Multiplying out the average time for the tasks, they spent about 25 minutes total. If their goal was to recreate the conditions where people take these drugs in non-medical settings, they failed. It is not when you have a half hour of puzzles, and someone sitting next to you and scoring your work. It's when you have 24 hours of work and 16 hours to do it. Or, a 15 minute task that feels like pulling off your own fingernails.