difficulty standing on one leg, they should not use DRUID without a way to catch themselves if they fall.
About The Creator
Michael Milburn has been a Professor of Psychology at the University of Massachusetts/Boston for almost 40 years. He received an AB in Psychology from Stanford University and a PhD from Harvard in Social Psychology, with a minor in Quantitative Methods.
He has published research in a variety of areas, including public opinion and political psychology, sexuality, the visual arts and quantitative methods. Prof. Milburn has been working with computers since his dad gave him his first FORTRAN programming book when he was in 8th grade.
Reaction Time / Time Estimation / DAT
Alteration in the perception of time passing is generally recognized as a characteristic of ingesting marijuana—Task 2 requires users to press a “Start” button to begin counting, and press a “Stop” button when they feel 60 seconds has passed. In addition, circles are flashed on the screen for ½ second, and the user is required to touch the screen where they appeared. Users are thus attempting to keep a time count going in their head as well as reacting to stimuli on the screen.
Motor Tracking / DAT
This task presents a circle that moves around the screen, sometimes jumping a distance, and the user is required to keep their finger on the circle as much as they can. In addition to keeping track of the moving circle, users are required to count the number of squares that flash on the screen for ½ second, thus incorporating a divided attention task.
Smart devices are able to measure movement in three dimensions, so DRUID incorporates testing of stability and balance, a key element of the Standard Field Sobriety Test (Downey et al., 2016). Users are instructed to stand on one leg for 30 seconds, holding the iPad in their opposite hand, trying to keep your device as still as possible. In Phase 1, users stand on their right leg; in Phase 2, on their left leg.