When you consider that the researchers noticed more mind wandering with ingested doses of 15mg on subjects that do not use cannabis daily, the result is not all that surprising. That's a pretty healthy dose most people don't take BEFORE they go to work, unless they are a patient.
"Notably, those who received the smaller dose of 7.5 mg of THC did not differ significantly from the placebo group."
The moral of the story is, as always: Start LOW and go SLOW until you find the active ingredient combinations and amounts that are right for you.
Full Psypost.org article here.